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/*
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 *
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 * Copyright (C) 2003 the ffmpeg project
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 *
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 * This library is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2 of the License, or (at your option) any later version.
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 *
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 * This library is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with this library; if not, write to the Free Software
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 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
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 *
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 * VP3 Video Decoder by Mike Melanson (melanson@pcisys.net)
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 * For more information about the VP3 coding process, visit:
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 *   http://www.pcisys.net/~melanson/codecs/
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 *
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 */
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/**
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 * @file vp3.c
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 * On2 VP3 Video Decoder
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 */
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <unistd.h>
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#include "common.h"
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#include "avcodec.h"
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#include "dsputil.h"
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#include "mpegvideo.h"
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#include "dsputil.h"
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#include "vp3data.h"
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#define FRAGMENT_PIXELS 8
44

    
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/* 
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 * Debugging Variables
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 * 
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 * Define one or more of the following compile-time variables to 1 to obtain
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 * elaborate information about certain aspects of the decoding process.
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 *
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 * KEYFRAMES_ONLY: set this to 1 to only see keyframes (VP3 slideshow mode)
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 * DEBUG_VP3: high-level decoding flow
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 * DEBUG_INIT: initialization parameters
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 * DEBUG_DEQUANTIZERS: display how the dequanization tables are built
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 * DEBUG_BLOCK_CODING: unpacking the superblock/macroblock/fragment coding
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 * DEBUG_MODES: unpacking the coding modes for individual fragments
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 * DEBUG_VECTORS: display the motion vectors
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 * DEBUG_TOKEN: display exhaustive information about each DCT token
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 * DEBUG_VLC: display the VLCs as they are extracted from the stream
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 * DEBUG_DC_PRED: display the process of reversing DC prediction
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 * DEBUG_IDCT: show every detail of the IDCT process
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 */
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#define KEYFRAMES_ONLY 0
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#define DEBUG_VP3 0
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#define DEBUG_INIT 0
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#define DEBUG_DEQUANTIZERS 0
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#define DEBUG_BLOCK_CODING 0
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#define DEBUG_MODES 0
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#define DEBUG_VECTORS 0
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#define DEBUG_TOKEN 0
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#define DEBUG_VLC 0
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#define DEBUG_DC_PRED 0
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#define DEBUG_IDCT 0
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#if DEBUG_VP3
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#define debug_vp3 printf
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#else
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static inline void debug_vp3(const char *format, ...) { }
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#endif
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#if DEBUG_INIT
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#define debug_init printf
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#else
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static inline void debug_init(const char *format, ...) { }
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#endif
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#if DEBUG_DEQUANTIZERS
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#define debug_dequantizers printf 
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#else
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static inline void debug_dequantizers(const char *format, ...) { } 
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#endif
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#if DEBUG_BLOCK_CODING
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#define debug_block_coding printf 
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#else
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static inline void debug_block_coding(const char *format, ...) { } 
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#endif
100

    
101
#if DEBUG_MODES
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#define debug_modes printf 
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#else
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static inline void debug_modes(const char *format, ...) { } 
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#endif
106

    
107
#if DEBUG_VECTORS
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#define debug_vectors printf 
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#else
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static inline void debug_vectors(const char *format, ...) { } 
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#endif
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#if DEBUG_TOKEN 
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#define debug_token printf 
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#else
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static inline void debug_token(const char *format, ...) { } 
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#endif
118

    
119
#if DEBUG_VLC
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#define debug_vlc printf 
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#else
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static inline void debug_vlc(const char *format, ...) { } 
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#endif
124

    
125
#if DEBUG_DC_PRED
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#define debug_dc_pred printf 
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#else
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static inline void debug_dc_pred(const char *format, ...) { } 
129
#endif
130

    
131
#if DEBUG_IDCT
132
#define debug_idct printf 
133
#else
134
static inline void debug_idct(const char *format, ...) { } 
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#endif
136

    
137
typedef struct Vp3Fragment {
138
    DCTELEM coeffs[64];
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    int coding_method;
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    int coeff_count;
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    int last_coeff;
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    int motion_x;
143
    int motion_y;
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    /* address of first pixel taking into account which plane the fragment
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     * lives on as well as the plane stride */
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    int first_pixel;
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    /* this is the macroblock that the fragment belongs to */
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    int macroblock;
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} Vp3Fragment;
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#define SB_NOT_CODED        0
152
#define SB_PARTIALLY_CODED  1
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#define SB_FULLY_CODED      2
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#define MODE_INTER_NO_MV      0
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#define MODE_INTRA            1
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#define MODE_INTER_PLUS_MV    2
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#define MODE_INTER_LAST_MV    3
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#define MODE_INTER_PRIOR_LAST 4
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#define MODE_USING_GOLDEN     5
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#define MODE_GOLDEN_MV        6
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#define MODE_INTER_FOURMV     7
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#define CODING_MODE_COUNT     8
164

    
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/* special internal mode */
166
#define MODE_COPY             8
167

    
168
/* There are 6 preset schemes, plus a free-form scheme */
169
static int ModeAlphabet[7][CODING_MODE_COUNT] =
170
{
171
    /* this is the custom scheme */
172
    { 0, 0, 0, 0, 0, 0, 0, 0 },
173

    
174
    /* scheme 1: Last motion vector dominates */
175
    {    MODE_INTER_LAST_MV,    MODE_INTER_PRIOR_LAST,  
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         MODE_INTER_PLUS_MV,    MODE_INTER_NO_MV,
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         MODE_INTRA,            MODE_USING_GOLDEN,      
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         MODE_GOLDEN_MV,        MODE_INTER_FOURMV },
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180
    /* scheme 2 */
181
    {    MODE_INTER_LAST_MV,    MODE_INTER_PRIOR_LAST,  
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         MODE_INTER_NO_MV,      MODE_INTER_PLUS_MV,
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         MODE_INTRA,            MODE_USING_GOLDEN,      
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         MODE_GOLDEN_MV,        MODE_INTER_FOURMV },
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186
    /* scheme 3 */
187
    {    MODE_INTER_LAST_MV,    MODE_INTER_PLUS_MV,     
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         MODE_INTER_PRIOR_LAST, MODE_INTER_NO_MV,
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         MODE_INTRA,            MODE_USING_GOLDEN,      
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         MODE_GOLDEN_MV,        MODE_INTER_FOURMV },
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    /* scheme 4 */
193
    {    MODE_INTER_LAST_MV,    MODE_INTER_PLUS_MV,     
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         MODE_INTER_NO_MV,      MODE_INTER_PRIOR_LAST,
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         MODE_INTRA,            MODE_USING_GOLDEN,      
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         MODE_GOLDEN_MV,        MODE_INTER_FOURMV },
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    /* scheme 5: No motion vector dominates */
199
    {    MODE_INTER_NO_MV,      MODE_INTER_LAST_MV,     
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         MODE_INTER_PRIOR_LAST, MODE_INTER_PLUS_MV,
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         MODE_INTRA,            MODE_USING_GOLDEN,      
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         MODE_GOLDEN_MV,        MODE_INTER_FOURMV },
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    /* scheme 6 */
205
    {    MODE_INTER_NO_MV,      MODE_USING_GOLDEN,      
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         MODE_INTER_LAST_MV,    MODE_INTER_PRIOR_LAST,
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         MODE_INTER_PLUS_MV,    MODE_INTRA,             
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         MODE_GOLDEN_MV,        MODE_INTER_FOURMV },
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};
211

    
212
#define MIN_DEQUANT_VAL 2
213

    
214
typedef struct Vp3DecodeContext {
215
    AVCodecContext *avctx;
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    int width, height;
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    AVFrame golden_frame;
218
    AVFrame last_frame;
219
    AVFrame current_frame;
220
    int keyframe;
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    DSPContext dsp;
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223
    int quality_index;
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    int last_quality_index;
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    int superblock_count;
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    int superblock_width;
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    int superblock_height;
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    int y_superblock_width;
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    int y_superblock_height;
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    int c_superblock_width;
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    int c_superblock_height;
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    int u_superblock_start;
234
    int v_superblock_start;
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    unsigned char *superblock_coding;
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    int macroblock_count;
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    int macroblock_width;
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    int macroblock_height;
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    int fragment_count;
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    int fragment_width;
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    int fragment_height;
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    Vp3Fragment *all_fragments;
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    int u_fragment_start;
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    int v_fragment_start;
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    /* this is a list of indices into the all_fragments array indicating
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     * which of the fragments are coded */
251
    int *coded_fragment_list;
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    int coded_fragment_list_index;
253
    int pixel_addresses_inited;
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    VLC dc_vlc[16];
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    VLC ac_vlc_1[16];
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    VLC ac_vlc_2[16];
258
    VLC ac_vlc_3[16];
259
    VLC ac_vlc_4[16];
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    int16_t intra_y_dequant[64];
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    int16_t intra_c_dequant[64];
263
    int16_t inter_dequant[64];
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265
    /* This table contains superblock_count * 16 entries. Each set of 16
266
     * numbers corresponds to the fragment indices 0..15 of the superblock.
267
     * An entry will be -1 to indicate that no entry corresponds to that
268
     * index. */
269
    int *superblock_fragments;
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271
    /* This table contains superblock_count * 4 entries. Each set of 4
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     * numbers corresponds to the macroblock indices 0..3 of the superblock.
273
     * An entry will be -1 to indicate that no entry corresponds to that
274
     * index. */
275
    int *superblock_macroblocks;
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277
    /* This table contains macroblock_count * 6 entries. Each set of 6
278
     * numbers corresponds to the fragment indices 0..5 which comprise
279
     * the macroblock (4 Y fragments and 2 C fragments). */
280
    int *macroblock_fragments;
281
    /* This is an array that indicates how a particular macroblock 
282
     * is coded. */
283
    unsigned char *macroblock_coding;
284

    
285
    int first_coded_y_fragment;
286
    int first_coded_c_fragment;
287
    int last_coded_y_fragment;
288
    int last_coded_c_fragment;
289

    
290
    uint8_t edge_emu_buffer[9*2048]; //FIXME dynamic alloc
291
    uint8_t qscale_table[2048]; //FIXME dynamic alloc (width+15)/16
292
} Vp3DecodeContext;
293

    
294
/************************************************************************
295
 * VP3 I/DCT
296
 ************************************************************************/
297

    
298
#define IdctAdjustBeforeShift 8
299
#define xC1S7 64277
300
#define xC2S6 60547
301
#define xC3S5 54491
302
#define xC4S4 46341
303
#define xC5S3 36410
304
#define xC6S2 25080
305
#define xC7S1 12785
306

    
307
void vp3_idct_c(int16_t *input_data, int16_t *dequant_matrix, 
308
    int16_t *output_data)
309
{
310
    int32_t intermediate_data[64];
311
    int32_t *ip = intermediate_data;
312
    int16_t *op = output_data;
313

    
314
    int32_t A_, B_, C_, D_, _Ad, _Bd, _Cd, _Dd, E_, F_, G_, H_;
315
    int32_t _Ed, _Gd, _Add, _Bdd, _Fd, _Hd;
316
    int32_t t1, t2;
317

    
318
    int i, j;
319

    
320
    debug_idct("raw coefficient block:\n");
321
    for (i = 0; i < 8; i++) {
322
        for (j = 0; j < 8; j++) {
323
            debug_idct(" %5d", input_data[i * 8 + j]);
324
        }
325
        debug_idct("\n");
326
    }
327
    debug_idct("\n");
328

    
329
    for (i = 0; i < 64; i++) {
330
        j = dezigzag_index[i];
331
        intermediate_data[j] = dequant_matrix[i] * input_data[i];
332
    }
333

    
334
    debug_idct("dequantized block:\n");
335
    for (i = 0; i < 8; i++) {
336
        for (j = 0; j < 8; j++) {
337
            debug_idct(" %5d", intermediate_data[i * 8 + j]);
338
        }
339
        debug_idct("\n");
340
    }
341
    debug_idct("\n");
342

    
343
    /* Inverse DCT on the rows now */
344
    for (i = 0; i < 8; i++) {
345
        /* Check for non-zero values */
346
        if ( ip[0] | ip[1] | ip[2] | ip[3] | ip[4] | ip[5] | ip[6] | ip[7] ) {
347
            t1 = (int32_t)(xC1S7 * ip[1]);
348
            t2 = (int32_t)(xC7S1 * ip[7]);
349
            t1 >>= 16;
350
            t2 >>= 16;
351
            A_ = t1 + t2;
352

    
353
            t1 = (int32_t)(xC7S1 * ip[1]);
354
            t2 = (int32_t)(xC1S7 * ip[7]);
355
            t1 >>= 16;
356
            t2 >>= 16;
357
            B_ = t1 - t2;
358

    
359
            t1 = (int32_t)(xC3S5 * ip[3]);
360
            t2 = (int32_t)(xC5S3 * ip[5]);
361
            t1 >>= 16;
362
            t2 >>= 16;
363
            C_ = t1 + t2;
364

    
365
            t1 = (int32_t)(xC3S5 * ip[5]);
366
            t2 = (int32_t)(xC5S3 * ip[3]);
367
            t1 >>= 16;
368
            t2 >>= 16;
369
            D_ = t1 - t2;
370

    
371

    
372
            t1 = (int32_t)(xC4S4 * (A_ - C_));
373
            t1 >>= 16;
374
            _Ad = t1;
375

    
376
            t1 = (int32_t)(xC4S4 * (B_ - D_));
377
            t1 >>= 16;
378
            _Bd = t1;
379

    
380

    
381
            _Cd = A_ + C_;
382
            _Dd = B_ + D_;
383

    
384
            t1 = (int32_t)(xC4S4 * (ip[0] + ip[4]));
385
            t1 >>= 16;
386
            E_ = t1;
387

    
388
            t1 = (int32_t)(xC4S4 * (ip[0] - ip[4]));
389
            t1 >>= 16;
390
            F_ = t1;
391

    
392
            t1 = (int32_t)(xC2S6 * ip[2]);
393
            t2 = (int32_t)(xC6S2 * ip[6]);
394
            t1 >>= 16;
395
            t2 >>= 16;
396
            G_ = t1 + t2;
397

    
398
            t1 = (int32_t)(xC6S2 * ip[2]);
399
            t2 = (int32_t)(xC2S6 * ip[6]);
400
            t1 >>= 16;
401
            t2 >>= 16;
402
            H_ = t1 - t2;
403

    
404

    
405
            _Ed = E_ - G_;
406
            _Gd = E_ + G_;
407

    
408
            _Add = F_ + _Ad;
409
            _Bdd = _Bd - H_;
410

    
411
            _Fd = F_ - _Ad;
412
            _Hd = _Bd + H_;
413

    
414
            /*  Final sequence of operations over-write original inputs. */
415
            ip[0] = (int16_t)((_Gd + _Cd )   >> 0);
416
            ip[7] = (int16_t)((_Gd - _Cd )   >> 0);
417

    
418
            ip[1] = (int16_t)((_Add + _Hd )  >> 0);
419
            ip[2] = (int16_t)((_Add - _Hd )  >> 0);
420

    
421
            ip[3] = (int16_t)((_Ed + _Dd )   >> 0);
422
            ip[4] = (int16_t)((_Ed - _Dd )   >> 0);
423

    
424
            ip[5] = (int16_t)((_Fd + _Bdd )  >> 0);
425
            ip[6] = (int16_t)((_Fd - _Bdd )  >> 0);
426

    
427
        }
428

    
429
        ip += 8;            /* next row */
430
    }
431

    
432
    ip = intermediate_data;
433

    
434
    for ( i = 0; i < 8; i++) {
435
        /* Check for non-zero values (bitwise or faster than ||) */
436
        if ( ip[0 * 8] | ip[1 * 8] | ip[2 * 8] | ip[3 * 8] |
437
             ip[4 * 8] | ip[5 * 8] | ip[6 * 8] | ip[7 * 8] ) {
438

    
439
            t1 = (int32_t)(xC1S7 * ip[1*8]);
440
            t2 = (int32_t)(xC7S1 * ip[7*8]);
441
            t1 >>= 16;
442
            t2 >>= 16;
443
            A_ = t1 + t2;
444

    
445
            t1 = (int32_t)(xC7S1 * ip[1*8]);
446
            t2 = (int32_t)(xC1S7 * ip[7*8]);
447
            t1 >>= 16;
448
            t2 >>= 16;
449
            B_ = t1 - t2;
450

    
451
            t1 = (int32_t)(xC3S5 * ip[3*8]);
452
            t2 = (int32_t)(xC5S3 * ip[5*8]);
453
            t1 >>= 16;
454
            t2 >>= 16;
455
            C_ = t1 + t2;
456

    
457
            t1 = (int32_t)(xC3S5 * ip[5*8]);
458
            t2 = (int32_t)(xC5S3 * ip[3*8]);
459
            t1 >>= 16;
460
            t2 >>= 16;
461
            D_ = t1 - t2;
462

    
463

    
464
            t1 = (int32_t)(xC4S4 * (A_ - C_));
465
            t1 >>= 16;
466
            _Ad = t1;
467

    
468
            t1 = (int32_t)(xC4S4 * (B_ - D_));
469
            t1 >>= 16;
470
            _Bd = t1;
471

    
472

    
473
            _Cd = A_ + C_;
474
            _Dd = B_ + D_;
475

    
476
            t1 = (int32_t)(xC4S4 * (ip[0*8] + ip[4*8]));
477
            t1 >>= 16;
478
            E_ = t1;
479

    
480
            t1 = (int32_t)(xC4S4 * (ip[0*8] - ip[4*8]));
481
            t1 >>= 16;
482
            F_ = t1;
483

    
484
            t1 = (int32_t)(xC2S6 * ip[2*8]);
485
            t2 = (int32_t)(xC6S2 * ip[6*8]);
486
            t1 >>= 16;
487
            t2 >>= 16;
488
            G_ = t1 + t2;
489

    
490
            t1 = (int32_t)(xC6S2 * ip[2*8]);
491
            t2 = (int32_t)(xC2S6 * ip[6*8]);
492
            t1 >>= 16;
493
            t2 >>= 16;
494
            H_ = t1 - t2;
495

    
496

    
497
            _Ed = E_ - G_;
498
            _Gd = E_ + G_;
499

    
500
            _Add = F_ + _Ad;
501
            _Bdd = _Bd - H_;
502

    
503
            _Fd = F_ - _Ad;
504
            _Hd = _Bd + H_;
505

    
506
            _Gd += IdctAdjustBeforeShift;
507
            _Add += IdctAdjustBeforeShift;
508
            _Ed += IdctAdjustBeforeShift;
509
            _Fd += IdctAdjustBeforeShift;
510

    
511
            /* Final sequence of operations over-write original inputs. */
512
            op[0*8] = (int16_t)((_Gd + _Cd )   >> 4);
513
            op[7*8] = (int16_t)((_Gd - _Cd )   >> 4);
514

    
515
            op[1*8] = (int16_t)((_Add + _Hd )  >> 4);
516
            op[2*8] = (int16_t)((_Add - _Hd )  >> 4);
517

    
518
            op[3*8] = (int16_t)((_Ed + _Dd )   >> 4);
519
            op[4*8] = (int16_t)((_Ed - _Dd )   >> 4);
520

    
521
            op[5*8] = (int16_t)((_Fd + _Bdd )  >> 4);
522
            op[6*8] = (int16_t)((_Fd - _Bdd )  >> 4);
523

    
524
        } else {
525

    
526
            op[0*8] = 0;
527
            op[7*8] = 0;
528
            op[1*8] = 0;
529
            op[2*8] = 0;
530
            op[3*8] = 0;
531
            op[4*8] = 0;
532
            op[5*8] = 0;
533
            op[6*8] = 0;
534
        }
535

    
536
        ip++;            /* next column */
537
        op++;
538
    }
539
}
540

    
541
void vp3_idct_put(int16_t *input_data, int16_t *dequant_matrix, 
542
    uint8_t *dest, int stride)
543
{
544
    int16_t transformed_data[64];
545
    int16_t *op;
546
    int i, j;
547

    
548
    vp3_idct_c(input_data, dequant_matrix, transformed_data);
549

    
550
    /* place in final output */
551
    op = transformed_data;
552
    for (i = 0; i < 8; i++) {
553
        for (j = 0; j < 8; j++) {
554
            if (*op < -128)
555
                *dest = 0;
556
            else if (*op > 127)
557
                *dest = 255;
558
            else
559
                *dest = (uint8_t)(*op + 128);
560
            op++;
561
            dest++;
562
        }
563
        dest += (stride - 8);
564
    }
565
}
566

    
567
void vp3_idct_add(int16_t *input_data, int16_t *dequant_matrix, 
568
    uint8_t *dest, int stride)
569
{
570
    int16_t transformed_data[64];
571
    int16_t *op;
572
    int i, j;
573
    int16_t sample;
574

    
575
    vp3_idct_c(input_data, dequant_matrix, transformed_data);
576

    
577
    /* place in final output */
578
    op = transformed_data;
579
    for (i = 0; i < 8; i++) {
580
        for (j = 0; j < 8; j++) {
581
            sample = *dest + *op;
582
            if (sample < 0)
583
                *dest = 0;
584
            else if (sample > 255)
585
                *dest = 255;
586
            else
587
                *dest = (uint8_t)(sample & 0xFF);
588
            op++;
589
            dest++;
590
        }
591
        dest += (stride - 8);
592
    }
593
}
594

    
595
/************************************************************************
596
 * VP3 specific functions
597
 ************************************************************************/
598

    
599
/*
600
 * This function sets up all of the various blocks mappings:
601
 * superblocks <-> fragments, macroblocks <-> fragments,
602
 * superblocks <-> macroblocks
603
 *
604
 * Returns 0 is successful; returns 1 if *anything* went wrong.
605
 */
606
static int init_block_mapping(Vp3DecodeContext *s) 
607
{
608
    int i, j;
609
    signed int hilbert_walk_y[16];
610
    signed int hilbert_walk_c[16];
611
    signed int hilbert_walk_mb[4];
612

    
613
    int current_fragment = 0;
614
    int current_width = 0;
615
    int current_height = 0;
616
    int right_edge = 0;
617
    int bottom_edge = 0;
618
    int superblock_row_inc = 0;
619
    int *hilbert = NULL;
620
    int mapping_index = 0;
621

    
622
    int current_macroblock;
623
    int c_fragment;
624

    
625
    signed char travel_width[16] = {
626
         1,  1,  0, -1, 
627
         0,  0,  1,  0,
628
         1,  0,  1,  0,
629
         0, -1,  0,  1
630
    };
631

    
632
    signed char travel_height[16] = {
633
         0,  0,  1,  0,
634
         1,  1,  0, -1,
635
         0,  1,  0, -1,
636
        -1,  0, -1,  0
637
    };
638

    
639
    signed char travel_width_mb[4] = {
640
         1,  0,  1,  0
641
    };
642

    
643
    signed char travel_height_mb[4] = {
644
         0,  1,  0, -1
645
    };
646

    
647
    debug_vp3("  vp3: initialize block mapping tables\n");
648

    
649
    /* figure out hilbert pattern per these frame dimensions */
650
    hilbert_walk_y[0]  = 1;
651
    hilbert_walk_y[1]  = 1;
652
    hilbert_walk_y[2]  = s->fragment_width;
653
    hilbert_walk_y[3]  = -1;
654
    hilbert_walk_y[4]  = s->fragment_width;
655
    hilbert_walk_y[5]  = s->fragment_width;
656
    hilbert_walk_y[6]  = 1;
657
    hilbert_walk_y[7]  = -s->fragment_width;
658
    hilbert_walk_y[8]  = 1;
659
    hilbert_walk_y[9]  = s->fragment_width;
660
    hilbert_walk_y[10]  = 1;
661
    hilbert_walk_y[11] = -s->fragment_width;
662
    hilbert_walk_y[12] = -s->fragment_width;
663
    hilbert_walk_y[13] = -1;
664
    hilbert_walk_y[14] = -s->fragment_width;
665
    hilbert_walk_y[15] = 1;
666

    
667
    hilbert_walk_c[0]  = 1;
668
    hilbert_walk_c[1]  = 1;
669
    hilbert_walk_c[2]  = s->fragment_width / 2;
670
    hilbert_walk_c[3]  = -1;
671
    hilbert_walk_c[4]  = s->fragment_width / 2;
672
    hilbert_walk_c[5]  = s->fragment_width / 2;
673
    hilbert_walk_c[6]  = 1;
674
    hilbert_walk_c[7]  = -s->fragment_width / 2;
675
    hilbert_walk_c[8]  = 1;
676
    hilbert_walk_c[9]  = s->fragment_width / 2;
677
    hilbert_walk_c[10]  = 1;
678
    hilbert_walk_c[11] = -s->fragment_width / 2;
679
    hilbert_walk_c[12] = -s->fragment_width / 2;
680
    hilbert_walk_c[13] = -1;
681
    hilbert_walk_c[14] = -s->fragment_width / 2;
682
    hilbert_walk_c[15] = 1;
683

    
684
    hilbert_walk_mb[0] = 1;
685
    hilbert_walk_mb[1] = s->macroblock_width;
686
    hilbert_walk_mb[2] = 1;
687
    hilbert_walk_mb[3] = -s->macroblock_width;
688

    
689
    /* iterate through each superblock (all planes) and map the fragments */
690
    for (i = 0; i < s->superblock_count; i++) {
691
        debug_init("    superblock %d (u starts @ %d, v starts @ %d)\n",
692
            i, s->u_superblock_start, s->v_superblock_start);
693

    
694
        /* time to re-assign the limits? */
695
        if (i == 0) {
696

    
697
            /* start of Y superblocks */
698
            right_edge = s->fragment_width;
699
            bottom_edge = s->fragment_height;
700
            current_width = -1;
701
            current_height = 0;
702
            superblock_row_inc = 3 * s->fragment_width - 
703
                (s->y_superblock_width * 4 - s->fragment_width);
704
            hilbert = hilbert_walk_y;
705

    
706
            /* the first operation for this variable is to advance by 1 */
707
            current_fragment = -1;
708

    
709
        } else if (i == s->u_superblock_start) {
710

    
711
            /* start of U superblocks */
712
            right_edge = s->fragment_width / 2;
713
            bottom_edge = s->fragment_height / 2;
714
            current_width = -1;
715
            current_height = 0;
716
            superblock_row_inc = 3 * (s->fragment_width / 2) - 
717
                (s->c_superblock_width * 4 - s->fragment_width / 2);
718
            hilbert = hilbert_walk_c;
719

    
720
            /* the first operation for this variable is to advance by 1 */
721
            current_fragment = s->u_fragment_start - 1;
722

    
723
        } else if (i == s->v_superblock_start) {
724

    
725
            /* start of V superblocks */
726
            right_edge = s->fragment_width / 2;
727
            bottom_edge = s->fragment_height / 2;
728
            current_width = -1;
729
            current_height = 0;
730
            superblock_row_inc = 3 * (s->fragment_width / 2) - 
731
                (s->c_superblock_width * 4 - s->fragment_width / 2);
732
            hilbert = hilbert_walk_c;
733

    
734
            /* the first operation for this variable is to advance by 1 */
735
            current_fragment = s->v_fragment_start - 1;
736

    
737
        }
738

    
739
        if (current_width >= right_edge - 1) {
740
            /* reset width and move to next superblock row */
741
            current_width = -1;
742
            current_height += 4;
743

    
744
            /* fragment is now at the start of a new superblock row */
745
            current_fragment += superblock_row_inc;
746
        }
747

    
748
        /* iterate through all 16 fragments in a superblock */
749
        for (j = 0; j < 16; j++) {
750
            current_fragment += hilbert[j];
751
            current_width += travel_width[j];
752
            current_height += travel_height[j];
753

    
754
            /* check if the fragment is in bounds */
755
            if ((current_width < right_edge) &&
756
                (current_height < bottom_edge)) {
757
                s->superblock_fragments[mapping_index] = current_fragment;
758
                debug_init("    mapping fragment %d to superblock %d, position %d (%d/%d x %d/%d)\n", 
759
                    s->superblock_fragments[mapping_index], i, j,
760
                    current_width, right_edge, current_height, bottom_edge);
761
            } else {
762
                s->superblock_fragments[mapping_index] = -1;
763
                debug_init("    superblock %d, position %d has no fragment (%d/%d x %d/%d)\n", 
764
                    i, j,
765
                    current_width, right_edge, current_height, bottom_edge);
766
            }
767

    
768
            mapping_index++;
769
        }
770
    }
771

    
772
    /* initialize the superblock <-> macroblock mapping; iterate through
773
     * all of the Y plane superblocks to build this mapping */
774
    right_edge = s->macroblock_width;
775
    bottom_edge = s->macroblock_height;
776
    current_width = -1;
777
    current_height = 0;
778
    superblock_row_inc = s->macroblock_width -
779
        (s->y_superblock_width * 2 - s->macroblock_width);;
780
    hilbert = hilbert_walk_mb;
781
    mapping_index = 0;
782
    current_macroblock = -1;
783
    for (i = 0; i < s->u_superblock_start; i++) {
784

    
785
        if (current_width >= right_edge - 1) {
786
            /* reset width and move to next superblock row */
787
            current_width = -1;
788
            current_height += 2;
789

    
790
            /* macroblock is now at the start of a new superblock row */
791
            current_macroblock += superblock_row_inc;
792
        }
793

    
794
        /* iterate through each potential macroblock in the superblock */
795
        for (j = 0; j < 4; j++) {
796
            current_macroblock += hilbert_walk_mb[j];
797
            current_width += travel_width_mb[j];
798
            current_height += travel_height_mb[j];
799

    
800
            /* check if the macroblock is in bounds */
801
            if ((current_width < right_edge) &&
802
                (current_height < bottom_edge)) {
803
                s->superblock_macroblocks[mapping_index] = current_macroblock;
804
                debug_init("    mapping macroblock %d to superblock %d, position %d (%d/%d x %d/%d)\n",
805
                    s->superblock_macroblocks[mapping_index], i, j,
806
                    current_width, right_edge, current_height, bottom_edge);
807
            } else {
808
                s->superblock_macroblocks[mapping_index] = -1;
809
                debug_init("    superblock %d, position %d has no macroblock (%d/%d x %d/%d)\n",
810
                    i, j,
811
                    current_width, right_edge, current_height, bottom_edge);
812
            }
813

    
814
            mapping_index++;
815
        }
816
    }
817

    
818
    /* initialize the macroblock <-> fragment mapping */
819
    current_fragment = 0;
820
    current_macroblock = 0;
821
    mapping_index = 0;
822
    for (i = 0; i < s->fragment_height; i += 2) {
823

    
824
        for (j = 0; j < s->fragment_width; j += 2) {
825

    
826
            debug_init("    macroblock %d contains fragments: ", current_macroblock);
827
            s->all_fragments[current_fragment].macroblock = current_macroblock;
828
            s->macroblock_fragments[mapping_index++] = current_fragment;
829
            debug_init("%d ", current_fragment);
830

    
831
            if (j + 1 < s->fragment_width) {
832
                s->all_fragments[current_fragment + 1].macroblock = current_macroblock;
833
                s->macroblock_fragments[mapping_index++] = current_fragment + 1;
834
                debug_init("%d ", current_fragment + 1);
835
            } else
836
                s->macroblock_fragments[mapping_index++] = -1;
837

    
838
            if (i + 1 < s->fragment_height) {
839
                s->all_fragments[current_fragment + s->fragment_width].macroblock = 
840
                    current_macroblock;
841
                s->macroblock_fragments[mapping_index++] = 
842
                    current_fragment + s->fragment_width;
843
                debug_init("%d ", current_fragment + s->fragment_width);
844
            } else
845
                s->macroblock_fragments[mapping_index++] = -1;
846

    
847
            if ((j + 1 < s->fragment_width) && (i + 1 < s->fragment_height)) {
848
                s->all_fragments[current_fragment + s->fragment_width + 1].macroblock = 
849
                    current_macroblock;
850
                s->macroblock_fragments[mapping_index++] = 
851
                    current_fragment + s->fragment_width + 1;
852
                debug_init("%d ", current_fragment + s->fragment_width + 1);
853
            } else
854
                s->macroblock_fragments[mapping_index++] = -1;
855

    
856
            /* C planes */
857
            c_fragment = s->u_fragment_start + 
858
                (i * s->fragment_width / 4) + (j / 2);
859
            s->all_fragments[c_fragment].macroblock = s->macroblock_count;
860
            s->macroblock_fragments[mapping_index++] = c_fragment;
861
            debug_init("%d ", c_fragment);
862

    
863
            c_fragment = s->v_fragment_start + 
864
                (i * s->fragment_width / 4) + (j / 2);
865
            s->all_fragments[c_fragment].macroblock = s->macroblock_count;
866
            s->macroblock_fragments[mapping_index++] = c_fragment;
867
            debug_init("%d ", c_fragment);
868

    
869
            debug_init("\n");
870

    
871
            if (j + 2 <= s->fragment_width)
872
                current_fragment += 2;
873
            else 
874
                current_fragment++;
875
            current_macroblock++;
876
        }
877

    
878
        current_fragment += s->fragment_width;
879
    }
880

    
881
    return 0;  /* successful path out */
882
}
883

    
884
/*
885
 * This function unpacks a single token (which should be in the range 0..31)
886
 * and returns a zero run (number of zero coefficients in current DCT matrix
887
 * before next non-zero coefficient), the next DCT coefficient, and the
888
 * number of consecutive, non-EOB'd DCT blocks to EOB.
889
 */
890
static void unpack_token(GetBitContext *gb, int token, int *zero_run,
891
                         DCTELEM *coeff, int *eob_run) 
892
{
893
    int sign;
894

    
895
    *zero_run = 0;
896
    *eob_run = 0;
897
    *coeff = 0;
898

    
899
    debug_token("    vp3 token %d: ", token);
900
    switch (token) {
901

    
902
    case 0:
903
        debug_token("DCT_EOB_TOKEN, EOB next block\n");
904
        *eob_run = 1;
905
        break;
906

    
907
    case 1:
908
        debug_token("DCT_EOB_PAIR_TOKEN, EOB next 2 blocks\n");
909
        *eob_run = 2;
910
        break;
911

    
912
    case 2:
913
        debug_token("DCT_EOB_TRIPLE_TOKEN, EOB next 3 blocks\n");
914
        *eob_run = 3;
915
        break;
916

    
917
    case 3:
918
        debug_token("DCT_REPEAT_RUN_TOKEN, ");
919
        *eob_run = get_bits(gb, 2) + 4;
920
        debug_token("EOB the next %d blocks\n", *eob_run);
921
        break;
922

    
923
    case 4:
924
        debug_token("DCT_REPEAT_RUN2_TOKEN, ");
925
        *eob_run = get_bits(gb, 3) + 8;
926
        debug_token("EOB the next %d blocks\n", *eob_run);
927
        break;
928

    
929
    case 5:
930
        debug_token("DCT_REPEAT_RUN3_TOKEN, ");
931
        *eob_run = get_bits(gb, 4) + 16;
932
        debug_token("EOB the next %d blocks\n", *eob_run);
933
        break;
934

    
935
    case 6:
936
        debug_token("DCT_REPEAT_RUN4_TOKEN, ");
937
        *eob_run = get_bits(gb, 12);
938
        debug_token("EOB the next %d blocks\n", *eob_run);
939
        break;
940

    
941
    case 7:
942
        debug_token("DCT_SHORT_ZRL_TOKEN, ");
943
        /* note that this token actually indicates that (3 extra bits) + 1 0s
944
         * should be output; this case specifies a run of (3 EBs) 0s and a
945
         * coefficient of 0. */
946
        *zero_run = get_bits(gb, 3);
947
        *coeff = 0;
948
        debug_token("skip the next %d positions in output matrix\n", *zero_run + 1);
949
        break;
950

    
951
    case 8:
952
        debug_token("DCT_ZRL_TOKEN, ");
953
        /* note that this token actually indicates that (6 extra bits) + 1 0s
954
         * should be output; this case specifies a run of (6 EBs) 0s and a
955
         * coefficient of 0. */
956
        *zero_run = get_bits(gb, 6);
957
        *coeff = 0;
958
        debug_token("skip the next %d positions in output matrix\n", *zero_run + 1);
959
        break;
960

    
961
    case 9:
962
        debug_token("ONE_TOKEN, output 1\n");
963
        *coeff = 1;
964
        break;
965

    
966
    case 10:
967
        debug_token("MINUS_ONE_TOKEN, output -1\n");
968
        *coeff = -1;
969
        break;
970

    
971
    case 11:
972
        debug_token("TWO_TOKEN, output 2\n");
973
        *coeff = 2;
974
        break;
975

    
976
    case 12:
977
        debug_token("MINUS_TWO_TOKEN, output -2\n");
978
        *coeff = -2;
979
        break;
980

    
981
    case 13:
982
    case 14:
983
    case 15:
984
    case 16:
985
        debug_token("LOW_VAL_TOKENS, ");
986
        if (get_bits(gb, 1))
987
            *coeff = -(3 + (token - 13));
988
        else
989
            *coeff = 3 + (token - 13);
990
        debug_token("output %d\n", *coeff);
991
        break;
992

    
993
    case 17:
994
        debug_token("DCT_VAL_CATEGORY3, ");
995
        sign = get_bits(gb, 1);
996
        *coeff = 7 + get_bits(gb, 1);
997
        if (sign)
998
            *coeff = -(*coeff);
999
        debug_token("output %d\n", *coeff);
1000
        break;
1001

    
1002
    case 18:
1003
        debug_token("DCT_VAL_CATEGORY4, ");
1004
        sign = get_bits(gb, 1);
1005
        *coeff = 9 + get_bits(gb, 2);
1006
        if (sign)
1007
            *coeff = -(*coeff);
1008
        debug_token("output %d\n", *coeff);
1009
        break;
1010

    
1011
    case 19:
1012
        debug_token("DCT_VAL_CATEGORY5, ");
1013
        sign = get_bits(gb, 1);
1014
        *coeff = 13 + get_bits(gb, 3);
1015
        if (sign)
1016
            *coeff = -(*coeff);
1017
        debug_token("output %d\n", *coeff);
1018
        break;
1019

    
1020
    case 20:
1021
        debug_token("DCT_VAL_CATEGORY6, ");
1022
        sign = get_bits(gb, 1);
1023
        *coeff = 21 + get_bits(gb, 4);
1024
        if (sign)
1025
            *coeff = -(*coeff);
1026
        debug_token("output %d\n", *coeff);
1027
        break;
1028

    
1029
    case 21:
1030
        debug_token("DCT_VAL_CATEGORY7, ");
1031
        sign = get_bits(gb, 1);
1032
        *coeff = 37 + get_bits(gb, 5);
1033
        if (sign)
1034
            *coeff = -(*coeff);
1035
        debug_token("output %d\n", *coeff);
1036
        break;
1037

    
1038
    case 22:
1039
        debug_token("DCT_VAL_CATEGORY8, ");
1040
        sign = get_bits(gb, 1);
1041
        *coeff = 69 + get_bits(gb, 9);
1042
        if (sign)
1043
            *coeff = -(*coeff);
1044
        debug_token("output %d\n", *coeff);
1045
        break;
1046

    
1047
    case 23:
1048
    case 24:
1049
    case 25:
1050
    case 26:
1051
    case 27:
1052
        debug_token("DCT_RUN_CATEGORY1, ");
1053
        *zero_run = token - 22;
1054
        if (get_bits(gb, 1))
1055
            *coeff = -1;
1056
        else
1057
            *coeff = 1;
1058
        debug_token("output %d 0s, then %d\n", *zero_run, *coeff);
1059
        break;
1060

    
1061
    case 28:
1062
        debug_token("DCT_RUN_CATEGORY1B, ");
1063
        if (get_bits(gb, 1))
1064
            *coeff = -1;
1065
        else
1066
            *coeff = 1;
1067
        *zero_run = 6 + get_bits(gb, 2);
1068
        debug_token("output %d 0s, then %d\n", *zero_run, *coeff);
1069
        break;
1070

    
1071
    case 29:
1072
        debug_token("DCT_RUN_CATEGORY1C, ");
1073
        if (get_bits(gb, 1))
1074
            *coeff = -1;
1075
        else
1076
            *coeff = 1;
1077
        *zero_run = 10 + get_bits(gb, 3);
1078
        debug_token("output %d 0s, then %d\n", *zero_run, *coeff);
1079
        break;
1080

    
1081
    case 30:
1082
        debug_token("DCT_RUN_CATEGORY2, ");
1083
        sign = get_bits(gb, 1);
1084
        *coeff = 2 + get_bits(gb, 1);
1085
        if (sign)
1086
            *coeff = -(*coeff);
1087
        *zero_run = 1;
1088
        debug_token("output %d 0s, then %d\n", *zero_run, *coeff);
1089
        break;
1090

    
1091
    case 31:
1092
        debug_token("DCT_RUN_CATEGORY2, ");
1093
        sign = get_bits(gb, 1);
1094
        *coeff = 2 + get_bits(gb, 1);
1095
        if (sign)
1096
            *coeff = -(*coeff);
1097
        *zero_run = 2 + get_bits(gb, 1);
1098
        debug_token("output %d 0s, then %d\n", *zero_run, *coeff);
1099
        break;
1100

    
1101
    default:
1102
        printf ("  vp3: help! Got a bad token: %d > 31\n", token);
1103
        break;
1104

    
1105
  }
1106
}
1107

    
1108
/*
1109
 * This function wipes out all of the fragment data.
1110
 */
1111
static void init_frame(Vp3DecodeContext *s, GetBitContext *gb)
1112
{
1113
    int i;
1114

    
1115
    /* zero out all of the fragment information */
1116
    s->coded_fragment_list_index = 0;
1117
    for (i = 0; i < s->fragment_count; i++) {
1118
        memset(s->all_fragments[i].coeffs, 0, 64 * sizeof(DCTELEM));
1119
        s->all_fragments[i].coeff_count = 0;
1120
        s->all_fragments[i].last_coeff = 0;
1121
s->all_fragments[i].motion_x = 0xbeef;
1122
s->all_fragments[i].motion_y = 0xbeef;
1123
    }
1124
}
1125

    
1126
/*
1127
 * This function sets of the dequantization tables used for a particular
1128
 * frame.
1129
 */
1130
static void init_dequantizer(Vp3DecodeContext *s)
1131
{
1132

    
1133
    int quality_scale = vp31_quality_threshold[s->quality_index];
1134
    int dc_scale_factor = vp31_dc_scale_factor[s->quality_index];
1135
    int i, j;
1136

    
1137
    debug_vp3("  vp3: initializing dequantization tables\n");
1138

    
1139
    /* 
1140
     * Scale dequantizers:
1141
     *
1142
     *   quantizer * sf
1143
     *   --------------
1144
     *        100
1145
     *
1146
     * where sf = dc_scale_factor for DC quantizer
1147
     *           or quality_scale for AC quantizer
1148
     *
1149
     * Then, saturate the result to a lower limit of MIN_DEQUANT_VAL.
1150
     */
1151
#define SCALER 4
1152

    
1153
    /* scale DC quantizers */
1154
    s->intra_y_dequant[0] = vp31_intra_y_dequant[0] * dc_scale_factor / 100;
1155
    if (s->intra_y_dequant[0] < MIN_DEQUANT_VAL * 2)
1156
        s->intra_y_dequant[0] = MIN_DEQUANT_VAL * 2;
1157
    s->intra_y_dequant[0] *= SCALER;
1158

    
1159
    s->intra_c_dequant[0] = vp31_intra_c_dequant[0] * dc_scale_factor / 100;
1160
    if (s->intra_c_dequant[0] < MIN_DEQUANT_VAL * 2)
1161
        s->intra_c_dequant[0] = MIN_DEQUANT_VAL * 2;
1162
    s->intra_c_dequant[0] *= SCALER;
1163

    
1164
    s->inter_dequant[0] = vp31_inter_dequant[0] * dc_scale_factor / 100;
1165
    if (s->inter_dequant[0] < MIN_DEQUANT_VAL * 4)
1166
        s->inter_dequant[0] = MIN_DEQUANT_VAL * 4;
1167
    s->inter_dequant[0] *= SCALER;
1168

    
1169
    /* scale AC quantizers, zigzag at the same time in preparation for
1170
     * the dequantization phase */
1171
    for (i = 1; i < 64; i++) {
1172

    
1173
        j = zigzag_index[i];
1174

    
1175
        s->intra_y_dequant[j] = vp31_intra_y_dequant[i] * quality_scale / 100;
1176
        if (s->intra_y_dequant[j] < MIN_DEQUANT_VAL)
1177
            s->intra_y_dequant[j] = MIN_DEQUANT_VAL;
1178
        s->intra_y_dequant[j] *= SCALER;
1179

    
1180
        s->intra_c_dequant[j] = vp31_intra_c_dequant[i] * quality_scale / 100;
1181
        if (s->intra_c_dequant[j] < MIN_DEQUANT_VAL)
1182
            s->intra_c_dequant[j] = MIN_DEQUANT_VAL;
1183
        s->intra_c_dequant[j] *= SCALER;
1184

    
1185
        s->inter_dequant[j] = vp31_inter_dequant[i] * quality_scale / 100;
1186
        if (s->inter_dequant[j] < MIN_DEQUANT_VAL * 2)
1187
            s->inter_dequant[j] = MIN_DEQUANT_VAL * 2;
1188
        s->inter_dequant[j] *= SCALER;
1189
    }
1190
    
1191
    memset(s->qscale_table, (FFMAX(s->intra_y_dequant[1], s->intra_c_dequant[1])+8)/16, 512); //FIXME finetune
1192

    
1193
    /* print debug information as requested */
1194
    debug_dequantizers("intra Y dequantizers:\n");
1195
    for (i = 0; i < 8; i++) {
1196
      for (j = i * 8; j < i * 8 + 8; j++) {
1197
        debug_dequantizers(" %4d,", s->intra_y_dequant[j]);
1198
      }
1199
      debug_dequantizers("\n");
1200
    }
1201
    debug_dequantizers("\n");
1202

    
1203
    debug_dequantizers("intra C dequantizers:\n");
1204
    for (i = 0; i < 8; i++) {
1205
      for (j = i * 8; j < i * 8 + 8; j++) {
1206
        debug_dequantizers(" %4d,", s->intra_c_dequant[j]);
1207
      }
1208
      debug_dequantizers("\n");
1209
    }
1210
    debug_dequantizers("\n");
1211

    
1212
    debug_dequantizers("interframe dequantizers:\n");
1213
    for (i = 0; i < 8; i++) {
1214
      for (j = i * 8; j < i * 8 + 8; j++) {
1215
        debug_dequantizers(" %4d,", s->inter_dequant[j]);
1216
      }
1217
      debug_dequantizers("\n");
1218
    }
1219
    debug_dequantizers("\n");
1220
}
1221

    
1222
/*
1223
 * This function is used to fetch runs of 1s or 0s from the bitstream for
1224
 * use in determining which superblocks are fully and partially coded.
1225
 *
1226
 *  Codeword                RunLength
1227
 *  0                       1
1228
 *  10x                     2-3
1229
 *  110x                    4-5
1230
 *  1110xx                  6-9
1231
 *  11110xxx                10-17
1232
 *  111110xxxx              18-33
1233
 *  111111xxxxxxxxxxxx      34-4129
1234
 */
1235
static int get_superblock_run_length(GetBitContext *gb)
1236
{
1237

    
1238
    if (get_bits(gb, 1) == 0)
1239
        return 1;
1240

    
1241
    else if (get_bits(gb, 1) == 0)
1242
        return (2 + get_bits(gb, 1));
1243

    
1244
    else if (get_bits(gb, 1) == 0)
1245
        return (4 + get_bits(gb, 1));
1246

    
1247
    else if (get_bits(gb, 1) == 0)
1248
        return (6 + get_bits(gb, 2));
1249

    
1250
    else if (get_bits(gb, 1) == 0)
1251
        return (10 + get_bits(gb, 3));
1252

    
1253
    else if (get_bits(gb, 1) == 0)
1254
        return (18 + get_bits(gb, 4));
1255

    
1256
    else
1257
        return (34 + get_bits(gb, 12));
1258

    
1259
}
1260

    
1261
/*
1262
 * This function is used to fetch runs of 1s or 0s from the bitstream for
1263
 * use in determining which particular fragments are coded.
1264
 *
1265
 * Codeword                RunLength
1266
 * 0x                      1-2
1267
 * 10x                     3-4
1268
 * 110x                    5-6
1269
 * 1110xx                  7-10
1270
 * 11110xx                 11-14
1271
 * 11111xxxx               15-30
1272
 */
1273
static int get_fragment_run_length(GetBitContext *gb)
1274
{
1275

    
1276
    if (get_bits(gb, 1) == 0)
1277
        return (1 + get_bits(gb, 1));
1278

    
1279
    else if (get_bits(gb, 1) == 0)
1280
        return (3 + get_bits(gb, 1));
1281

    
1282
    else if (get_bits(gb, 1) == 0)
1283
        return (5 + get_bits(gb, 1));
1284

    
1285
    else if (get_bits(gb, 1) == 0)
1286
        return (7 + get_bits(gb, 2));
1287

    
1288
    else if (get_bits(gb, 1) == 0)
1289
        return (11 + get_bits(gb, 2));
1290

    
1291
    else
1292
        return (15 + get_bits(gb, 4));
1293

    
1294
}
1295

    
1296
/*
1297
 * This function decodes a VLC from the bitstream and returns a number
1298
 * that ranges from 0..7. The number indicates which of the 8 coding
1299
 * modes to use.
1300
 *
1301
 *  VLC       Number
1302
 *  0            0
1303
 *  10           1
1304
 *  110          2
1305
 *  1110         3
1306
 *  11110        4
1307
 *  111110       5
1308
 *  1111110      6
1309
 *  1111111      7
1310
 *
1311
 */
1312
static int get_mode_code(GetBitContext *gb)
1313
{
1314

    
1315
    if (get_bits(gb, 1) == 0)
1316
        return 0;
1317

    
1318
    else if (get_bits(gb, 1) == 0)
1319
        return 1;
1320

    
1321
    else if (get_bits(gb, 1) == 0)
1322
        return 2;
1323

    
1324
    else if (get_bits(gb, 1) == 0)
1325
        return 3;
1326

    
1327
    else if (get_bits(gb, 1) == 0)
1328
        return 4;
1329

    
1330
    else if (get_bits(gb, 1) == 0)
1331
        return 5;
1332

    
1333
    else if (get_bits(gb, 1) == 0)
1334
        return 6;
1335

    
1336
    else
1337
        return 7;
1338

    
1339
}
1340

    
1341
/*
1342
 * This function extracts a motion vector from the bitstream using a VLC
1343
 * scheme. 3 bits are fetched from the bitstream and 1 of 8 actions is
1344
 * taken depending on the value on those 3 bits:
1345
 *
1346
 *  0: return 0
1347
 *  1: return 1
1348
 *  2: return -1
1349
 *  3: if (next bit is 1) return -2, else return 2
1350
 *  4: if (next bit is 1) return -3, else return 3
1351
 *  5: return 4 + (next 2 bits), next bit is sign
1352
 *  6: return 8 + (next 3 bits), next bit is sign
1353
 *  7: return 16 + (next 4 bits), next bit is sign
1354
 */
1355
static int get_motion_vector_vlc(GetBitContext *gb)
1356
{
1357
    int bits;
1358

    
1359
    bits = get_bits(gb, 3);
1360

    
1361
    switch(bits) {
1362

    
1363
    case 0:
1364
        bits = 0;
1365
        break;
1366

    
1367
    case 1:
1368
        bits = 1;
1369
        break;
1370

    
1371
    case 2:
1372
        bits = -1;
1373
        break;
1374

    
1375
    case 3:
1376
        if (get_bits(gb, 1) == 0)
1377
            bits = 2;
1378
        else
1379
            bits = -2;
1380
        break;
1381

    
1382
    case 4:
1383
        if (get_bits(gb, 1) == 0)
1384
            bits = 3;
1385
        else
1386
            bits = -3;
1387
        break;
1388

    
1389
    case 5:
1390
        bits = 4 + get_bits(gb, 2);
1391
        if (get_bits(gb, 1) == 1)
1392
            bits = -bits;
1393
        break;
1394

    
1395
    case 6:
1396
        bits = 8 + get_bits(gb, 3);
1397
        if (get_bits(gb, 1) == 1)
1398
            bits = -bits;
1399
        break;
1400

    
1401
    case 7:
1402
        bits = 16 + get_bits(gb, 4);
1403
        if (get_bits(gb, 1) == 1)
1404
            bits = -bits;
1405
        break;
1406

    
1407
    }
1408

    
1409
    return bits;
1410
}
1411

    
1412
/*
1413
 * This function fetches a 5-bit number from the stream followed by
1414
 * a sign and calls it a motion vector.
1415
 */
1416
static int get_motion_vector_fixed(GetBitContext *gb)
1417
{
1418

    
1419
    int bits;
1420

    
1421
    bits = get_bits(gb, 5);
1422

    
1423
    if (get_bits(gb, 1) == 1)
1424
        bits = -bits;
1425

    
1426
    return bits;
1427
}
1428

    
1429
/*
1430
 * This function unpacks all of the superblock/macroblock/fragment coding 
1431
 * information from the bitstream.
1432
 */
1433
static int unpack_superblocks(Vp3DecodeContext *s, GetBitContext *gb)
1434
{
1435
    int bit = 0;
1436
    int current_superblock = 0;
1437
    int current_run = 0;
1438
    int decode_fully_flags = 0;
1439
    int decode_partial_blocks = 0;
1440
    int first_c_fragment_seen;
1441

    
1442
    int i, j;
1443
    int current_fragment;
1444

    
1445
    debug_vp3("  vp3: unpacking superblock coding\n");
1446

    
1447
    if (s->keyframe) {
1448

    
1449
        debug_vp3("    keyframe-- all superblocks are fully coded\n");
1450
        memset(s->superblock_coding, SB_FULLY_CODED, s->superblock_count);
1451

    
1452
    } else {
1453

    
1454
        /* unpack the list of partially-coded superblocks */
1455
        bit = get_bits(gb, 1);
1456
        /* toggle the bit because as soon as the first run length is 
1457
         * fetched the bit will be toggled again */
1458
        bit ^= 1;
1459
        while (current_superblock < s->superblock_count) {
1460
            if (current_run == 0) {
1461
                bit ^= 1;
1462
                current_run = get_superblock_run_length(gb);
1463
                debug_block_coding("      setting superblocks %d..%d to %s\n",
1464
                    current_superblock,
1465
                    current_superblock + current_run - 1,
1466
                    (bit) ? "partially coded" : "not coded");
1467

    
1468
                /* if any of the superblocks are not partially coded, flag
1469
                 * a boolean to decode the list of fully-coded superblocks */
1470
                if (bit == 0) {
1471
                    decode_fully_flags = 1;
1472
                } else {
1473

    
1474
                    /* make a note of the fact that there are partially coded
1475
                     * superblocks */
1476
                    decode_partial_blocks = 1;
1477
                }
1478
            }
1479
            s->superblock_coding[current_superblock++] = 
1480
                (bit) ? SB_PARTIALLY_CODED : SB_NOT_CODED;
1481
            current_run--;
1482
        }
1483

    
1484
        /* unpack the list of fully coded superblocks if any of the blocks were
1485
         * not marked as partially coded in the previous step */
1486
        if (decode_fully_flags) {
1487

    
1488
            current_superblock = 0;
1489
            current_run = 0;
1490
            bit = get_bits(gb, 1);
1491
            /* toggle the bit because as soon as the first run length is 
1492
             * fetched the bit will be toggled again */
1493
            bit ^= 1;
1494
            while (current_superblock < s->superblock_count) {
1495

    
1496
                /* skip any superblocks already marked as partially coded */
1497
                if (s->superblock_coding[current_superblock] == SB_NOT_CODED) {
1498

    
1499
                    if (current_run == 0) {
1500
                        bit ^= 1;
1501
                        current_run = get_superblock_run_length(gb);
1502
                    }
1503

    
1504
                    debug_block_coding("      setting superblock %d to %s\n",
1505
                        current_superblock,
1506
                        (bit) ? "fully coded" : "not coded");
1507
                    s->superblock_coding[current_superblock] = 
1508
                        (bit) ? SB_FULLY_CODED : SB_NOT_CODED;
1509
                    current_run--;
1510
                }
1511
                current_superblock++;
1512
            }
1513
        }
1514

    
1515
        /* if there were partial blocks, initialize bitstream for
1516
         * unpacking fragment codings */
1517
        if (decode_partial_blocks) {
1518

    
1519
            current_run = 0;
1520
            bit = get_bits(gb, 1);
1521
            /* toggle the bit because as soon as the first run length is 
1522
             * fetched the bit will be toggled again */
1523
            bit ^= 1;
1524
        }
1525
    }
1526

    
1527
    /* figure out which fragments are coded; iterate through each
1528
     * superblock (all planes) */
1529
    s->coded_fragment_list_index = 0;
1530
    s->first_coded_y_fragment = s->first_coded_c_fragment = 0;
1531
    s->last_coded_y_fragment = s->last_coded_c_fragment = -1;
1532
    first_c_fragment_seen = 0;
1533
    memset(s->macroblock_coding, MODE_COPY, s->macroblock_count);
1534
    for (i = 0; i < s->superblock_count; i++) {
1535

    
1536
        /* iterate through all 16 fragments in a superblock */
1537
        for (j = 0; j < 16; j++) {
1538

    
1539
            /* if the fragment is in bounds, check its coding status */
1540
            current_fragment = s->superblock_fragments[i * 16 + j];
1541
            if (current_fragment >= s->fragment_count) {
1542
                printf ("  vp3:unpack_superblocks(): bad fragment number (%d >= %d)\n",
1543
                    current_fragment, s->fragment_count);
1544
                return 1;
1545
            }
1546
            if (current_fragment != -1) {
1547
                if (s->superblock_coding[i] == SB_NOT_CODED) {
1548

    
1549
                    /* copy all the fragments from the prior frame */
1550
                    s->all_fragments[current_fragment].coding_method = 
1551
                        MODE_COPY;
1552

    
1553
                } else if (s->superblock_coding[i] == SB_PARTIALLY_CODED) {
1554

    
1555
                    /* fragment may or may not be coded; this is the case
1556
                     * that cares about the fragment coding runs */
1557
                    if (current_run == 0) {
1558
                        bit ^= 1;
1559
                        current_run = get_fragment_run_length(gb);
1560
                    }
1561

    
1562
                    if (bit) {
1563
                        /* default mode; actual mode will be decoded in 
1564
                         * the next phase */
1565
                        s->all_fragments[current_fragment].coding_method = 
1566
                            MODE_INTER_NO_MV;
1567
                        s->coded_fragment_list[s->coded_fragment_list_index] = 
1568
                            current_fragment;
1569
                        if ((current_fragment >= s->u_fragment_start) &&
1570
                            (s->last_coded_y_fragment == -1) &&
1571
                            (!first_c_fragment_seen)) {
1572
                            s->first_coded_c_fragment = s->coded_fragment_list_index;
1573
                            s->last_coded_y_fragment = s->first_coded_c_fragment - 1;
1574
                            first_c_fragment_seen = 1;
1575
                        }
1576
                        s->coded_fragment_list_index++;
1577
                        s->macroblock_coding[s->all_fragments[current_fragment].macroblock] = MODE_INTER_NO_MV;
1578
                        debug_block_coding("      superblock %d is partially coded, fragment %d is coded\n",
1579
                            i, current_fragment);
1580
                    } else {
1581
                        /* not coded; copy this fragment from the prior frame */
1582
                        s->all_fragments[current_fragment].coding_method =
1583
                            MODE_COPY;
1584
                        debug_block_coding("      superblock %d is partially coded, fragment %d is not coded\n",
1585
                            i, current_fragment);
1586
                    }
1587

    
1588
                    current_run--;
1589

    
1590
                } else {
1591

    
1592
                    /* fragments are fully coded in this superblock; actual
1593
                     * coding will be determined in next step */
1594
                    s->all_fragments[current_fragment].coding_method = 
1595
                        MODE_INTER_NO_MV;
1596
                    s->coded_fragment_list[s->coded_fragment_list_index] = 
1597
                        current_fragment;
1598
                    if ((current_fragment >= s->u_fragment_start) &&
1599
                        (s->last_coded_y_fragment == -1) &&
1600
                        (!first_c_fragment_seen)) {
1601
                        s->first_coded_c_fragment = s->coded_fragment_list_index;
1602
                        s->last_coded_y_fragment = s->first_coded_c_fragment - 1;
1603
                        first_c_fragment_seen = 1;
1604
                    }
1605
                    s->coded_fragment_list_index++;
1606
                    s->macroblock_coding[s->all_fragments[current_fragment].macroblock] = MODE_INTER_NO_MV;
1607
                    debug_block_coding("      superblock %d is fully coded, fragment %d is coded\n",
1608
                        i, current_fragment);
1609
                }
1610
            }
1611
        }
1612
    }
1613

    
1614
    if (!first_c_fragment_seen)
1615
        /* only Y fragments coded in this frame */
1616
        s->last_coded_y_fragment = s->coded_fragment_list_index - 1;
1617
    else 
1618
        /* end the list of coded C fragments */
1619
        s->last_coded_c_fragment = s->coded_fragment_list_index - 1;
1620

    
1621
    debug_block_coding("    %d total coded fragments, y: %d -> %d, c: %d -> %d\n",
1622
        s->coded_fragment_list_index,
1623
        s->first_coded_y_fragment,
1624
        s->last_coded_y_fragment,
1625
        s->first_coded_c_fragment,
1626
        s->last_coded_c_fragment);
1627

    
1628
    return 0;
1629
}
1630

    
1631
/*
1632
 * This function unpacks all the coding mode data for individual macroblocks
1633
 * from the bitstream.
1634
 */
1635
static int unpack_modes(Vp3DecodeContext *s, GetBitContext *gb)
1636
{
1637
    int i, j, k;
1638
    int scheme;
1639
    int current_macroblock;
1640
    int current_fragment;
1641
    int coding_mode;
1642

    
1643
    debug_vp3("  vp3: unpacking encoding modes\n");
1644

    
1645
    if (s->keyframe) {
1646
        debug_vp3("    keyframe-- all blocks are coded as INTRA\n");
1647

    
1648
        for (i = 0; i < s->fragment_count; i++)
1649
            s->all_fragments[i].coding_method = MODE_INTRA;
1650

    
1651
    } else {
1652

    
1653
        /* fetch the mode coding scheme for this frame */
1654
        scheme = get_bits(gb, 3);
1655
        debug_modes("    using mode alphabet %d\n", scheme);
1656

    
1657
        /* is it a custom coding scheme? */
1658
        if (scheme == 0) {
1659
            debug_modes("    custom mode alphabet ahead:\n");
1660
            for (i = 0; i < 8; i++)
1661
                ModeAlphabet[scheme][get_bits(gb, 3)] = i;
1662
        }
1663

    
1664
        for (i = 0; i < 8; i++)
1665
            debug_modes("      mode[%d][%d] = %d\n", scheme, i, 
1666
                ModeAlphabet[scheme][i]);
1667

    
1668
        /* iterate through all of the macroblocks that contain 1 or more
1669
         * coded fragments */
1670
        for (i = 0; i < s->u_superblock_start; i++) {
1671

    
1672
            for (j = 0; j < 4; j++) {
1673
                current_macroblock = s->superblock_macroblocks[i * 4 + j];
1674
                if ((current_macroblock == -1) ||
1675
                    (s->macroblock_coding[current_macroblock] == MODE_COPY))
1676
                    continue;
1677
                if (current_macroblock >= s->macroblock_count) {
1678
                    printf ("  vp3:unpack_modes(): bad macroblock number (%d >= %d)\n",
1679
                        current_macroblock, s->macroblock_count);
1680
                    return 1;
1681
                }
1682

    
1683
                /* mode 7 means get 3 bits for each coding mode */
1684
                if (scheme == 7)
1685
                    coding_mode = get_bits(gb, 3);
1686
                else
1687
                    coding_mode = ModeAlphabet[scheme][get_mode_code(gb)];
1688

    
1689
                s->macroblock_coding[current_macroblock] = coding_mode;
1690
                for (k = 0; k < 6; k++) {
1691
                    current_fragment = 
1692
                        s->macroblock_fragments[current_macroblock * 6 + k];
1693
                    if (current_fragment == -1)
1694
                        continue;
1695
                    if (current_fragment >= s->fragment_count) {
1696
                        printf ("  vp3:unpack_modes(): bad fragment number (%d >= %d)\n",
1697
                            current_fragment, s->fragment_count);
1698
                        return 1;
1699
                    }
1700
                    if (s->all_fragments[current_fragment].coding_method != 
1701
                        MODE_COPY)
1702
                        s->all_fragments[current_fragment].coding_method =
1703
                            coding_mode;
1704
                }
1705

    
1706
                debug_modes("    coding method for macroblock starting @ fragment %d = %d\n",
1707
                    s->macroblock_fragments[current_macroblock * 6], coding_mode);
1708
            }
1709
        }
1710
    }
1711

    
1712
    return 0;
1713
}
1714

    
1715
/*
1716
 * This function unpacks all the motion vectors for the individual
1717
 * macroblocks from the bitstream.
1718
 */
1719
static int unpack_vectors(Vp3DecodeContext *s, GetBitContext *gb)
1720
{
1721
    int i, j, k;
1722
    int coding_mode;
1723
    int motion_x[6];
1724
    int motion_y[6];
1725
    int last_motion_x = 0;
1726
    int last_motion_y = 0;
1727
    int prior_last_motion_x = 0;
1728
    int prior_last_motion_y = 0;
1729
    int current_macroblock;
1730
    int current_fragment;
1731

    
1732
    debug_vp3("  vp3: unpacking motion vectors\n");
1733
    if (s->keyframe) {
1734

    
1735
        debug_vp3("    keyframe-- there are no motion vectors\n");
1736

    
1737
    } else {
1738

    
1739
        memset(motion_x, 0, 6 * sizeof(int));
1740
        memset(motion_y, 0, 6 * sizeof(int));
1741

    
1742
        /* coding mode 0 is the VLC scheme; 1 is the fixed code scheme */
1743
        coding_mode = get_bits(gb, 1);
1744
        debug_vectors("    using %s scheme for unpacking motion vectors\n",
1745
            (coding_mode == 0) ? "VLC" : "fixed-length");
1746

    
1747
        /* iterate through all of the macroblocks that contain 1 or more
1748
         * coded fragments */
1749
        for (i = 0; i < s->u_superblock_start; i++) {
1750

    
1751
            for (j = 0; j < 4; j++) {
1752
                current_macroblock = s->superblock_macroblocks[i * 4 + j];
1753
                if ((current_macroblock == -1) ||
1754
                    (s->macroblock_coding[current_macroblock] == MODE_COPY))
1755
                    continue;
1756
                if (current_macroblock >= s->macroblock_count) {
1757
                    printf ("  vp3:unpack_vectors(): bad macroblock number (%d >= %d)\n",
1758
                        current_macroblock, s->macroblock_count);
1759
                    return 1;
1760
                }
1761

    
1762
                current_fragment = s->macroblock_fragments[current_macroblock * 6];
1763
                if (current_fragment >= s->fragment_count) {
1764
                    printf ("  vp3:unpack_vectors(): bad fragment number (%d >= %d\n",
1765
                        current_fragment, s->fragment_count);
1766
                    return 1;
1767
                }
1768
                switch (s->macroblock_coding[current_macroblock]) {
1769

    
1770
                case MODE_INTER_PLUS_MV:
1771
                case MODE_GOLDEN_MV:
1772
                    /* all 6 fragments use the same motion vector */
1773
                    if (coding_mode == 0) {
1774
                        motion_x[0] = get_motion_vector_vlc(gb);
1775
                        motion_y[0] = get_motion_vector_vlc(gb);
1776
                    } else {
1777
                        motion_x[0] = get_motion_vector_fixed(gb);
1778
                        motion_y[0] = get_motion_vector_fixed(gb);
1779
                    }
1780
                    for (k = 1; k < 6; k++) {
1781
                        motion_x[k] = motion_x[0];
1782
                        motion_y[k] = motion_y[0];
1783
                    }
1784

    
1785
                    /* vector maintenance, only on MODE_INTER_PLUS_MV */
1786
                    if (s->macroblock_coding[current_macroblock] ==
1787
                        MODE_INTER_PLUS_MV) {
1788
                        prior_last_motion_x = last_motion_x;
1789
                        prior_last_motion_y = last_motion_y;
1790
                        last_motion_x = motion_x[0];
1791
                        last_motion_y = motion_y[0];
1792
                    }
1793
                    break;
1794

    
1795
                case MODE_INTER_FOURMV:
1796
                    /* fetch 4 vectors from the bitstream, one for each
1797
                     * Y fragment, then average for the C fragment vectors */
1798
                    motion_x[4] = motion_y[4] = 0;
1799
                    for (k = 0; k < 4; k++) {
1800
                        if (coding_mode == 0) {
1801
                            motion_x[k] = get_motion_vector_vlc(gb);
1802
                            motion_y[k] = get_motion_vector_vlc(gb);
1803
                        } else {
1804
                            motion_x[k] = get_motion_vector_fixed(gb);
1805
                            motion_y[k] = get_motion_vector_fixed(gb);
1806
                        }
1807
                        motion_x[4] += motion_x[k];
1808
                        motion_y[4] += motion_y[k];
1809
                    }
1810

    
1811
                    if (motion_x[4] >= 0) 
1812
                        motion_x[4] = (motion_x[4] + 2) / 4;
1813
                    else
1814
                        motion_x[4] = (motion_x[4] - 2) / 4;
1815
                    motion_x[5] = motion_x[4];
1816

    
1817
                    if (motion_y[4] >= 0) 
1818
                        motion_y[4] = (motion_y[4] + 2) / 4;
1819
                    else
1820
                        motion_y[4] = (motion_y[4] - 2) / 4;
1821
                    motion_y[5] = motion_y[4];
1822

    
1823
                    /* vector maintenance; vector[3] is treated as the
1824
                     * last vector in this case */
1825
                    prior_last_motion_x = last_motion_x;
1826
                    prior_last_motion_y = last_motion_y;
1827
                    last_motion_x = motion_x[3];
1828
                    last_motion_y = motion_y[3];
1829
                    break;
1830

    
1831
                case MODE_INTER_LAST_MV:
1832
                    /* all 6 fragments use the last motion vector */
1833
                    motion_x[0] = last_motion_x;
1834
                    motion_y[0] = last_motion_y;
1835
                    for (k = 1; k < 6; k++) {
1836
                        motion_x[k] = motion_x[0];
1837
                        motion_y[k] = motion_y[0];
1838
                    }
1839

    
1840
                    /* no vector maintenance (last vector remains the
1841
                     * last vector) */
1842
                    break;
1843

    
1844
                case MODE_INTER_PRIOR_LAST:
1845
                    /* all 6 fragments use the motion vector prior to the
1846
                     * last motion vector */
1847
                    motion_x[0] = prior_last_motion_x;
1848
                    motion_y[0] = prior_last_motion_y;
1849
                    for (k = 1; k < 6; k++) {
1850
                        motion_x[k] = motion_x[0];
1851
                        motion_y[k] = motion_y[0];
1852
                    }
1853

    
1854
                    /* vector maintenance */
1855
                    prior_last_motion_x = last_motion_x;
1856
                    prior_last_motion_y = last_motion_y;
1857
                    last_motion_x = motion_x[0];
1858
                    last_motion_y = motion_y[0];
1859
                    break;
1860

    
1861
                default:
1862
                    /* covers intra, inter without MV, golden without MV */
1863
                    memset(motion_x, 0, 6 * sizeof(int));
1864
                    memset(motion_y, 0, 6 * sizeof(int));
1865

    
1866
                    /* no vector maintenance */
1867
                    break;
1868
                }
1869

    
1870
                /* assign the motion vectors to the correct fragments */
1871
                debug_vectors("    vectors for macroblock starting @ fragment %d (coding method %d):\n",
1872
                    current_fragment,
1873
                    s->macroblock_coding[current_macroblock]);
1874
                for (k = 0; k < 6; k++) {
1875
                    current_fragment = 
1876
                        s->macroblock_fragments[current_macroblock * 6 + k];
1877
                    if (current_fragment == -1)
1878
                        continue;
1879
                    if (current_fragment >= s->fragment_count) {
1880
                        printf ("  vp3:unpack_vectors(): bad fragment number (%d >= %d)\n",
1881
                            current_fragment, s->fragment_count);
1882
                        return 1;
1883
                    }
1884
                    s->all_fragments[current_fragment].motion_x = motion_x[k];
1885
                    s->all_fragments[current_fragment].motion_y = motion_y[k];
1886
                    debug_vectors("    vector %d: fragment %d = (%d, %d)\n",
1887
                        k, current_fragment, motion_x[k], motion_y[k]);
1888
                }
1889
            }
1890
        }
1891
    }
1892

    
1893
    return 0;
1894
}
1895

    
1896
/* 
1897
 * This function is called by unpack_dct_coeffs() to extract the VLCs from
1898
 * the bitstream. The VLCs encode tokens which are used to unpack DCT
1899
 * data. This function unpacks all the VLCs for either the Y plane or both
1900
 * C planes, and is called for DC coefficients or different AC coefficient
1901
 * levels (since different coefficient types require different VLC tables.
1902
 *
1903
 * This function returns a residual eob run. E.g, if a particular token gave
1904
 * instructions to EOB the next 5 fragments and there were only 2 fragments
1905
 * left in the current fragment range, 3 would be returned so that it could
1906
 * be passed into the next call to this same function.
1907
 */
1908
static int unpack_vlcs(Vp3DecodeContext *s, GetBitContext *gb,
1909
                        VLC *table, int coeff_index,
1910
                        int first_fragment, int last_fragment,
1911
                        int eob_run)
1912
{
1913
    int i;
1914
    int token;
1915
    int zero_run;
1916
    DCTELEM coeff;
1917
    Vp3Fragment *fragment;
1918

    
1919
    if ((first_fragment >= s->fragment_count) ||
1920
        (last_fragment >= s->fragment_count)) {
1921

    
1922
        printf ("  vp3:unpack_vlcs(): bad fragment number (%d -> %d ?)\n",
1923
            first_fragment, last_fragment);
1924
        return 0;
1925
    }
1926

    
1927
    for (i = first_fragment; i <= last_fragment; i++) {
1928

    
1929
        fragment = &s->all_fragments[s->coded_fragment_list[i]];
1930
        if (fragment->coeff_count > coeff_index)
1931
            continue;
1932

    
1933
        if (!eob_run) {
1934
            /* decode a VLC into a token */
1935
            token = get_vlc2(gb, table->table, 5, 3);
1936
            debug_vlc(" token = %2d, ", token);
1937
            /* use the token to get a zero run, a coefficient, and an eob run */
1938
            unpack_token(gb, token, &zero_run, &coeff, &eob_run);
1939
        }
1940

    
1941
        if (!eob_run) {
1942
            fragment->coeff_count += zero_run;
1943
            if (fragment->coeff_count < 64)
1944
                fragment->coeffs[fragment->coeff_count++] = coeff;
1945
            debug_vlc(" fragment %d coeff = %d\n",
1946
                s->coded_fragment_list[i], fragment->coeffs[coeff_index]);
1947
        } else {
1948
            fragment->last_coeff = fragment->coeff_count;
1949
            fragment->coeff_count = 64;
1950
            debug_vlc(" fragment %d eob with %d coefficients\n", 
1951
                s->coded_fragment_list[i], fragment->last_coeff);
1952
            eob_run--;
1953
        }
1954
    }
1955

    
1956
    return eob_run;
1957
}
1958

    
1959
/*
1960
 * This function unpacks all of the DCT coefficient data from the
1961
 * bitstream.
1962
 */
1963
static int unpack_dct_coeffs(Vp3DecodeContext *s, GetBitContext *gb)
1964
{
1965
    int i;
1966
    int dc_y_table;
1967
    int dc_c_table;
1968
    int ac_y_table;
1969
    int ac_c_table;
1970
    int residual_eob_run = 0;
1971

    
1972
    /* fetch the DC table indices */
1973
    dc_y_table = get_bits(gb, 4);
1974
    dc_c_table = get_bits(gb, 4);
1975

    
1976
    /* unpack the Y plane DC coefficients */
1977
    debug_vp3("  vp3: unpacking Y plane DC coefficients using table %d\n",
1978
        dc_y_table);
1979
    residual_eob_run = unpack_vlcs(s, gb, &s->dc_vlc[dc_y_table], 0, 
1980
        s->first_coded_y_fragment, s->last_coded_y_fragment, residual_eob_run);
1981

    
1982
    /* unpack the C plane DC coefficients */
1983
    debug_vp3("  vp3: unpacking C plane DC coefficients using table %d\n",
1984
        dc_c_table);
1985
    residual_eob_run = unpack_vlcs(s, gb, &s->dc_vlc[dc_c_table], 0,
1986
        s->first_coded_c_fragment, s->last_coded_c_fragment, residual_eob_run);
1987

    
1988
    /* fetch the AC table indices */
1989
    ac_y_table = get_bits(gb, 4);
1990
    ac_c_table = get_bits(gb, 4);
1991

    
1992
    /* unpack the group 1 AC coefficients (coeffs 1-5) */
1993
    for (i = 1; i <= 5; i++) {
1994

    
1995
        debug_vp3("  vp3: unpacking level %d Y plane AC coefficients using table %d\n",
1996
            i, ac_y_table);
1997
        residual_eob_run = unpack_vlcs(s, gb, &s->ac_vlc_1[ac_y_table], i, 
1998
            s->first_coded_y_fragment, s->last_coded_y_fragment, residual_eob_run);
1999

    
2000
        debug_vp3("  vp3: unpacking level %d C plane AC coefficients using table %d\n",
2001
            i, ac_c_table);
2002
        residual_eob_run = unpack_vlcs(s, gb, &s->ac_vlc_1[ac_c_table], i, 
2003
            s->first_coded_c_fragment, s->last_coded_c_fragment, residual_eob_run);
2004
    }
2005

    
2006
    /* unpack the group 2 AC coefficients (coeffs 6-14) */
2007
    for (i = 6; i <= 14; i++) {
2008

    
2009
        debug_vp3("  vp3: unpacking level %d Y plane AC coefficients using table %d\n",
2010
            i, ac_y_table);
2011
        residual_eob_run = unpack_vlcs(s, gb, &s->ac_vlc_2[ac_y_table], i, 
2012
            s->first_coded_y_fragment, s->last_coded_y_fragment, residual_eob_run);
2013

    
2014
        debug_vp3("  vp3: unpacking level %d C plane AC coefficients using table %d\n",
2015
            i, ac_c_table);
2016
        residual_eob_run = unpack_vlcs(s, gb, &s->ac_vlc_2[ac_c_table], i, 
2017
            s->first_coded_c_fragment, s->last_coded_c_fragment, residual_eob_run);
2018
    }
2019

    
2020
    /* unpack the group 3 AC coefficients (coeffs 15-27) */
2021
    for (i = 15; i <= 27; i++) {
2022

    
2023
        debug_vp3("  vp3: unpacking level %d Y plane AC coefficients using table %d\n",
2024
            i, ac_y_table);
2025
        residual_eob_run = unpack_vlcs(s, gb, &s->ac_vlc_3[ac_y_table], i, 
2026
            s->first_coded_y_fragment, s->last_coded_y_fragment, residual_eob_run);
2027

    
2028
        debug_vp3("  vp3: unpacking level %d C plane AC coefficients using table %d\n",
2029
            i, ac_c_table);
2030
        residual_eob_run = unpack_vlcs(s, gb, &s->ac_vlc_3[ac_c_table], i, 
2031
            s->first_coded_c_fragment, s->last_coded_c_fragment, residual_eob_run);
2032
    }
2033

    
2034
    /* unpack the group 4 AC coefficients (coeffs 28-63) */
2035
    for (i = 28; i <= 63; i++) {
2036

    
2037
        debug_vp3("  vp3: unpacking level %d Y plane AC coefficients using table %d\n",
2038
            i, ac_y_table);
2039
        residual_eob_run = unpack_vlcs(s, gb, &s->ac_vlc_4[ac_y_table], i, 
2040
            s->first_coded_y_fragment, s->last_coded_y_fragment, residual_eob_run);
2041

    
2042
        debug_vp3("  vp3: unpacking level %d C plane AC coefficients using table %d\n",
2043
            i, ac_c_table);
2044
        residual_eob_run = unpack_vlcs(s, gb, &s->ac_vlc_4[ac_c_table], i, 
2045
            s->first_coded_c_fragment, s->last_coded_c_fragment, residual_eob_run);
2046
    }
2047

    
2048
    return 0;
2049
}
2050

    
2051
/*
2052
 * This function reverses the DC prediction for each coded fragment in
2053
 * the frame. Much of this function is adapted directly from the original 
2054
 * VP3 source code.
2055
 */
2056
#define COMPATIBLE_FRAME(x) \
2057
  (compatible_frame[s->all_fragments[x].coding_method] == current_frame_type)
2058
#define FRAME_CODED(x) (s->all_fragments[x].coding_method != MODE_COPY)
2059
static inline int iabs (int x) { return ((x < 0) ? -x : x); }
2060

    
2061
static void reverse_dc_prediction(Vp3DecodeContext *s,
2062
                                  int first_fragment,
2063
                                  int fragment_width,
2064
                                  int fragment_height) 
2065
{
2066

    
2067
#define PUL 8
2068
#define PU 4
2069
#define PUR 2
2070
#define PL 1
2071

    
2072
    int x, y;
2073
    int i = first_fragment;
2074

    
2075
    /*
2076
     * Fragment prediction groups:
2077
     *
2078
     * 32222222226
2079
     * 10000000004
2080
     * 10000000004
2081
     * 10000000004
2082
     * 10000000004
2083
     *
2084
     * Note: Groups 5 and 7 do not exist as it would mean that the 
2085
     * fragment's x coordinate is both 0 and (width - 1) at the same time.
2086
     */
2087
    int predictor_group;
2088
    short predicted_dc;
2089

    
2090
    /* validity flags for the left, up-left, up, and up-right fragments */
2091
    int fl, ful, fu, fur;
2092

    
2093
    /* DC values for the left, up-left, up, and up-right fragments */
2094
    int vl, vul, vu, vur;
2095

    
2096
    /* indices for the left, up-left, up, and up-right fragments */
2097
    int l, ul, u, ur;
2098

    
2099
    /* 
2100
     * The 6 fields mean:
2101
     *   0: up-left multiplier
2102
     *   1: up multiplier
2103
     *   2: up-right multiplier
2104
     *   3: left multiplier
2105
     *   4: mask
2106
     *   5: right bit shift divisor (e.g., 7 means >>=7, a.k.a. div by 128)
2107
     */
2108
    int predictor_transform[16][6] = {
2109
        {  0,  0,  0,  0,   0,  0 },
2110
        {  0,  0,  0,  1,   0,  0 },        // PL
2111
        {  0,  0,  1,  0,   0,  0 },        // PUR
2112
        {  0,  0, 53, 75, 127,  7 },        // PUR|PL
2113
        {  0,  1,  0,  0,   0,  0 },        // PU
2114
        {  0,  1,  0,  1,   1,  1 },        // PU|PL
2115
        {  0,  1,  0,  0,   0,  0 },        // PU|PUR
2116
        {  0,  0, 53, 75, 127,  7 },        // PU|PUR|PL
2117
        {  1,  0,  0,  0,   0,  0 },        // PUL
2118
        {  0,  0,  0,  1,   0,  0 },        // PUL|PL
2119
        {  1,  0,  1,  0,   1,  1 },        // PUL|PUR
2120
        {  0,  0, 53, 75, 127,  7 },        // PUL|PUR|PL
2121
        {  0,  1,  0,  0,   0,  0 },        // PUL|PU
2122
        {-26, 29,  0, 29,  31,  5 },        // PUL|PU|PL
2123
        {  3, 10,  3,  0,  15,  4 },        // PUL|PU|PUR
2124
        {-26, 29,  0, 29,  31,  5 }         // PUL|PU|PUR|PL
2125
    };
2126

    
2127
    /* This table shows which types of blocks can use other blocks for
2128
     * prediction. For example, INTRA is the only mode in this table to
2129
     * have a frame number of 0. That means INTRA blocks can only predict
2130
     * from other INTRA blocks. There are 2 golden frame coding types; 
2131
     * blocks encoding in these modes can only predict from other blocks
2132
     * that were encoded with these 1 of these 2 modes. */
2133
    unsigned char compatible_frame[8] = {
2134
        1,    /* MODE_INTER_NO_MV */
2135
        0,    /* MODE_INTRA */
2136
        1,    /* MODE_INTER_PLUS_MV */
2137
        1,    /* MODE_INTER_LAST_MV */
2138
        1,    /* MODE_INTER_PRIOR_MV */
2139
        2,    /* MODE_USING_GOLDEN */
2140
        2,    /* MODE_GOLDEN_MV */
2141
        1     /* MODE_INTER_FOUR_MV */
2142
    };
2143
    int current_frame_type;
2144

    
2145
    /* there is a last DC predictor for each of the 3 frame types */
2146
    short last_dc[3];
2147

    
2148
    int transform = 0;
2149

    
2150
    debug_vp3("  vp3: reversing DC prediction\n");
2151

    
2152
    vul = vu = vur = vl = 0;
2153
    last_dc[0] = last_dc[1] = last_dc[2] = 0;
2154

    
2155
    /* for each fragment row... */
2156
    for (y = 0; y < fragment_height; y++) {
2157

    
2158
        /* for each fragment in a row... */
2159
        for (x = 0; x < fragment_width; x++, i++) {
2160

    
2161
            /* reverse prediction if this block was coded */
2162
            if (s->all_fragments[i].coding_method != MODE_COPY) {
2163

    
2164
                current_frame_type = 
2165
                    compatible_frame[s->all_fragments[i].coding_method];
2166
                predictor_group = (x == 0) + ((y == 0) << 1) +
2167
                    ((x + 1 == fragment_width) << 2);
2168
                debug_dc_pred(" frag %d: group %d, orig DC = %d, ",
2169
                    i, predictor_group, s->all_fragments[i].coeffs[0]);
2170

    
2171
                switch (predictor_group) {
2172

    
2173
                case 0:
2174
                    /* main body of fragments; consider all 4 possible
2175
                     * fragments for prediction */
2176

    
2177
                    /* calculate the indices of the predicting fragments */
2178
                    ul = i - fragment_width - 1;
2179
                    u = i - fragment_width;
2180
                    ur = i - fragment_width + 1;
2181
                    l = i - 1;
2182

    
2183
                    /* fetch the DC values for the predicting fragments */
2184
                    vul = s->all_fragments[ul].coeffs[0];
2185
                    vu = s->all_fragments[u].coeffs[0];
2186
                    vur = s->all_fragments[ur].coeffs[0];
2187
                    vl = s->all_fragments[l].coeffs[0];
2188

    
2189
                    /* figure out which fragments are valid */
2190
                    ful = FRAME_CODED(ul) && COMPATIBLE_FRAME(ul);
2191
                    fu = FRAME_CODED(u) && COMPATIBLE_FRAME(u);
2192
                    fur = FRAME_CODED(ur) && COMPATIBLE_FRAME(ur);
2193
                    fl = FRAME_CODED(l) && COMPATIBLE_FRAME(l);
2194

    
2195
                    /* decide which predictor transform to use */
2196
                    transform = (fl*PL) | (fu*PU) | (ful*PUL) | (fur*PUR);
2197

    
2198
                    break;
2199

    
2200
                case 1:
2201
                    /* left column of fragments, not including top corner;
2202
                     * only consider up and up-right fragments */
2203

    
2204
                    /* calculate the indices of the predicting fragments */
2205
                    u = i - fragment_width;
2206
                    ur = i - fragment_width + 1;
2207

    
2208
                    /* fetch the DC values for the predicting fragments */
2209
                    vu = s->all_fragments[u].coeffs[0];
2210
                    vur = s->all_fragments[ur].coeffs[0];
2211

    
2212
                    /* figure out which fragments are valid */
2213
                    fur = FRAME_CODED(ur) && COMPATIBLE_FRAME(ur);
2214
                    fu = FRAME_CODED(u) && COMPATIBLE_FRAME(u);
2215

    
2216
                    /* decide which predictor transform to use */
2217
                    transform = (fu*PU) | (fur*PUR);
2218

    
2219
                    break;
2220

    
2221
                case 2:
2222
                case 6:
2223
                    /* top row of fragments, not including top-left frag;
2224
                     * only consider the left fragment for prediction */
2225

    
2226
                    /* calculate the indices of the predicting fragments */
2227
                    l = i - 1;
2228

    
2229
                    /* fetch the DC values for the predicting fragments */
2230
                    vl = s->all_fragments[l].coeffs[0];
2231

    
2232
                    /* figure out which fragments are valid */
2233
                    fl = FRAME_CODED(l) && COMPATIBLE_FRAME(l);
2234

    
2235
                    /* decide which predictor transform to use */
2236
                    transform = (fl*PL);
2237

    
2238
                    break;
2239

    
2240
                case 3:
2241
                    /* top-left fragment */
2242

    
2243
                    /* nothing to predict from in this case */
2244
                    transform = 0;
2245

    
2246
                    break;
2247

    
2248
                case 4:
2249
                    /* right column of fragments, not including top corner;
2250
                     * consider up-left, up, and left fragments for
2251
                     * prediction */
2252

    
2253
                    /* calculate the indices of the predicting fragments */
2254
                    ul = i - fragment_width - 1;
2255
                    u = i - fragment_width;
2256
                    l = i - 1;
2257

    
2258
                    /* fetch the DC values for the predicting fragments */
2259
                    vul = s->all_fragments[ul].coeffs[0];
2260
                    vu = s->all_fragments[u].coeffs[0];
2261
                    vl = s->all_fragments[l].coeffs[0];
2262

    
2263
                    /* figure out which fragments are valid */
2264
                    ful = FRAME_CODED(ul) && COMPATIBLE_FRAME(ul);
2265
                    fu = FRAME_CODED(u) && COMPATIBLE_FRAME(u);
2266
                    fl = FRAME_CODED(l) && COMPATIBLE_FRAME(l);
2267

    
2268
                    /* decide which predictor transform to use */
2269
                    transform = (fl*PL) | (fu*PU) | (ful*PUL);
2270

    
2271
                    break;
2272

    
2273
                }
2274

    
2275
                debug_dc_pred("transform = %d, ", transform);
2276

    
2277
                if (transform == 0) {
2278

    
2279
                    /* if there were no fragments to predict from, use last
2280
                     * DC saved */
2281
                    s->all_fragments[i].coeffs[0] += last_dc[current_frame_type];
2282
                    debug_dc_pred("from last DC (%d) = %d\n", 
2283
                        current_frame_type, s->all_fragments[i].coeffs[0]);
2284

    
2285
                } else {
2286

    
2287
                    /* apply the appropriate predictor transform */
2288
                    predicted_dc =
2289
                        (predictor_transform[transform][0] * vul) +
2290
                        (predictor_transform[transform][1] * vu) +
2291
                        (predictor_transform[transform][2] * vur) +
2292
                        (predictor_transform[transform][3] * vl);
2293

    
2294
                    /* if there is a shift value in the transform, add
2295
                     * the sign bit before the shift */
2296
                    if (predictor_transform[transform][5] != 0) {
2297
                        predicted_dc += ((predicted_dc >> 15) & 
2298
                            predictor_transform[transform][4]);
2299
                        predicted_dc >>= predictor_transform[transform][5];
2300
                    }
2301

    
2302
                    /* check for outranging on the [ul u l] and
2303
                     * [ul u ur l] predictors */
2304
                    if ((transform == 13) || (transform == 15)) {
2305
                        if (iabs(predicted_dc - vu) > 128)
2306
                            predicted_dc = vu;
2307
                        else if (iabs(predicted_dc - vl) > 128)
2308
                            predicted_dc = vl;
2309
                        else if (iabs(predicted_dc - vul) > 128)
2310
                            predicted_dc = vul;
2311
                    }
2312

    
2313
                    /* at long last, apply the predictor */
2314
                    s->all_fragments[i].coeffs[0] += predicted_dc;
2315
                    debug_dc_pred("from pred DC = %d\n", 
2316
                    s->all_fragments[i].coeffs[0]);
2317
                }
2318

    
2319
                /* save the DC */
2320
                last_dc[current_frame_type] = s->all_fragments[i].coeffs[0];
2321
            }
2322
        }
2323
    }
2324
}
2325

    
2326
/*
2327
 * This function performs the final rendering of each fragment's data
2328
 * onto the output frame.
2329
 */
2330
static void render_fragments(Vp3DecodeContext *s,
2331
                             int first_fragment,
2332
                             int width,
2333
                             int height,
2334
                             int plane /* 0 = Y, 1 = U, 2 = V */) 
2335
{
2336
    int x, y;
2337
    int m, n;
2338
    int i = first_fragment;
2339
    int16_t *dequantizer;
2340
    unsigned char *output_plane;
2341
    unsigned char *last_plane;
2342
    unsigned char *golden_plane;
2343
    int stride;
2344
    int motion_x, motion_y;
2345
    int upper_motion_limit, lower_motion_limit;
2346
    int motion_halfpel_index;
2347
    uint8_t *motion_source;
2348

    
2349
    debug_vp3("  vp3: rendering final fragments for %s\n",
2350
        (plane == 0) ? "Y plane" : (plane == 1) ? "U plane" : "V plane");
2351

    
2352
    /* set up plane-specific parameters */
2353
    if (plane == 0) {
2354
        dequantizer = s->intra_y_dequant;
2355
        output_plane = s->current_frame.data[0];
2356
        last_plane = s->last_frame.data[0];
2357
        golden_plane = s->golden_frame.data[0];
2358
        stride = -s->current_frame.linesize[0];
2359
        upper_motion_limit = 7 * s->current_frame.linesize[0];
2360
        lower_motion_limit = height * s->current_frame.linesize[0] + width - 8;
2361
    } else if (plane == 1) {
2362
        dequantizer = s->intra_c_dequant;
2363
        output_plane = s->current_frame.data[1];
2364
        last_plane = s->last_frame.data[1];
2365
        golden_plane = s->golden_frame.data[1];
2366
        stride = -s->current_frame.linesize[1];
2367
        upper_motion_limit = 7 * s->current_frame.linesize[1];
2368
        lower_motion_limit = height * s->current_frame.linesize[1] + width - 8;
2369
    } else {
2370
        dequantizer = s->intra_c_dequant;
2371
        output_plane = s->current_frame.data[2];
2372
        last_plane = s->last_frame.data[2];
2373
        golden_plane = s->golden_frame.data[2];
2374
        stride = -s->current_frame.linesize[2];
2375
        upper_motion_limit = 7 * s->current_frame.linesize[2];
2376
        lower_motion_limit = height * s->current_frame.linesize[2] + width - 8;
2377
    }
2378

    
2379
    /* for each fragment row... */
2380
    for (y = 0; y < height; y += 8) {
2381

    
2382
        /* for each fragment in a row... */
2383
        for (x = 0; x < width; x += 8, i++) {
2384

    
2385
            if ((i < 0) || (i >= s->fragment_count)) {
2386
                printf ("  vp3:render_fragments(): bad fragment number (%d)\n", i);
2387
                return;
2388
            }
2389

    
2390
            /* transform if this block was coded */
2391
            if (s->all_fragments[i].coding_method != MODE_COPY) {
2392

    
2393
                if ((s->all_fragments[i].coding_method == MODE_USING_GOLDEN) ||
2394
                    (s->all_fragments[i].coding_method == MODE_GOLDEN_MV))
2395
                    motion_source= golden_plane;
2396
                else 
2397
                    motion_source= last_plane;
2398

    
2399
                motion_source += s->all_fragments[i].first_pixel;
2400
                motion_halfpel_index = 0;
2401

    
2402
                /* sort out the motion vector if this fragment is coded
2403
                 * using a motion vector method */
2404
                if ((s->all_fragments[i].coding_method > MODE_INTRA) &&
2405
                    (s->all_fragments[i].coding_method != MODE_USING_GOLDEN)) {
2406
                    int src_x, src_y;
2407
                    motion_x = s->all_fragments[i].motion_x;
2408
                    motion_y = s->all_fragments[i].motion_y;
2409
                    if(plane){
2410
                        motion_x= (motion_x>>1) | (motion_x&1);
2411
                        motion_y= (motion_y>>1) | (motion_y&1);
2412
                    }
2413

    
2414
                    src_x= (motion_x>>1) + x;
2415
                    src_y= (motion_y>>1) + y;
2416
if ((motion_x == 0xbeef) || (motion_y == 0xbeef))
2417
printf (" help! got beefy vector! (%X, %X)\n", motion_x, motion_y);
2418

    
2419
                    motion_halfpel_index = motion_x & 0x01;
2420
                    motion_source += (motion_x >> 1);
2421

    
2422
//                    motion_y = -motion_y;
2423
                    motion_halfpel_index |= (motion_y & 0x01) << 1;
2424
                    motion_source += ((motion_y >> 1) * stride);
2425

    
2426
                    if(src_x<0 || src_y<0 || src_x + 9 >= width || src_y + 9 >= height){
2427
                        uint8_t *temp= s->edge_emu_buffer;
2428
                        if(stride<0) temp -= 9*stride;
2429

    
2430
                        ff_emulated_edge_mc(temp, motion_source, stride, 9, 9, src_x, src_y, width, height);
2431
                        motion_source= temp;
2432
                    }
2433
                }
2434

    
2435
                /* first, take care of copying a block from either the
2436
                 * previous or the golden frame */
2437
                if (s->all_fragments[i].coding_method != MODE_INTRA) {
2438

    
2439
                    s->dsp.put_no_rnd_pixels_tab[1][motion_halfpel_index](
2440
                        output_plane + s->all_fragments[i].first_pixel,
2441
                        motion_source,
2442
                        stride, 8);
2443
                }
2444

    
2445
                /* dequantize the DCT coefficients */
2446
                debug_idct("fragment %d, coding mode %d, DC = %d, dequant = %d:\n", 
2447
                    i, s->all_fragments[i].coding_method, 
2448
                    s->all_fragments[i].coeffs[0], dequantizer[0]);
2449

    
2450
                /* invert DCT and place (or add) in final output */
2451
                if (s->all_fragments[i].coding_method == MODE_INTRA) {
2452
                    vp3_idct_put(s->all_fragments[i].coeffs, dequantizer,
2453
                        output_plane + s->all_fragments[i].first_pixel,
2454
                        stride);
2455
                } else {
2456
                    vp3_idct_add(s->all_fragments[i].coeffs, dequantizer,
2457
                        output_plane + s->all_fragments[i].first_pixel,
2458
                        stride);
2459
                }
2460

    
2461
                debug_idct("block after idct_%s():\n",
2462
                    (s->all_fragments[i].coding_method == MODE_INTRA)?
2463
                    "put" : "add");
2464
                for (m = 0; m < 8; m++) {
2465
                    for (n = 0; n < 8; n++) {
2466
                        debug_idct(" %3d", *(output_plane + 
2467
                            s->all_fragments[i].first_pixel + (m * stride + n)));
2468
                    }
2469
                    debug_idct("\n");
2470
                }
2471
                debug_idct("\n");
2472

    
2473
            } else {
2474

    
2475
                /* copy directly from the previous frame */
2476
                s->dsp.put_pixels_tab[1][0](
2477
                    output_plane + s->all_fragments[i].first_pixel,
2478
                    last_plane + s->all_fragments[i].first_pixel,
2479
                    stride, 8);
2480

    
2481
            }
2482
        }
2483
    }
2484

    
2485
    emms_c();
2486

    
2487
}
2488

    
2489
/* 
2490
 * This function computes the first pixel addresses for each fragment.
2491
 * This function needs to be invoked after the first frame is allocated
2492
 * so that it has access to the plane strides.
2493
 */
2494
static void vp3_calculate_pixel_addresses(Vp3DecodeContext *s) 
2495
{
2496

    
2497
    int i, x, y;
2498

    
2499
    /* figure out the first pixel addresses for each of the fragments */
2500
    /* Y plane */
2501
    i = 0;
2502
    for (y = s->fragment_height; y > 0; y--) {
2503
        for (x = 0; x < s->fragment_width; x++) {
2504
            s->all_fragments[i++].first_pixel = 
2505
                s->golden_frame.linesize[0] * y * FRAGMENT_PIXELS -
2506
                    s->golden_frame.linesize[0] +
2507
                    x * FRAGMENT_PIXELS;
2508
            debug_init("  fragment %d, first pixel @ %d\n", 
2509
                i-1, s->all_fragments[i-1].first_pixel);
2510
        }
2511
    }
2512

    
2513
    /* U plane */
2514
    i = s->u_fragment_start;
2515
    for (y = s->fragment_height / 2; y > 0; y--) {
2516
        for (x = 0; x < s->fragment_width / 2; x++) {
2517
            s->all_fragments[i++].first_pixel = 
2518
                s->golden_frame.linesize[1] * y * FRAGMENT_PIXELS -
2519
                    s->golden_frame.linesize[1] +
2520
                    x * FRAGMENT_PIXELS;
2521
            debug_init("  fragment %d, first pixel @ %d\n", 
2522
                i-1, s->all_fragments[i-1].first_pixel);
2523
        }
2524
    }
2525

    
2526
    /* V plane */
2527
    i = s->v_fragment_start;
2528
    for (y = s->fragment_height / 2; y > 0; y--) {
2529
        for (x = 0; x < s->fragment_width / 2; x++) {
2530
            s->all_fragments[i++].first_pixel = 
2531
                s->golden_frame.linesize[2] * y * FRAGMENT_PIXELS -
2532
                    s->golden_frame.linesize[2] +
2533
                    x * FRAGMENT_PIXELS;
2534
            debug_init("  fragment %d, first pixel @ %d\n", 
2535
                i-1, s->all_fragments[i-1].first_pixel);
2536
        }
2537
    }
2538
}
2539

    
2540
/*
2541
 * This is the ffmpeg/libavcodec API init function.
2542
 */
2543
static int vp3_decode_init(AVCodecContext *avctx)
2544
{
2545
    Vp3DecodeContext *s = avctx->priv_data;
2546
    int i;
2547
    int c_width;
2548
    int c_height;
2549
    int y_superblock_count;
2550
    int c_superblock_count;
2551

    
2552
    s->avctx = avctx;
2553
#if 0
2554
    s->width = avctx->width;
2555
    s->height = avctx->height;
2556
#else
2557
    s->width = (avctx->width + 15) & 0xFFFFFFF0;
2558
    s->height = (avctx->height + 15) & 0xFFFFFFF0;
2559
#endif
2560
    avctx->pix_fmt = PIX_FMT_YUV420P;
2561
    avctx->has_b_frames = 0;
2562
    dsputil_init(&s->dsp, avctx);
2563

    
2564
    /* initialize to an impossible value which will force a recalculation
2565
     * in the first frame decode */
2566
    s->quality_index = -1;
2567

    
2568
    s->y_superblock_width = (s->width + 31) / 32;
2569
    s->y_superblock_height = (s->height + 31) / 32;
2570
    y_superblock_count = s->y_superblock_width * s->y_superblock_height;
2571

    
2572
    /* work out the dimensions for the C planes */
2573
    c_width = s->width / 2;
2574
    c_height = s->height / 2;
2575
    s->c_superblock_width = (c_width + 31) / 32;
2576
    s->c_superblock_height = (c_height + 31) / 32;
2577
    c_superblock_count = s->c_superblock_width * s->c_superblock_height;
2578

    
2579
    s->superblock_count = y_superblock_count + (c_superblock_count * 2);
2580
    s->u_superblock_start = y_superblock_count;
2581
    s->v_superblock_start = s->u_superblock_start + c_superblock_count;
2582
    s->superblock_coding = av_malloc(s->superblock_count);
2583

    
2584
    s->macroblock_width = (s->width + 15) / 16;
2585
    s->macroblock_height = (s->height + 15) / 16;
2586
    s->macroblock_count = s->macroblock_width * s->macroblock_height;
2587

    
2588
    s->fragment_width = s->width / FRAGMENT_PIXELS;
2589
    s->fragment_height = s->height / FRAGMENT_PIXELS;
2590

    
2591
    /* fragment count covers all 8x8 blocks for all 3 planes */
2592
    s->fragment_count = s->fragment_width * s->fragment_height * 3 / 2;
2593
    s->u_fragment_start = s->fragment_width * s->fragment_height;
2594
    s->v_fragment_start = s->fragment_width * s->fragment_height * 5 / 4;
2595

    
2596
    debug_init("  Y plane: %d x %d\n", s->width, s->height);
2597
    debug_init("  C plane: %d x %d\n", c_width, c_height);
2598
    debug_init("  Y superblocks: %d x %d, %d total\n",
2599
        s->y_superblock_width, s->y_superblock_height, y_superblock_count);
2600
    debug_init("  C superblocks: %d x %d, %d total\n",
2601
        s->c_superblock_width, s->c_superblock_height, c_superblock_count);
2602
    debug_init("  total superblocks = %d, U starts @ %d, V starts @ %d\n", 
2603
        s->superblock_count, s->u_superblock_start, s->v_superblock_start);
2604
    debug_init("  macroblocks: %d x %d, %d total\n",
2605
        s->macroblock_width, s->macroblock_height, s->macroblock_count);
2606
    debug_init("  %d fragments, %d x %d, u starts @ %d, v starts @ %d\n",
2607
        s->fragment_count,
2608
        s->fragment_width,
2609
        s->fragment_height,
2610
        s->u_fragment_start,
2611
        s->v_fragment_start);
2612

    
2613
    s->all_fragments = av_malloc(s->fragment_count * sizeof(Vp3Fragment));
2614
    s->coded_fragment_list = av_malloc(s->fragment_count * sizeof(int));
2615
    s->pixel_addresses_inited = 0;
2616

    
2617
    /* init VLC tables */
2618
    for (i = 0; i < 16; i++) {
2619

    
2620
        /* DC histograms */
2621
        init_vlc(&s->dc_vlc[i], 5, 32,
2622
            &dc_bias[i][0][1], 4, 2,
2623
            &dc_bias[i][0][0], 4, 2);
2624

    
2625
        /* group 1 AC histograms */
2626
        init_vlc(&s->ac_vlc_1[i], 5, 32,
2627
            &ac_bias_0[i][0][1], 4, 2,
2628
            &ac_bias_0[i][0][0], 4, 2);
2629

    
2630
        /* group 2 AC histograms */
2631
        init_vlc(&s->ac_vlc_2[i], 5, 32,
2632
            &ac_bias_1[i][0][1], 4, 2,
2633
            &ac_bias_1[i][0][0], 4, 2);
2634

    
2635
        /* group 3 AC histograms */
2636
        init_vlc(&s->ac_vlc_3[i], 5, 32,
2637
            &ac_bias_2[i][0][1], 4, 2,
2638
            &ac_bias_2[i][0][0], 4, 2);
2639

    
2640
        /* group 4 AC histograms */
2641
        init_vlc(&s->ac_vlc_4[i], 5, 32,
2642
            &ac_bias_3[i][0][1], 4, 2,
2643
            &ac_bias_3[i][0][0], 4, 2);
2644
    }
2645

    
2646
    /* build quantization zigzag table */
2647
    for (i = 0; i < 64; i++)
2648
        zigzag_index[dezigzag_index[i]] = i;
2649

    
2650
    /* work out the block mapping tables */
2651
    s->superblock_fragments = av_malloc(s->superblock_count * 16 * sizeof(int));
2652
    s->superblock_macroblocks = av_malloc(s->superblock_count * 4 * sizeof(int));
2653
    s->macroblock_fragments = av_malloc(s->macroblock_count * 6 * sizeof(int));
2654
    s->macroblock_coding = av_malloc(s->macroblock_count + 1);
2655
    init_block_mapping(s);
2656

    
2657
    for (i = 0; i < 3; i++) {
2658
        s->current_frame.data[i] = NULL;
2659
        s->last_frame.data[i] = NULL;
2660
        s->golden_frame.data[i] = NULL;
2661
    }
2662

    
2663
    return 0;
2664
}
2665

    
2666
/*
2667
 * This is the ffmpeg/libavcodec API frame decode function.
2668
 */
2669
static int vp3_decode_frame(AVCodecContext *avctx, 
2670
                            void *data, int *data_size,
2671
                            uint8_t *buf, int buf_size)
2672
{
2673
    Vp3DecodeContext *s = avctx->priv_data;
2674
    GetBitContext gb;
2675
    static int counter = 0;
2676

    
2677
    *data_size = 0;
2678

    
2679
    init_get_bits(&gb, buf, buf_size * 8);
2680

    
2681
    s->keyframe = get_bits(&gb, 1);
2682
    s->keyframe ^= 1;
2683
    skip_bits(&gb, 1);
2684
    s->last_quality_index = s->quality_index;
2685
    s->quality_index = get_bits(&gb, 6);
2686

    
2687
    debug_vp3(" VP3 frame #%d: Q index = %d", counter, s->quality_index);
2688
    counter++;
2689

    
2690
    if (s->quality_index != s->last_quality_index)
2691
        init_dequantizer(s);
2692

    
2693
    if (s->keyframe) {
2694

    
2695
        debug_vp3(", keyframe\n");
2696
        /* skip the other 2 header bytes for now */
2697
        skip_bits(&gb, 16);
2698
        if (s->last_frame.data[0] == s->golden_frame.data[0]) {
2699
            if (s->golden_frame.data[0])
2700
                avctx->release_buffer(avctx, &s->golden_frame);
2701
            s->last_frame= s->golden_frame; /* ensure that we catch any access to this released frame */
2702
        } else {
2703
            if (s->golden_frame.data[0])
2704
                avctx->release_buffer(avctx, &s->golden_frame);
2705
            if (s->last_frame.data[0])
2706
                avctx->release_buffer(avctx, &s->last_frame);
2707
        }
2708

    
2709
        s->golden_frame.reference = 3;
2710
        if(avctx->get_buffer(avctx, &s->golden_frame) < 0) {
2711
            printf("vp3: get_buffer() failed\n");
2712
            return -1;
2713
        }
2714

    
2715
        /* golden frame is also the current frame */
2716
        memcpy(&s->current_frame, &s->golden_frame, sizeof(AVFrame));
2717

    
2718
        /* time to figure out pixel addresses? */
2719
        if (!s->pixel_addresses_inited)
2720
            vp3_calculate_pixel_addresses(s);
2721

    
2722
    } else {
2723

    
2724
        debug_vp3("\n");
2725

    
2726
        /* allocate a new current frame */
2727
        s->current_frame.reference = 3;
2728
        if(avctx->get_buffer(avctx, &s->current_frame) < 0) {
2729
            printf("vp3: get_buffer() failed\n");
2730
            return -1;
2731
        }
2732
    }
2733

    
2734
    s->current_frame.qscale_table= s->qscale_table; //FIXME allocate individual tables per AVFrame
2735
    s->current_frame.qstride= 0;
2736

    
2737
    init_frame(s, &gb);
2738

    
2739
#if KEYFRAMES_ONLY
2740
if (!s->keyframe) {
2741

    
2742
    memcpy(s->current_frame.data[0], s->golden_frame.data[0],
2743
        s->current_frame.linesize[0] * s->height);
2744
    memcpy(s->current_frame.data[1], s->golden_frame.data[1],
2745
        s->current_frame.linesize[1] * s->height / 2);
2746
    memcpy(s->current_frame.data[2], s->golden_frame.data[2],
2747
        s->current_frame.linesize[2] * s->height / 2);
2748

    
2749
} else {
2750
#endif
2751

    
2752
    if (unpack_superblocks(s, &gb) ||
2753
        unpack_modes(s, &gb) ||
2754
        unpack_vectors(s, &gb) ||
2755
        unpack_dct_coeffs(s, &gb)) {
2756

    
2757
        printf("  vp3: could not decode frame\n");
2758
        return -1;
2759
    }
2760

    
2761
    reverse_dc_prediction(s, 0, s->fragment_width, s->fragment_height);
2762
    render_fragments(s, 0, s->width, s->height, 0);
2763

    
2764
    if ((avctx->flags & CODEC_FLAG_GRAY) == 0) {
2765
        reverse_dc_prediction(s, s->u_fragment_start,
2766
            s->fragment_width / 2, s->fragment_height / 2);
2767
        reverse_dc_prediction(s, s->v_fragment_start,
2768
            s->fragment_width / 2, s->fragment_height / 2);
2769
        render_fragments(s, s->u_fragment_start, s->width / 2, s->height / 2, 1);
2770
        render_fragments(s, s->v_fragment_start, s->width / 2, s->height / 2, 2);
2771
    } else {
2772
        memset(s->current_frame.data[1], 0x80, s->width * s->height / 4);
2773
        memset(s->current_frame.data[2], 0x80, s->width * s->height / 4);
2774
    }
2775

    
2776
#if KEYFRAMES_ONLY
2777
}
2778
#endif
2779

    
2780
    *data_size=sizeof(AVFrame);
2781
    *(AVFrame*)data= s->current_frame;
2782

    
2783
    /* release the last frame, if it is allocated and if it is not the
2784
     * golden frame */
2785
    if ((s->last_frame.data[0]) &&
2786
        (s->last_frame.data[0] != s->golden_frame.data[0]))
2787
        avctx->release_buffer(avctx, &s->last_frame);
2788

    
2789
    /* shuffle frames (last = current) */
2790
    memcpy(&s->last_frame, &s->current_frame, sizeof(AVFrame));
2791
    s->current_frame.data[0]= NULL; /* ensure that we catch any access to this released frame */
2792

    
2793
    return buf_size;
2794
}
2795

    
2796
/*
2797
 * This is the ffmpeg/libavcodec API module cleanup function.
2798
 */
2799
static int vp3_decode_end(AVCodecContext *avctx)
2800
{
2801
    Vp3DecodeContext *s = avctx->priv_data;
2802

    
2803
    av_free(s->all_fragments);
2804
    av_free(s->coded_fragment_list);
2805
    av_free(s->superblock_fragments);
2806
    av_free(s->superblock_macroblocks);
2807
    av_free(s->macroblock_fragments);
2808
    av_free(s->macroblock_coding);
2809
    
2810
    /* release all frames */
2811
    if (s->golden_frame.data[0] && s->golden_frame.data[0] != s->last_frame.data[0])
2812
        avctx->release_buffer(avctx, &s->golden_frame);
2813
    if (s->last_frame.data[0])
2814
        avctx->release_buffer(avctx, &s->last_frame);
2815
    /* no need to release the current_frame since it will always be pointing
2816
     * to the same frame as either the golden or last frame */
2817

    
2818
    return 0;
2819
}
2820

    
2821
AVCodec vp3_decoder = {
2822
    "vp3",
2823
    CODEC_TYPE_VIDEO,
2824
    CODEC_ID_VP3,
2825
    sizeof(Vp3DecodeContext),
2826
    vp3_decode_init,
2827
    NULL,
2828
    vp3_decode_end,
2829
    vp3_decode_frame,
2830
    0,
2831
    NULL
2832
};