PeerStreamer

/*

 * common functions for Indeo Video Interactive codecs (Indeo4 and Indeo5)

 *

 * Copyright (c) 2009 Maxim Poliakovski

 *

 * This file is part of FFmpeg.

 *

 * FFmpeg is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * FFmpeg is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with FFmpeg; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

/**

 * @file libavcodec/ivi_common.h

 * This file contains structures and macros shared by both Indeo4 and

 * Indeo5 decoders.

 */

#ifndef AVCODEC_IVI_COMMON_H

#define AVCODEC_IVI_COMMON_H

#include "avcodec.h"

#include "get_bits.h"

#include <stdint.h>

#define IVI_DEBUG 0

#define IVI_VLC_BITS 13 ///< max number of bits of the ivi's huffman codes

/**

 *  huffman codebook descriptor

 */

typedef struct {

    int32_t     num_rows;

    uint8_t     xbits[16];

} IVIHuffDesc;

extern const IVIHuffDesc ff_ivi_mb_huff_desc[8];  ///< static macroblock huffman tables

extern const IVIHuffDesc ff_ivi_blk_huff_desc[8]; ///< static block huffman tables

/**

 *  run-value (RLE) table descriptor

 */

typedef struct {

    uint8_t     eob_sym; ///< end of block symbol

    uint8_t     esc_sym; ///< escape symbol

    uint8_t     runtab[256];

    int8_t      valtab[256];

} RVMapDesc;

extern const RVMapDesc ff_ivi_rvmap_tabs[9];

/**

 *  information for Indeo macroblock (16x16, 8x8 or 4x4)

 */

typedef struct {

    int16_t     xpos;

    int16_t     ypos;

    uint32_t    buf_offs; ///< address in the output buffer for this mb

    uint8_t     type;     ///< macroblock type: 0 - INTRA, 1 - INTER

    uint8_t     cbp;      ///< coded block pattern

    uint8_t     q_delta;  ///< quant delta

    int8_t      mv_x;     ///< motion vector (x component)

    int8_t      mv_y;     ///< motion vector (y component)

} IVIMbInfo;

/**

 *  information for Indeo tile

 */

typedef struct {

    int         xpos;

    int         ypos;

    int         width;

    int         height;

    int         is_empty;  ///< = 1 if this tile doesn't contain any data

    int         data_size; ///< size of the data in bytes

    int         num_MBs;   ///< number of macroblocks in this tile

    IVIMbInfo   *mbs;      ///< array of macroblock descriptors

    IVIMbInfo   *ref_mbs;  ///< ptr to the macroblock descriptors of the reference tile

} IVITile;

/**

 *  information for Indeo wavelet band

 */

typedef struct {

    int             plane;          ///< plane number this band belongs to

    int             band_num;       ///< band number

    int             width;

    int             height;

    const uint8_t   *data_ptr;      ///< ptr to the first byte of the band data

    int             data_size;      ///< size of the band data

    int16_t         *buf;           ///< pointer to the output buffer for this band

    int16_t         *ref_buf;       ///< pointer to the reference frame buffer (for motion compensation)

    int16_t         *bufs[3];       ///< array of pointers to the band buffers

    int             pitch;          ///< pitch associated with the buffers above

    int             is_empty;       ///< = 1 if this band doesn't contain any data

    int             mb_size;        ///< macroblock size

    int             blk_size;       ///< block size

    int             is_halfpel;     ///< precision of the motion compensation: 0 - fullpel, 1 - halfpel

    int             inherit_mv;     ///< tells if motion vector is inherited from reference macroblock

    int             inherit_qdelta; ///< tells if quantiser delta is inherited from reference macroblock

    int             qdelta_present; ///< tells if Qdelta signal is present in the bitstream (Indeo5 only)

    int             quant_mat;      ///< dequant matrix index

    int             glob_quant;     ///< quant base for this band

    const uint8_t   *scan;          ///< ptr to the scan pattern

    int             huff_sel;       ///< huffman table for this band

    IVIHuffDesc     huff_desc;      ///< table descriptor associated with the selector above

    VLC             *blk_vlc;       ///< ptr to the vlc table for decoding block data

    VLC             blk_vlc_cust;   ///< custom block vlc table

    uint16_t        *dequant_intra; ///< ptr to dequant tables for intra blocks

    uint16_t        *dequant_inter; ///< ptr dequant tables for inter blocks

    int             num_corr;       ///< number of correction entries

    uint8_t         corr[61*2];     ///< rvmap correction pairs

    int             rvmap_sel;      ///< rvmap table selector

    RVMapDesc       *rv_map;        ///< ptr to the RLE table for this band

    int             num_tiles;      ///< number of tiles in this band

    IVITile         *tiles;         ///< array of tile descriptors

    void (*inv_transform)(const int32_t *in, int16_t *out, uint32_t pitch, const uint8_t *flags); ///< inverse transform function pointer

    void (*dc_transform) (const int32_t *in, int16_t *out, uint32_t pitch, int blk_size);   ///< dc transform function pointer, it may be NULL

    int             is_2d_trans;    ///< 1 indicates that the two-dimensional inverse transform is used

    int32_t         checksum;       ///< for debug purposes

    int             checksum_present;

    int             bufsize;        ///< band buffer size in bytes

    const uint8_t   *intra_base;    ///< quantization matrix for intra blocks

    const uint8_t   *inter_base;    ///< quantization matrix for inter blocks

    const uint8_t   *intra_scale;   ///< quantization coefficient for intra blocks

    const uint8_t   *inter_scale;   ///< quantization coefficient for inter blocks

} IVIBandDesc;

/**

 *  color plane (luma or chroma) information

 */

typedef struct {

    uint16_t    width;

    uint16_t    height;

    uint8_t     num_bands;  ///< number of bands this plane subdivided into

    IVIBandDesc *bands;     ///< array of band descriptors

} IVIPlaneDesc;

typedef struct {

    uint16_t    pic_width;

    uint16_t    pic_height;

    uint16_t    chroma_width;

    uint16_t    chroma_height;

    uint16_t    tile_width;

    uint16_t    tile_height;

    uint8_t     luma_bands;

    uint8_t     chroma_bands;

} IVIPicConfig;

/** compares some properties of two pictures */

static inline int ivi_pic_config_cmp(IVIPicConfig *str1, IVIPicConfig *str2)

{

    return (str1->pic_width    != str2->pic_width    || str1->pic_height    != str2->pic_height    ||

            str1->chroma_width != str2->chroma_width || str1->chroma_height != str2->chroma_height ||

            str1->tile_width   != str2->tile_width   || str1->tile_height   != str2->tile_height   ||

            str1->luma_bands   != str2->luma_bands   || str1->chroma_bands  != str2->chroma_bands);

}

/** calculate number of tiles in a stride */

#define IVI_NUM_TILES(stride, tile_size) (((stride) + (tile_size) - 1) / (tile_size))

/** calculate number of macroblocks in a tile */

#define IVI_MBs_PER_TILE(tile_width, tile_height, mb_size) \

    ((((tile_width) + (mb_size) - 1) / (mb_size)) * (((tile_height) + (mb_size) - 1) / (mb_size)))

/** convert unsigned values into signed ones (the sign is in the LSB) */

#define IVI_TOSIGNED(val) (-(((val) >> 1) ^ -((val) & 1)))

/** scales motion vector */

static inline int ivi_scale_mv(int mv, int mv_scale)

{

    return (mv + (mv > 0) + (mv_scale - 1)) >> mv_scale;

}

/**

 *  Generates a huffman codebook from the given descriptor

 *  and converts it into the FFmpeg VLC table.

 *

 *  @param cb   [in]  pointer to codebook descriptor

 *  @param vlc  [out] where to place the generated VLC table

 *  @param flag [in]  flag: 1 - for static or 0 for dynamic tables

 *  @return     result code: 0 - OK, -1 = error (invalid codebook descriptor)

 */

int  ff_ivi_create_huff_from_desc(const IVIHuffDesc *cb, VLC *vlc, int flag);

/**

 *  Decodes a huffman codebook descriptor from the bitstream.

 *

 *  @param gb   [in,out] the GetBit context

 *  @param desc [out] ptr to descriptor to be filled with data

 *  @return     selector indicating huffman table:

 *              (0...6 - predefined, 7 - custom one supplied with the bitstream)

 */

int  ff_ivi_dec_huff_desc(GetBitContext *gb, IVIHuffDesc *desc);

/**

 *  Compares two huffman codebook descriptors.

 *

 *  @param desc1    [in] ptr to the 1st descriptor to compare

 *  @param desc2    [in] ptr to the 2nd descriptor to compare

 *  @return         comparison result: 0 - equal, 1 - not equal

 */

int  ff_ivi_huff_desc_cmp(const IVIHuffDesc *desc1, const IVIHuffDesc *desc2);

/**

 *  Copies huffman codebook descriptors.

 *

 *  @param dst  [out] ptr to the destination descriptor

 *  @param src  [in]  ptr to the source descriptor

 */

void ff_ivi_huff_desc_copy(IVIHuffDesc *dst, const IVIHuffDesc *src);

/**

 *  Initializes planes (prepares descriptors, allocates buffers etc).

 *

 *  @param planes       [in,out] pointer to the array of the plane descriptors

 *  @param cfg          [in] pointer to the ivi_pic_config structure describing picture layout

 *  @return             result code: 0 - OK

 */

int  ff_ivi_init_planes(IVIPlaneDesc *planes, const IVIPicConfig *cfg);

/**

 *  Frees planes, bands and macroblocks buffers.

 *

 *  @param planes       [in] pointer to the array of the plane descriptors

 */

void ff_ivi_free_buffers(IVIPlaneDesc *planes);

/**

 *  Initializes tile and macroblock descriptors.

 *

 *  @param planes       [in,out] pointer to the array of the plane descriptors

 *  @param tile_width   [in]     tile width

 *  @param tile_height  [in]     tile height

 *  @return             result code: 0 - OK

 */

int  ff_ivi_init_tiles(IVIPlaneDesc *planes, int tile_width, int tile_height);

/**

 *  Decodes size of the tile data.

 *  The size is stored as a variable-length field having the following format:

 *  if (tile_data_size < 255) than this field is only one byte long

 *  if (tile_data_size >= 255) than this field four is byte long: 0xFF X1 X2 X3

 *  where X1-X3 is size of the tile data

 *

 *  @param gb   [in,out] the GetBit context

 *  @return     size of the tile data in bytes

 */

int  ff_ivi_dec_tile_data_size(GetBitContext *gb);

/**

 *  Decodes block data:

 *  extracts huffman-coded transform coefficients from the bitstream,

 *  dequantizes them, applies inverse transform and motion compensation

 *  in order to reconstruct the picture.

 *

 *  @param gb   [in,out] the GetBit context

 *  @param band [in]     pointer to the band descriptor

 *  @param tile [in]     pointer to the tile descriptor

 *  @return     result code: 0 - OK, -1 = error (corrupted blocks data)

 */

int  ff_ivi_decode_blocks(GetBitContext *gb, IVIBandDesc *band, IVITile *tile);

/**

 *  Handles empty tiles by performing data copying and motion

 *  compensation respectively.

 *

 *  @param avctx    [in] ptr to the AVCodecContext

 *  @param band     [in] pointer to the band descriptor

 *  @param tile     [in] pointer to the tile descriptor

 *  @param mv_scale [in] scaling factor for motion vectors

 */

void ff_ivi_process_empty_tile(AVCodecContext *avctx, IVIBandDesc *band,

                               IVITile *tile, int32_t mv_scale);

/**

 *  Converts and outputs the current plane.

 *  This conversion is done by adding back the bias value of 128

 *  (subtracted in the encoder) and clipping the result.

 *

 *  @param plane        [in]  pointer to the descriptor of the plane being processed

 *  @param dst          [out] pointer to the buffer receiving converted pixels

 *  @param dst_pitch    [in]  pitch for moving to the next y line

 */

void ff_ivi_output_plane(IVIPlaneDesc *plane, uint8_t *dst, int dst_pitch);

#if IVI_DEBUG

/**

 *  Calculates band checksum from band data.

 */

uint16_t ivi_calc_band_checksum (IVIBandDesc *band);

/**

 *  Verifies that band data lies in range.

 */

int ivi_check_band (IVIBandDesc *band, const uint8_t *ref, int pitch);

#endif

#endif /* AVCODEC_IVI_COMMON_H */