ffmpeg / libavcodec / msmpeg4.c @ 1e98dffb
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/*
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* MSMPEG4 backend for ffmpeg encoder and decoder
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* Copyright (c) 2001 Gerard Lantau.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program 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
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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*/
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#include <stdlib.h> |
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#include <stdio.h> |
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#include "common.h" |
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#include "dsputil.h" |
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#include "mpegvideo.h" |
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|
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/*
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* You can also call this codec : MPEG4 with a twist !
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*
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* TODO:
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* - (encoding) select best mv table (two choices)
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* - (encoding) select best vlc/dc table
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* - (decoding) handle slice indication
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*/
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//#define DEBUG
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/* motion vector table */
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typedef struct MVTable { |
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int n;
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const UINT16 *table_mv_code;
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const UINT8 *table_mv_bits;
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const UINT8 *table_mvx;
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const UINT8 *table_mvy;
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UINT16 *table_mv_index; /* encoding: convert mv to index in table_mv */
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VLC vlc; /* decoding: vlc */
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} MVTable; |
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|
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static void msmpeg4_encode_block(MpegEncContext * s, DCTELEM * block, int n); |
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static int msmpeg4_decode_block(MpegEncContext * s, DCTELEM * block, |
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int n, int coded); |
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static int msmpeg4_decode_dc(MpegEncContext * s, int n, int *dir_ptr); |
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static int msmpeg4_decode_motion(MpegEncContext * s, |
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int *mx_ptr, int *my_ptr); |
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|
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#ifdef DEBUG
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int intra_count = 0; |
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int frame_count = 0; |
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#endif
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/* XXX: move it to mpegvideo.h */
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static int init_done = 0; |
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#include "msmpeg4data.h" |
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#ifdef STATS
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const char *st_names[ST_NB] = { |
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"unknown",
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"dc",
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"intra_ac",
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"inter_ac",
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"intra_mb",
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"inter_mb",
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"mv",
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}; |
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|
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int st_current_index = 0; |
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unsigned int st_bit_counts[ST_NB]; |
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unsigned int st_out_bit_counts[ST_NB]; |
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|
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#define set_stat(var) st_current_index = var;
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|
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void print_stats(void) |
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{
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unsigned int total; |
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int i;
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printf("Input:\n");
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total = 0;
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for(i=0;i<ST_NB;i++) |
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total += st_bit_counts[i]; |
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if (total == 0) |
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total = 1;
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for(i=0;i<ST_NB;i++) { |
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printf("%-10s : %10.1f %5.1f%%\n",
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st_names[i], |
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(double)st_bit_counts[i] / 8.0, |
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(double)st_bit_counts[i] * 100.0 / total); |
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} |
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printf("%-10s : %10.1f %5.1f%%\n",
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"total",
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(double)total / 8.0, |
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100.0); |
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printf("Output:\n");
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total = 0;
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for(i=0;i<ST_NB;i++) |
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total += st_out_bit_counts[i]; |
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if (total == 0) |
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total = 1;
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for(i=0;i<ST_NB;i++) { |
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printf("%-10s : %10.1f %5.1f%%\n",
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st_names[i], |
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(double)st_out_bit_counts[i] / 8.0, |
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(double)st_out_bit_counts[i] * 100.0 / total); |
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} |
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printf("%-10s : %10.1f %5.1f%%\n",
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"total",
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(double)total / 8.0, |
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100.0); |
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} |
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#else
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#define set_stat(var)
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#endif
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/* build the table which associate a (x,y) motion vector to a vlc */
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static void init_mv_table(MVTable *tab) |
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{
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int i, x, y;
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tab->table_mv_index = malloc(sizeof(UINT16) * 4096); |
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/* mark all entries as not used */
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for(i=0;i<4096;i++) |
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tab->table_mv_index[i] = tab->n; |
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for(i=0;i<tab->n;i++) { |
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x = tab->table_mvx[i]; |
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y = tab->table_mvy[i]; |
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tab->table_mv_index[(x << 6) | y] = i;
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} |
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} |
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static void code012(PutBitContext *pb, int n) |
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{
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if (n == 0) { |
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put_bits(pb, 1, 0); |
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} else {
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put_bits(pb, 1, 1); |
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put_bits(pb, 1, (n >= 2)); |
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} |
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} |
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/* write MSMPEG4 V3 compatible frame header */
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void msmpeg4_encode_picture_header(MpegEncContext * s, int picture_number) |
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{
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int i;
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align_put_bits(&s->pb); |
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put_bits(&s->pb, 2, s->pict_type - 1); |
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put_bits(&s->pb, 5, s->qscale);
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s->rl_table_index = 2;
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s->rl_chroma_table_index = 1; /* only for I frame */ |
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s->dc_table_index = 1;
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s->mv_table_index = 1; /* only if P frame */ |
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s->use_skip_mb_code = 1; /* only if P frame */ |
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if (s->pict_type == I_TYPE) {
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put_bits(&s->pb, 5, 0x17); /* indicate only one "slice" */ |
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code012(&s->pb, s->rl_chroma_table_index); |
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code012(&s->pb, s->rl_table_index); |
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put_bits(&s->pb, 1, s->dc_table_index);
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s->no_rounding = 1;
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} else {
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put_bits(&s->pb, 1, s->use_skip_mb_code);
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s->rl_chroma_table_index = s->rl_table_index; |
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code012(&s->pb, s->rl_table_index); |
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put_bits(&s->pb, 1, s->dc_table_index);
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put_bits(&s->pb, 1, s->mv_table_index);
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if(s->flipflop_rounding){
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s->no_rounding ^= 1;
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}else{
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s->no_rounding = 0;
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} |
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} |
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if (!init_done) {
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/* init various encoding tables */
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init_done = 1;
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init_mv_table(&mv_tables[0]);
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init_mv_table(&mv_tables[1]);
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for(i=0;i<NB_RL_TABLES;i++) |
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init_rl(&rl_table[i]); |
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} |
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#ifdef DEBUG
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intra_count = 0;
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printf("*****frame %d:\n", frame_count++);
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#endif
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} |
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void msmpeg4_encode_ext_header(MpegEncContext * s)
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{
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if(s->pict_type == P_TYPE)
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{
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return; // P-Frames dont seem to have them and not even a 0 bit |
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} |
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else
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{
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s->flipflop_rounding=1;
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s->bitrate= 910;
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put_bits(&s->pb, 1, 1); // ext header indicator |
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put_bits(&s->pb, 4, 7); // ? |
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put_bits(&s->pb, 11, s->bitrate);
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put_bits(&s->pb, 1, s->flipflop_rounding);
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} |
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} |
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/* predict coded block */
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static inline int coded_block_pred(MpegEncContext * s, int n, UINT8 **coded_block_ptr) |
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{
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int x, y, wrap, pred, a, b, c;
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x = 2 * s->mb_x + 1 + (n & 1); |
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y = 2 * s->mb_y + 1 + ((n & 2) >> 1); |
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wrap = s->mb_width * 2 + 2; |
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/* B C
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* A X
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*/
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a = s->coded_block[(x - 1) + (y) * wrap];
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b = s->coded_block[(x - 1) + (y - 1) * wrap]; |
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c = s->coded_block[(x) + (y - 1) * wrap];
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if (b == c) {
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pred = a; |
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} else {
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pred = c; |
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} |
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/* store value */
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*coded_block_ptr = &s->coded_block[(x) + (y) * wrap]; |
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return pred;
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} |
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static void msmpeg4_encode_motion(MpegEncContext * s, |
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int mx, int my) |
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{
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int code;
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MVTable *mv; |
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/* modulo encoding */
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/* WARNING : you cannot reach all the MVs even with the modulo
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encoding. This is a somewhat strange compromise they took !!! */
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if (mx <= -64) |
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mx += 64;
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else if (mx >= 64) |
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mx -= 64;
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if (my <= -64) |
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my += 64;
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else if (my >= 64) |
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my -= 64;
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mx += 32;
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my += 32;
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#if 0
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if ((unsigned)mx >= 64 ||
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(unsigned)my >= 64)
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fprintf(stderr, "error mx=%d my=%d\n", mx, my);
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#endif
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mv = &mv_tables[s->mv_table_index]; |
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code = mv->table_mv_index[(mx << 6) | my];
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set_stat(ST_MV); |
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put_bits(&s->pb, |
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mv->table_mv_bits[code], |
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mv->table_mv_code[code]); |
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if (code == mv->n) {
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/* escape : code litterally */
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put_bits(&s->pb, 6, mx);
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put_bits(&s->pb, 6, my);
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} |
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} |
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void msmpeg4_encode_mb(MpegEncContext * s,
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DCTELEM block[6][64], |
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int motion_x, int motion_y) |
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{
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int cbp, coded_cbp, i;
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int pred_x, pred_y;
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UINT8 *coded_block; |
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if (!s->mb_intra) {
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/* compute cbp */
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set_stat(ST_INTER_MB); |
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cbp = 0;
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for (i = 0; i < 6; i++) { |
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if (s->block_last_index[i] >= 0) |
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cbp |= 1 << (5 - i); |
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} |
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if (s->use_skip_mb_code && (cbp | motion_x | motion_y) == 0) { |
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/* skip macroblock */
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put_bits(&s->pb, 1, 1); |
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return;
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} |
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if (s->use_skip_mb_code)
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put_bits(&s->pb, 1, 0); /* mb coded */ |
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put_bits(&s->pb, |
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table_mb_non_intra[cbp + 64][1], |
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table_mb_non_intra[cbp + 64][0]); |
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/* motion vector */
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h263_pred_motion(s, 0, &pred_x, &pred_y);
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msmpeg4_encode_motion(s, motion_x - pred_x, |
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motion_y - pred_y); |
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} else {
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/* compute cbp */
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cbp = 0;
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coded_cbp = 0;
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for (i = 0; i < 6; i++) { |
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int val, pred;
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val = (s->block_last_index[i] >= 1);
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cbp |= val << (5 - i);
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if (i < 4) { |
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/* predict value for close blocks only for luma */
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pred = coded_block_pred(s, i, &coded_block); |
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*coded_block = val; |
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val = val ^ pred; |
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} |
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coded_cbp |= val << (5 - i);
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} |
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#if 0
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if (coded_cbp)
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printf("cbp=%x %x\n", cbp, coded_cbp);
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#endif
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if (s->pict_type == I_TYPE) {
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set_stat(ST_INTRA_MB); |
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put_bits(&s->pb, |
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table_mb_intra[coded_cbp][1], table_mb_intra[coded_cbp][0]); |
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} else {
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if (s->use_skip_mb_code)
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put_bits(&s->pb, 1, 0); /* mb coded */ |
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put_bits(&s->pb, |
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table_mb_non_intra[cbp][1],
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table_mb_non_intra[cbp][0]);
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} |
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set_stat(ST_INTRA_MB); |
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put_bits(&s->pb, 1, 0); /* no AC prediction yet */ |
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} |
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for (i = 0; i < 6; i++) { |
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msmpeg4_encode_block(s, block[i], i); |
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} |
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} |
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/* strongly inspirated from MPEG4, but not exactly the same ! */
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void msmpeg4_dc_scale(MpegEncContext * s)
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{
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if (s->qscale < 5){ |
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s->y_dc_scale = 8;
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s->c_dc_scale = 8;
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// s->c_dc_scale = (s->qscale + 13)>>1;
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}else if (s->qscale < 9){ |
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s->y_dc_scale = 2 * s->qscale;
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s->c_dc_scale = (s->qscale + 13)>>1; |
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}else{
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s->y_dc_scale = s->qscale + 8;
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s->c_dc_scale = (s->qscale + 13)>>1; |
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} |
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// this differs for quant >24 from mpeg4
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|
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// if(s->qscale==13) s->c_dc_scale=14;
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|
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// if(s->qscale>=6)
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// printf("%d", s->qscale);
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/* s->c_dc_scale values (found by Michael Nidermayer)
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qscale=2 -> 8 (yes iam sure about that)
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qscale=3 -> 8
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qscale=4 -> 8
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qscale=5 -> 9
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qscale=6 -> 9
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qscale=7 -> 10
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qscale=8 -> 10
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qscale=9 -> 11
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qscale=10-> 11
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*/
|
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} |
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|
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/* dir = 0: left, dir = 1: top prediction */
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static int msmpeg4_pred_dc(MpegEncContext * s, int n, |
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INT16 **dc_val_ptr, int *dir_ptr)
|
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{
|
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int a, b, c, x, y, wrap, pred, scale;
|
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INT16 *dc_val; |
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|
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/* find prediction */
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if (n < 4) { |
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x = 2 * s->mb_x + 1 + (n & 1); |
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y = 2 * s->mb_y + 1 + ((n & 2) >> 1); |
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wrap = s->mb_width * 2 + 2; |
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dc_val = s->dc_val[0];
|
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scale = s->y_dc_scale; |
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} else {
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x = s->mb_x + 1;
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y = s->mb_y + 1;
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wrap = s->mb_width + 2;
|
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dc_val = s->dc_val[n - 4 + 1]; |
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scale = s->c_dc_scale; |
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} |
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|
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/* B C
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* A X
|
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*/
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a = dc_val[(x - 1) + (y) * wrap];
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b = dc_val[(x - 1) + (y - 1) * wrap]; |
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c = dc_val[(x) + (y - 1) * wrap];
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|
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/* XXX: the following solution consumes divisions, but it does not
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necessitate to modify mpegvideo.c. The problem comes from the
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fact they decided to store the quantized DC (which would lead
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to problems if Q could vary !) */
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#ifdef ARCH_X86
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/* using 16bit divisions as they are large enough and 2x as fast */
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asm volatile( |
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"movl %3, %%eax \n\t"
|
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"shrl $1, %%eax \n\t"
|
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"addl %%eax, %2 \n\t"
|
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"addl %%eax, %1 \n\t"
|
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"addl %0, %%eax \n\t"
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"xorl %%edx, %%edx \n\t"
|
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"divw %w3 \n\t"
|
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"movzwl %%ax, %0 \n\t"
|
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"movl %1, %%eax \n\t"
|
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"xorl %%edx, %%edx \n\t"
|
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"divw %w3 \n\t"
|
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"movzwl %%ax, %1 \n\t"
|
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"movl %2, %%eax \n\t"
|
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"xorl %%edx, %%edx \n\t"
|
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"divw %w3 \n\t"
|
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"movzwl %%ax, %2 \n\t"
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: "+r" (a), "+r" (b), "+r" (c) |
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: "r" (scale)
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: "%eax", "%edx" |
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); |
| 463 |
#elif defined (ARCH_ALPHA)
|
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/* Divisions are extremely costly on Alpha; optimize the most
|
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common case. */
|
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if (scale == 8) { |
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a = (a + (8 >> 1)) / 8; |
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b = (b + (8 >> 1)) / 8; |
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c = (c + (8 >> 1)) / 8; |
| 470 |
} else {
|
| 471 |
a = (a + (scale >> 1)) / scale;
|
| 472 |
b = (b + (scale >> 1)) / scale;
|
| 473 |
c = (c + (scale >> 1)) / scale;
|
| 474 |
} |
| 475 |
#else
|
| 476 |
a = (a + (scale >> 1)) / scale;
|
| 477 |
b = (b + (scale >> 1)) / scale;
|
| 478 |
c = (c + (scale >> 1)) / scale;
|
| 479 |
#endif
|
| 480 |
/* XXX: WARNING: they did not choose the same test as MPEG4. This
|
| 481 |
is very important ! */
|
| 482 |
if (abs(a - b) <= abs(b - c)) {
|
| 483 |
pred = c; |
| 484 |
*dir_ptr = 1;
|
| 485 |
} else {
|
| 486 |
pred = a; |
| 487 |
*dir_ptr = 0;
|
| 488 |
} |
| 489 |
|
| 490 |
/* update predictor */
|
| 491 |
*dc_val_ptr = &dc_val[(x) + (y) * wrap]; |
| 492 |
return pred;
|
| 493 |
} |
| 494 |
|
| 495 |
#define DC_MAX 119 |
| 496 |
|
| 497 |
static void msmpeg4_encode_dc(MpegEncContext * s, int level, int n, int *dir_ptr) |
| 498 |
{
|
| 499 |
int sign, code;
|
| 500 |
int pred;
|
| 501 |
INT16 *dc_val; |
| 502 |
|
| 503 |
pred = msmpeg4_pred_dc(s, n, &dc_val, dir_ptr); |
| 504 |
|
| 505 |
/* update predictor */
|
| 506 |
if (n < 4) { |
| 507 |
*dc_val = level * s->y_dc_scale; |
| 508 |
} else {
|
| 509 |
*dc_val = level * s->c_dc_scale; |
| 510 |
} |
| 511 |
|
| 512 |
/* do the prediction */
|
| 513 |
level -= pred; |
| 514 |
|
| 515 |
sign = 0;
|
| 516 |
if (level < 0) { |
| 517 |
level = -level; |
| 518 |
sign = 1;
|
| 519 |
} |
| 520 |
|
| 521 |
code = level; |
| 522 |
if (code > DC_MAX)
|
| 523 |
code = DC_MAX; |
| 524 |
|
| 525 |
if (s->dc_table_index == 0) { |
| 526 |
if (n < 4) { |
| 527 |
put_bits(&s->pb, table0_dc_lum[code][1], table0_dc_lum[code][0]); |
| 528 |
} else {
|
| 529 |
put_bits(&s->pb, table0_dc_chroma[code][1], table0_dc_chroma[code][0]); |
| 530 |
} |
| 531 |
} else {
|
| 532 |
if (n < 4) { |
| 533 |
put_bits(&s->pb, table1_dc_lum[code][1], table1_dc_lum[code][0]); |
| 534 |
} else {
|
| 535 |
put_bits(&s->pb, table1_dc_chroma[code][1], table1_dc_chroma[code][0]); |
| 536 |
} |
| 537 |
} |
| 538 |
|
| 539 |
if (code == DC_MAX)
|
| 540 |
put_bits(&s->pb, 8, level);
|
| 541 |
|
| 542 |
if (level != 0) { |
| 543 |
put_bits(&s->pb, 1, sign);
|
| 544 |
} |
| 545 |
} |
| 546 |
|
| 547 |
/* Encoding of a block. Very similar to MPEG4 except for a different
|
| 548 |
escape coding (same as H263) and more vlc tables.
|
| 549 |
*/
|
| 550 |
static void msmpeg4_encode_block(MpegEncContext * s, DCTELEM * block, int n) |
| 551 |
{
|
| 552 |
int level, run, last, i, j, last_index;
|
| 553 |
int last_non_zero, sign, slevel;
|
| 554 |
int code, run_diff, dc_pred_dir;
|
| 555 |
const RLTable *rl;
|
| 556 |
|
| 557 |
if (s->mb_intra) {
|
| 558 |
set_stat(ST_DC); |
| 559 |
msmpeg4_encode_dc(s, block[0], n, &dc_pred_dir);
|
| 560 |
i = 1;
|
| 561 |
if (n < 4) { |
| 562 |
rl = &rl_table[s->rl_table_index]; |
| 563 |
} else {
|
| 564 |
rl = &rl_table[3 + s->rl_chroma_table_index];
|
| 565 |
} |
| 566 |
run_diff = 0;
|
| 567 |
set_stat(ST_INTRA_AC); |
| 568 |
} else {
|
| 569 |
i = 0;
|
| 570 |
rl = &rl_table[3 + s->rl_table_index];
|
| 571 |
run_diff = 1;
|
| 572 |
set_stat(ST_INTER_AC); |
| 573 |
} |
| 574 |
|
| 575 |
/* AC coefs */
|
| 576 |
last_index = s->block_last_index[n]; |
| 577 |
last_non_zero = i - 1;
|
| 578 |
for (; i <= last_index; i++) {
|
| 579 |
j = zigzag_direct[i]; |
| 580 |
level = block[j]; |
| 581 |
if (level) {
|
| 582 |
run = i - last_non_zero - 1;
|
| 583 |
last = (i == last_index); |
| 584 |
sign = 0;
|
| 585 |
slevel = level; |
| 586 |
if (level < 0) { |
| 587 |
sign = 1;
|
| 588 |
level = -level; |
| 589 |
} |
| 590 |
code = get_rl_index(rl, last, run, level); |
| 591 |
put_bits(&s->pb, rl->table_vlc[code][1], rl->table_vlc[code][0]); |
| 592 |
if (code == rl->n) {
|
| 593 |
int level1, run1;
|
| 594 |
|
| 595 |
level1 = level - rl->max_level[last][run]; |
| 596 |
if (level1 < 1) |
| 597 |
goto esc2;
|
| 598 |
code = get_rl_index(rl, last, run, level1); |
| 599 |
if (code == rl->n) {
|
| 600 |
esc2:
|
| 601 |
put_bits(&s->pb, 1, 0); |
| 602 |
if (level > MAX_LEVEL)
|
| 603 |
goto esc3;
|
| 604 |
run1 = run - rl->max_run[last][level] - run_diff; |
| 605 |
if (run1 < 0) |
| 606 |
goto esc3;
|
| 607 |
code = get_rl_index(rl, last, run1, level); |
| 608 |
if (code == rl->n) {
|
| 609 |
esc3:
|
| 610 |
/* third escape */
|
| 611 |
put_bits(&s->pb, 1, 0); |
| 612 |
put_bits(&s->pb, 1, last);
|
| 613 |
put_bits(&s->pb, 6, run);
|
| 614 |
put_bits(&s->pb, 8, slevel & 0xff); |
| 615 |
} else {
|
| 616 |
/* second escape */
|
| 617 |
put_bits(&s->pb, 1, 1); |
| 618 |
put_bits(&s->pb, rl->table_vlc[code][1], rl->table_vlc[code][0]); |
| 619 |
put_bits(&s->pb, 1, sign);
|
| 620 |
} |
| 621 |
} else {
|
| 622 |
/* first escape */
|
| 623 |
put_bits(&s->pb, 1, 1); |
| 624 |
put_bits(&s->pb, rl->table_vlc[code][1], rl->table_vlc[code][0]); |
| 625 |
put_bits(&s->pb, 1, sign);
|
| 626 |
} |
| 627 |
} else {
|
| 628 |
put_bits(&s->pb, 1, sign);
|
| 629 |
} |
| 630 |
last_non_zero = i; |
| 631 |
} |
| 632 |
} |
| 633 |
} |
| 634 |
|
| 635 |
/****************************************/
|
| 636 |
/* decoding stuff */
|
| 637 |
|
| 638 |
static VLC mb_non_intra_vlc;
|
| 639 |
static VLC mb_intra_vlc;
|
| 640 |
static VLC dc_lum_vlc[2]; |
| 641 |
static VLC dc_chroma_vlc[2]; |
| 642 |
|
| 643 |
/* init all vlc decoding tables */
|
| 644 |
int msmpeg4_decode_init_vlc(MpegEncContext *s)
|
| 645 |
{
|
| 646 |
int i;
|
| 647 |
MVTable *mv; |
| 648 |
|
| 649 |
for(i=0;i<NB_RL_TABLES;i++) { |
| 650 |
init_rl(&rl_table[i]); |
| 651 |
init_vlc_rl(&rl_table[i]); |
| 652 |
} |
| 653 |
for(i=0;i<2;i++) { |
| 654 |
mv = &mv_tables[i]; |
| 655 |
init_vlc(&mv->vlc, 9, mv->n + 1, |
| 656 |
mv->table_mv_bits, 1, 1, |
| 657 |
mv->table_mv_code, 2, 2); |
| 658 |
} |
| 659 |
|
| 660 |
init_vlc(&dc_lum_vlc[0], 9, 120, |
| 661 |
&table0_dc_lum[0][1], 8, 4, |
| 662 |
&table0_dc_lum[0][0], 8, 4); |
| 663 |
init_vlc(&dc_chroma_vlc[0], 9, 120, |
| 664 |
&table0_dc_chroma[0][1], 8, 4, |
| 665 |
&table0_dc_chroma[0][0], 8, 4); |
| 666 |
init_vlc(&dc_lum_vlc[1], 9, 120, |
| 667 |
&table1_dc_lum[0][1], 8, 4, |
| 668 |
&table1_dc_lum[0][0], 8, 4); |
| 669 |
init_vlc(&dc_chroma_vlc[1], 9, 120, |
| 670 |
&table1_dc_chroma[0][1], 8, 4, |
| 671 |
&table1_dc_chroma[0][0], 8, 4); |
| 672 |
|
| 673 |
init_vlc(&mb_non_intra_vlc, 9, 128, |
| 674 |
&table_mb_non_intra[0][1], 8, 4, |
| 675 |
&table_mb_non_intra[0][0], 8, 4); |
| 676 |
init_vlc(&mb_intra_vlc, 9, 64, |
| 677 |
&table_mb_intra[0][1], 4, 2, |
| 678 |
&table_mb_intra[0][0], 4, 2); |
| 679 |
return 0; |
| 680 |
} |
| 681 |
|
| 682 |
static int decode012(GetBitContext *gb) |
| 683 |
{
|
| 684 |
int n;
|
| 685 |
n = get_bits1(gb); |
| 686 |
if (n == 0) |
| 687 |
return 0; |
| 688 |
else
|
| 689 |
return get_bits1(gb) + 1; |
| 690 |
} |
| 691 |
|
| 692 |
int msmpeg4_decode_picture_header(MpegEncContext * s)
|
| 693 |
{
|
| 694 |
int code;
|
| 695 |
|
| 696 |
s->pict_type = get_bits(&s->gb, 2) + 1; |
| 697 |
if (s->pict_type != I_TYPE &&
|
| 698 |
s->pict_type != P_TYPE) |
| 699 |
return -1; |
| 700 |
|
| 701 |
s->qscale = get_bits(&s->gb, 5);
|
| 702 |
|
| 703 |
if (s->pict_type == I_TYPE) {
|
| 704 |
code = get_bits(&s->gb, 5);
|
| 705 |
/* 0x17: one slice, 0x18: three slices */
|
| 706 |
/* XXX: implement it */
|
| 707 |
//printf("%d %d %d\n", code, s->slice_height, s->first_slice_line);
|
| 708 |
if (code < 0x17) |
| 709 |
return -1; |
| 710 |
s->slice_height = s->mb_height / (code - 0x16);
|
| 711 |
s->rl_chroma_table_index = decode012(&s->gb); |
| 712 |
s->rl_table_index = decode012(&s->gb); |
| 713 |
|
| 714 |
s->dc_table_index = get_bits1(&s->gb); |
| 715 |
s->no_rounding = 1;
|
| 716 |
/* printf(" %d %d %d %d \n",
|
| 717 |
s->qscale,
|
| 718 |
s->rl_chroma_table_index,
|
| 719 |
s->rl_table_index,
|
| 720 |
s->dc_table_index);*/
|
| 721 |
} else {
|
| 722 |
s->use_skip_mb_code = get_bits1(&s->gb); |
| 723 |
|
| 724 |
s->rl_table_index = decode012(&s->gb); |
| 725 |
s->rl_chroma_table_index = s->rl_table_index; |
| 726 |
|
| 727 |
s->dc_table_index = get_bits1(&s->gb); |
| 728 |
|
| 729 |
s->mv_table_index = get_bits1(&s->gb); |
| 730 |
/* printf(" %d %d %d %d %d \n",
|
| 731 |
s->use_skip_mb_code,
|
| 732 |
s->rl_table_index,
|
| 733 |
s->rl_chroma_table_index,
|
| 734 |
s->dc_table_index,
|
| 735 |
s->mv_table_index);*/
|
| 736 |
if(s->flipflop_rounding){
|
| 737 |
s->no_rounding ^= 1;
|
| 738 |
}else{
|
| 739 |
s->no_rounding = 0;
|
| 740 |
} |
| 741 |
// printf("%d", s->no_rounding);
|
| 742 |
} |
| 743 |
|
| 744 |
|
| 745 |
#ifdef DEBUG
|
| 746 |
printf("*****frame %d:\n", frame_count++);
|
| 747 |
#endif
|
| 748 |
return 0; |
| 749 |
} |
| 750 |
|
| 751 |
int msmpeg4_decode_ext_header(MpegEncContext * s, int buf_size) |
| 752 |
{
|
| 753 |
int firstBit=0; |
| 754 |
|
| 755 |
/* the alt_bitstream reader could read over the end so we need to check it */
|
| 756 |
if(get_bits_count(&s->gb) < buf_size*8) firstBit= get_bits1(&s->gb); |
| 757 |
|
| 758 |
if(s->pict_type == P_TYPE)
|
| 759 |
{
|
| 760 |
if(firstBit) return -1; // havnt seen ext headers in P-Frames yet ;) |
| 761 |
} |
| 762 |
else
|
| 763 |
{
|
| 764 |
int unk;
|
| 765 |
if(!firstBit) // no header found |
| 766 |
{
|
| 767 |
s->flipflop_rounding= 0;
|
| 768 |
s->bitrate= 0;
|
| 769 |
return 0; |
| 770 |
} |
| 771 |
|
| 772 |
unk= get_bits(&s->gb, 4);
|
| 773 |
s->bitrate= get_bits(&s->gb, 11);
|
| 774 |
|
| 775 |
// printf("%2d %4d ;; %1X\n", unk,s->bitrate, unk);
|
| 776 |
|
| 777 |
s->flipflop_rounding= get_bits1(&s->gb); |
| 778 |
} |
| 779 |
|
| 780 |
return 0; |
| 781 |
} |
| 782 |
|
| 783 |
void memsetw(short *tab, int val, int n) |
| 784 |
{
|
| 785 |
int i;
|
| 786 |
for(i=0;i<n;i++) |
| 787 |
tab[i] = val; |
| 788 |
} |
| 789 |
|
| 790 |
int msmpeg4_decode_mb(MpegEncContext *s,
|
| 791 |
DCTELEM block[6][64]) |
| 792 |
{
|
| 793 |
int cbp, code, i;
|
| 794 |
int pred, val;
|
| 795 |
UINT8 *coded_val; |
| 796 |
|
| 797 |
/* special slice handling */
|
| 798 |
if (s->mb_x == 0) { |
| 799 |
if (s->slice_height && (s->mb_y % s->slice_height) == 0) { |
| 800 |
int wrap;
|
| 801 |
/* reset DC pred (set previous line to 1024) */
|
| 802 |
wrap = 2 * s->mb_width + 2; |
| 803 |
memsetw(&s->dc_val[0][(1) + (2 * s->mb_y) * wrap], |
| 804 |
1024, 2 * s->mb_width); |
| 805 |
wrap = s->mb_width + 2;
|
| 806 |
memsetw(&s->dc_val[1][(1) + (s->mb_y) * wrap], |
| 807 |
1024, s->mb_width);
|
| 808 |
memsetw(&s->dc_val[2][(1) + (s->mb_y) * wrap], |
| 809 |
1024, s->mb_width);
|
| 810 |
|
| 811 |
/* reset AC pred (set previous line to 0) */
|
| 812 |
wrap = s->mb_width * 2 + 2; |
| 813 |
memsetw(s->ac_val[0][0] + (1 + (2 * s->mb_y) * wrap)*16, |
| 814 |
0, 2 * s->mb_width*16); |
| 815 |
wrap = s->mb_width + 2;
|
| 816 |
memsetw(s->ac_val[1][0] + (1 + (s->mb_y) * wrap)*16, |
| 817 |
0, s->mb_width*16); |
| 818 |
memsetw(s->ac_val[2][0] + (1 + (s->mb_y) * wrap)*16, |
| 819 |
0, s->mb_width*16); |
| 820 |
|
| 821 |
s->first_slice_line = 1;
|
| 822 |
} else {
|
| 823 |
s->first_slice_line = 0;
|
| 824 |
} |
| 825 |
} |
| 826 |
|
| 827 |
if (s->pict_type == P_TYPE) {
|
| 828 |
set_stat(ST_INTER_MB); |
| 829 |
if (s->use_skip_mb_code) {
|
| 830 |
if (get_bits1(&s->gb)) {
|
| 831 |
/* skip mb */
|
| 832 |
s->mb_intra = 0;
|
| 833 |
for(i=0;i<6;i++) |
| 834 |
s->block_last_index[i] = -1;
|
| 835 |
s->mv_dir = MV_DIR_FORWARD; |
| 836 |
s->mv_type = MV_TYPE_16X16; |
| 837 |
s->mv[0][0][0] = 0; |
| 838 |
s->mv[0][0][1] = 0; |
| 839 |
s->mb_skiped = 1;
|
| 840 |
return 0; |
| 841 |
} |
| 842 |
} |
| 843 |
|
| 844 |
code = get_vlc(&s->gb, &mb_non_intra_vlc); |
| 845 |
if (code < 0) |
| 846 |
return -1; |
| 847 |
if (code & 0x40) |
| 848 |
s->mb_intra = 0;
|
| 849 |
else
|
| 850 |
s->mb_intra = 1;
|
| 851 |
|
| 852 |
cbp = code & 0x3f;
|
| 853 |
} else {
|
| 854 |
set_stat(ST_INTRA_MB); |
| 855 |
s->mb_intra = 1;
|
| 856 |
code = get_vlc(&s->gb, &mb_intra_vlc); |
| 857 |
if (code < 0) |
| 858 |
return -1; |
| 859 |
/* predict coded block pattern */
|
| 860 |
cbp = 0;
|
| 861 |
for(i=0;i<6;i++) { |
| 862 |
val = ((code >> (5 - i)) & 1); |
| 863 |
if (i < 4) { |
| 864 |
pred = coded_block_pred(s, i, &coded_val); |
| 865 |
val = val ^ pred; |
| 866 |
*coded_val = val; |
| 867 |
} |
| 868 |
cbp |= val << (5 - i);
|
| 869 |
} |
| 870 |
} |
| 871 |
|
| 872 |
if (!s->mb_intra) {
|
| 873 |
int mx, my;
|
| 874 |
set_stat(ST_MV); |
| 875 |
h263_pred_motion(s, 0, &mx, &my);
|
| 876 |
if (msmpeg4_decode_motion(s, &mx, &my) < 0) |
| 877 |
return -1; |
| 878 |
s->mv_dir = MV_DIR_FORWARD; |
| 879 |
s->mv_type = MV_TYPE_16X16; |
| 880 |
s->mv[0][0][0] = mx; |
| 881 |
s->mv[0][0][1] = my; |
| 882 |
} else {
|
| 883 |
set_stat(ST_INTRA_MB); |
| 884 |
s->ac_pred = get_bits1(&s->gb); |
| 885 |
} |
| 886 |
|
| 887 |
for (i = 0; i < 6; i++) { |
| 888 |
if (msmpeg4_decode_block(s, block[i], i, (cbp >> (5 - i)) & 1) < 0) |
| 889 |
return -1; |
| 890 |
} |
| 891 |
return 0; |
| 892 |
} |
| 893 |
|
| 894 |
static int msmpeg4_decode_block(MpegEncContext * s, DCTELEM * block, |
| 895 |
int n, int coded) |
| 896 |
{
|
| 897 |
int code, level, i, j, last, run, run_diff;
|
| 898 |
int dc_pred_dir;
|
| 899 |
RLTable *rl; |
| 900 |
const UINT8 *scan_table;
|
| 901 |
int qmul, qadd;
|
| 902 |
|
| 903 |
if (s->mb_intra) {
|
| 904 |
qmul=1;
|
| 905 |
qadd=0;
|
| 906 |
|
| 907 |
/* DC coef */
|
| 908 |
set_stat(ST_DC); |
| 909 |
level = msmpeg4_decode_dc(s, n, &dc_pred_dir); |
| 910 |
if (level < 0) |
| 911 |
return -1; |
| 912 |
block[0] = level;
|
| 913 |
if (n < 4) { |
| 914 |
rl = &rl_table[s->rl_table_index]; |
| 915 |
} else {
|
| 916 |
rl = &rl_table[3 + s->rl_chroma_table_index];
|
| 917 |
} |
| 918 |
|
| 919 |
run_diff = 0;
|
| 920 |
i = 1;
|
| 921 |
if (!coded) {
|
| 922 |
goto not_coded;
|
| 923 |
} |
| 924 |
if (s->ac_pred) {
|
| 925 |
if (dc_pred_dir == 0) |
| 926 |
scan_table = ff_alternate_vertical_scan; /* left */
|
| 927 |
else
|
| 928 |
scan_table = ff_alternate_horizontal_scan; /* top */
|
| 929 |
} else {
|
| 930 |
scan_table = zigzag_direct; |
| 931 |
} |
| 932 |
set_stat(ST_INTRA_AC); |
| 933 |
} else {
|
| 934 |
qmul = s->qscale << 1;
|
| 935 |
qadd = (s->qscale - 1) | 1; |
| 936 |
i = 0;
|
| 937 |
rl = &rl_table[3 + s->rl_table_index];
|
| 938 |
run_diff = 1;
|
| 939 |
if (!coded) {
|
| 940 |
s->block_last_index[n] = i - 1;
|
| 941 |
return 0; |
| 942 |
} |
| 943 |
scan_table = zigzag_direct; |
| 944 |
set_stat(ST_INTER_AC); |
| 945 |
} |
| 946 |
|
| 947 |
for(;;) {
|
| 948 |
code = get_vlc(&s->gb, &rl->vlc); |
| 949 |
if (code < 0) |
| 950 |
return -1; |
| 951 |
if (code == rl->n) {
|
| 952 |
/* escape */
|
| 953 |
if (get_bits1(&s->gb) == 0) { |
| 954 |
if (get_bits1(&s->gb) == 0) { |
| 955 |
/* third escape */
|
| 956 |
last = get_bits1(&s->gb); |
| 957 |
run = get_bits(&s->gb, 6);
|
| 958 |
level = get_bits(&s->gb, 8);
|
| 959 |
level = (level << 24) >> 24; /* sign extend */ |
| 960 |
if(level>0) level= level * qmul + qadd; |
| 961 |
else level= level * qmul - qadd;
|
| 962 |
} else {
|
| 963 |
/* second escape */
|
| 964 |
code = get_vlc(&s->gb, &rl->vlc); |
| 965 |
if (code < 0 || code >= rl->n) |
| 966 |
return -1; |
| 967 |
run = rl->table_run[code]; |
| 968 |
level = rl->table_level[code]; |
| 969 |
last = code >= rl->last; |
| 970 |
run += rl->max_run[last][level] + run_diff; |
| 971 |
level= level * qmul + qadd; |
| 972 |
if (get_bits1(&s->gb))
|
| 973 |
level = -level; |
| 974 |
} |
| 975 |
} else {
|
| 976 |
/* first escape */
|
| 977 |
code = get_vlc(&s->gb, &rl->vlc); |
| 978 |
if (code < 0 || code >= rl->n) |
| 979 |
return -1; |
| 980 |
run = rl->table_run[code]; |
| 981 |
level = rl->table_level[code]; |
| 982 |
last = code >= rl->last; |
| 983 |
level += rl->max_level[last][run]; |
| 984 |
level= level * qmul + qadd; |
| 985 |
if (get_bits1(&s->gb))
|
| 986 |
level = -level; |
| 987 |
} |
| 988 |
} else {
|
| 989 |
run = rl->table_run[code]; |
| 990 |
level = rl->table_level[code] * qmul + qadd; |
| 991 |
last = code >= rl->last; |
| 992 |
if (get_bits1(&s->gb))
|
| 993 |
level = -level; |
| 994 |
} |
| 995 |
i += run; |
| 996 |
if (i >= 64) |
| 997 |
return -1; |
| 998 |
j = scan_table[i]; |
| 999 |
block[j] = level; |
| 1000 |
i++; |
| 1001 |
if (last)
|
| 1002 |
break;
|
| 1003 |
} |
| 1004 |
not_coded:
|
| 1005 |
if (s->mb_intra) {
|
| 1006 |
mpeg4_pred_ac(s, block, n, dc_pred_dir); |
| 1007 |
if (s->ac_pred) {
|
| 1008 |
i = 64; /* XXX: not optimal */ |
| 1009 |
} |
| 1010 |
} |
| 1011 |
s->block_last_index[n] = i - 1;
|
| 1012 |
|
| 1013 |
return 0; |
| 1014 |
} |
| 1015 |
|
| 1016 |
static int msmpeg4_decode_dc(MpegEncContext * s, int n, int *dir_ptr) |
| 1017 |
{
|
| 1018 |
int level, pred;
|
| 1019 |
INT16 *dc_val; |
| 1020 |
|
| 1021 |
if (n < 4) { |
| 1022 |
level = get_vlc(&s->gb, &dc_lum_vlc[s->dc_table_index]); |
| 1023 |
} else {
|
| 1024 |
level = get_vlc(&s->gb, &dc_chroma_vlc[s->dc_table_index]); |
| 1025 |
} |
| 1026 |
if (level < 0) |
| 1027 |
return -1; |
| 1028 |
|
| 1029 |
if (level == DC_MAX) {
|
| 1030 |
level = get_bits(&s->gb, 8);
|
| 1031 |
if (get_bits1(&s->gb))
|
| 1032 |
level = -level; |
| 1033 |
} else if (level != 0) { |
| 1034 |
if (get_bits1(&s->gb))
|
| 1035 |
level = -level; |
| 1036 |
} |
| 1037 |
|
| 1038 |
pred = msmpeg4_pred_dc(s, n, &dc_val, dir_ptr); |
| 1039 |
level += pred; |
| 1040 |
|
| 1041 |
/* update predictor */
|
| 1042 |
if (n < 4) { |
| 1043 |
*dc_val = level * s->y_dc_scale; |
| 1044 |
} else {
|
| 1045 |
*dc_val = level * s->c_dc_scale; |
| 1046 |
} |
| 1047 |
|
| 1048 |
return level;
|
| 1049 |
} |
| 1050 |
|
| 1051 |
static int msmpeg4_decode_motion(MpegEncContext * s, |
| 1052 |
int *mx_ptr, int *my_ptr) |
| 1053 |
{
|
| 1054 |
MVTable *mv; |
| 1055 |
int code, mx, my;
|
| 1056 |
|
| 1057 |
mv = &mv_tables[s->mv_table_index]; |
| 1058 |
|
| 1059 |
code = get_vlc(&s->gb, &mv->vlc); |
| 1060 |
if (code < 0) |
| 1061 |
return -1; |
| 1062 |
if (code == mv->n) {
|
| 1063 |
mx = get_bits(&s->gb, 6);
|
| 1064 |
my = get_bits(&s->gb, 6);
|
| 1065 |
} else {
|
| 1066 |
mx = mv->table_mvx[code]; |
| 1067 |
my = mv->table_mvy[code]; |
| 1068 |
} |
| 1069 |
|
| 1070 |
mx += *mx_ptr - 32;
|
| 1071 |
my += *my_ptr - 32;
|
| 1072 |
/* WARNING : they do not do exactly modulo encoding */
|
| 1073 |
if (mx <= -64) |
| 1074 |
mx += 64;
|
| 1075 |
else if (mx >= 64) |
| 1076 |
mx -= 64;
|
| 1077 |
|
| 1078 |
if (my <= -64) |
| 1079 |
my += 64;
|
| 1080 |
else if (my >= 64) |
| 1081 |
my -= 64;
|
| 1082 |
*mx_ptr = mx; |
| 1083 |
*my_ptr = my; |
| 1084 |
return 0; |
| 1085 |
} |