mpeg12.c
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C
1,844 行
/*
* MPEG1/2 decoder
* Copyright (c) 2000,2001 Fabrice Bellard.
* Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
*
* 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 mpeg12.c
* MPEG1/2 decoder
*/
//#define DEBUG
#include "avcodec.h"
#include "dsputil.h"
#include "mpegvideo.h"
#include "mpeg12.h"
#include "mpeg12data.h"
#include "mpeg12decdata.h"
#include "bytestream.h"
//#undef NDEBUG
//#include <assert.h>
#define DC_VLC_BITS 9
#define MV_VLC_BITS 9
#define MBINCR_VLC_BITS 9
#define MB_PAT_VLC_BITS 9
#define MB_PTYPE_VLC_BITS 6
#define MB_BTYPE_VLC_BITS 6
#define TEX_VLC_BITS 9
static inline int mpeg1_decode_block_inter(MpegEncContext *s,
DCTELEM *block,
int n);
static inline int mpeg1_decode_block_intra(MpegEncContext *s,
DCTELEM *block,
int n);
static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n);
static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
DCTELEM *block,
int n);
static inline int mpeg2_decode_block_intra(MpegEncContext *s,
DCTELEM *block,
int n);
static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s, DCTELEM *block, int n);
static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n);
static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred);
static void exchange_uv(MpegEncContext *s);
extern int XVMC_field_start(MpegEncContext *s, AVCodecContext *avctx);
extern int XVMC_field_end(MpegEncContext *s);
extern void XVMC_pack_pblocks(MpegEncContext *s,int cbp);
extern void XVMC_init_block(MpegEncContext *s);//set s->block
static const enum PixelFormat pixfmt_yuv_420[]= {PIX_FMT_YUV420P,-1};
static const enum PixelFormat pixfmt_yuv_422[]= {PIX_FMT_YUV422P,-1};
static const enum PixelFormat pixfmt_yuv_444[]= {PIX_FMT_YUV444P,-1};
static const enum PixelFormat pixfmt_xvmc_mpg2_420[] = {
PIX_FMT_XVMC_MPEG2_IDCT,
PIX_FMT_XVMC_MPEG2_MC,
-1};
uint8_t ff_mpeg12_static_rl_table_store[2][2][2*MAX_RUN + MAX_LEVEL + 3];
static void init_2d_vlc_rl(RLTable *rl, int use_static)
{
int i;
init_vlc(&rl->vlc, TEX_VLC_BITS, rl->n + 2,
&rl->table_vlc[0][1], 4, 2,
&rl->table_vlc[0][0], 4, 2, use_static);
if(use_static)
rl->rl_vlc[0]= av_mallocz_static(rl->vlc.table_size*sizeof(RL_VLC_ELEM));
else
rl->rl_vlc[0]= av_malloc(rl->vlc.table_size*sizeof(RL_VLC_ELEM));
for(i=0; i<rl->vlc.table_size; i++){
int code= rl->vlc.table[i][0];
int len = rl->vlc.table[i][1];
int level, run;
if(len==0){ // illegal code
run= 65;
level= MAX_LEVEL;
}else if(len<0){ //more bits needed
run= 0;
level= code;
}else{
if(code==rl->n){ //esc
run= 65;
level= 0;
}else if(code==rl->n+1){ //eob
run= 0;
level= 127;
}else{
run= rl->table_run [code] + 1;
level= rl->table_level[code];
}
}
rl->rl_vlc[0][i].len= len;
rl->rl_vlc[0][i].level= level;
rl->rl_vlc[0][i].run= run;
}
}
void ff_mpeg12_common_init(MpegEncContext *s)
{
s->y_dc_scale_table=
s->c_dc_scale_table= mpeg2_dc_scale_table[s->intra_dc_precision];
}
void ff_mpeg1_clean_buffers(MpegEncContext *s){
s->last_dc[0] = 1 << (7 + s->intra_dc_precision);
s->last_dc[1] = s->last_dc[0];
s->last_dc[2] = s->last_dc[0];
memset(s->last_mv, 0, sizeof(s->last_mv));
}
/******************************************/
/* decoding */
static VLC dc_lum_vlc;
static VLC dc_chroma_vlc;
static VLC mv_vlc;
static VLC mbincr_vlc;
static VLC mb_ptype_vlc;
static VLC mb_btype_vlc;
static VLC mb_pat_vlc;
static void init_vlcs(void)
{
static int done = 0;
if (!done) {
done = 1;
init_vlc(&dc_lum_vlc, DC_VLC_BITS, 12,
ff_mpeg12_vlc_dc_lum_bits, 1, 1,
ff_mpeg12_vlc_dc_lum_code, 2, 2, 1);
init_vlc(&dc_chroma_vlc, DC_VLC_BITS, 12,
ff_mpeg12_vlc_dc_chroma_bits, 1, 1,
ff_mpeg12_vlc_dc_chroma_code, 2, 2, 1);
init_vlc(&mv_vlc, MV_VLC_BITS, 17,
&ff_mpeg12_mbMotionVectorTable[0][1], 2, 1,
&ff_mpeg12_mbMotionVectorTable[0][0], 2, 1, 1);
init_vlc(&mbincr_vlc, MBINCR_VLC_BITS, 36,
&ff_mpeg12_mbAddrIncrTable[0][1], 2, 1,
&ff_mpeg12_mbAddrIncrTable[0][0], 2, 1, 1);
init_vlc(&mb_pat_vlc, MB_PAT_VLC_BITS, 64,
&ff_mpeg12_mbPatTable[0][1], 2, 1,
&ff_mpeg12_mbPatTable[0][0], 2, 1, 1);
init_vlc(&mb_ptype_vlc, MB_PTYPE_VLC_BITS, 7,
&table_mb_ptype[0][1], 2, 1,
&table_mb_ptype[0][0], 2, 1, 1);
init_vlc(&mb_btype_vlc, MB_BTYPE_VLC_BITS, 11,
&table_mb_btype[0][1], 2, 1,
&table_mb_btype[0][0], 2, 1, 1);
init_rl(&ff_rl_mpeg1, ff_mpeg12_static_rl_table_store[0]);
init_rl(&ff_rl_mpeg2, ff_mpeg12_static_rl_table_store[1]);
init_2d_vlc_rl(&ff_rl_mpeg1, 1);
init_2d_vlc_rl(&ff_rl_mpeg2, 1);
}
}
static inline int get_dmv(MpegEncContext *s)
{
if(get_bits1(&s->gb))
return 1 - (get_bits1(&s->gb) << 1);
else
return 0;
}
static inline int get_qscale(MpegEncContext *s)
{
int qscale = get_bits(&s->gb, 5);
if (s->q_scale_type) {
return non_linear_qscale[qscale];
} else {
return qscale << 1;
}
}
/* motion type (for mpeg2) */
#define MT_FIELD 1
#define MT_FRAME 2
#define MT_16X8 2
#define MT_DMV 3
static int mpeg_decode_mb(MpegEncContext *s,
DCTELEM block[12][64])
{
int i, j, k, cbp, val, mb_type, motion_type;
const int mb_block_count = 4 + (1<< s->chroma_format);
dprintf(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
assert(s->mb_skipped==0);
if (s->mb_skip_run-- != 0) {
if (s->pict_type == P_TYPE) {
s->mb_skipped = 1;
s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
} else {
int mb_type;
if(s->mb_x)
mb_type= s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1];
else
mb_type= s->current_picture.mb_type[ s->mb_width + (s->mb_y-1)*s->mb_stride - 1]; // FIXME not sure if this is allowed in mpeg at all,
if(IS_INTRA(mb_type))
return -1;
s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]=
mb_type | MB_TYPE_SKIP;
// assert(s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1]&(MB_TYPE_16x16|MB_TYPE_16x8));
if((s->mv[0][0][0]|s->mv[0][0][1]|s->mv[1][0][0]|s->mv[1][0][1])==0)
s->mb_skipped = 1;
}
return 0;
}
switch(s->pict_type) {
default:
case I_TYPE:
if (get_bits1(&s->gb) == 0) {
if (get_bits1(&s->gb) == 0){
av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in I Frame at %d %d\n", s->mb_x, s->mb_y);
return -1;
}
mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
} else {
mb_type = MB_TYPE_INTRA;
}
break;
case P_TYPE:
mb_type = get_vlc2(&s->gb, mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
if (mb_type < 0){
av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
return -1;
}
mb_type = ptype2mb_type[ mb_type ];
break;
case B_TYPE:
mb_type = get_vlc2(&s->gb, mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
if (mb_type < 0){
av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
return -1;
}
mb_type = btype2mb_type[ mb_type ];
break;
}
dprintf(s->avctx, "mb_type=%x\n", mb_type);
// motion_type = 0; /* avoid warning */
if (IS_INTRA(mb_type)) {
s->dsp.clear_blocks(s->block[0]);
if(!s->chroma_y_shift){
s->dsp.clear_blocks(s->block[6]);
}
/* compute dct type */
if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?
!s->frame_pred_frame_dct) {
s->interlaced_dct = get_bits1(&s->gb);
}
if (IS_QUANT(mb_type))
s->qscale = get_qscale(s);
if (s->concealment_motion_vectors) {
/* just parse them */
if (s->picture_structure != PICT_FRAME)
skip_bits1(&s->gb); /* field select */
s->mv[0][0][0]= s->last_mv[0][0][0]= s->last_mv[0][1][0] =
mpeg_decode_motion(s, s->mpeg_f_code[0][0], s->last_mv[0][0][0]);
s->mv[0][0][1]= s->last_mv[0][0][1]= s->last_mv[0][1][1] =
mpeg_decode_motion(s, s->mpeg_f_code[0][1], s->last_mv[0][0][1]);
skip_bits1(&s->gb); /* marker */
}else
memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */
s->mb_intra = 1;
#ifdef HAVE_XVMC
//one 1 we memcpy blocks in xvmcvideo
if(s->avctx->xvmc_acceleration > 1){
XVMC_pack_pblocks(s,-1);//inter are always full blocks
if(s->swap_uv){
exchange_uv(s);
}
}
#endif
if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
if(s->flags2 & CODEC_FLAG2_FAST){
for(i=0;i<6;i++) {
mpeg2_fast_decode_block_intra(s, s->pblocks[i], i);
}
}else{
for(i=0;i<mb_block_count;i++) {
if (mpeg2_decode_block_intra(s, s->pblocks[i], i) < 0)
return -1;
}
}
} else {
for(i=0;i<6;i++) {
if (mpeg1_decode_block_intra(s, s->pblocks[i], i) < 0)
return -1;
}
}
} else {
if (mb_type & MB_TYPE_ZERO_MV){
assert(mb_type & MB_TYPE_CBP);
s->mv_dir = MV_DIR_FORWARD;
if(s->picture_structure == PICT_FRAME){
if(!s->frame_pred_frame_dct)
s->interlaced_dct = get_bits1(&s->gb);
s->mv_type = MV_TYPE_16X16;
}else{
s->mv_type = MV_TYPE_FIELD;
mb_type |= MB_TYPE_INTERLACED;
s->field_select[0][0]= s->picture_structure - 1;
}
if (IS_QUANT(mb_type))
s->qscale = get_qscale(s);
s->last_mv[0][0][0] = 0;
s->last_mv[0][0][1] = 0;
s->last_mv[0][1][0] = 0;
s->last_mv[0][1][1] = 0;
s->mv[0][0][0] = 0;
s->mv[0][0][1] = 0;
}else{
assert(mb_type & MB_TYPE_L0L1);
//FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
/* get additional motion vector type */
if (s->frame_pred_frame_dct)
motion_type = MT_FRAME;
else{
motion_type = get_bits(&s->gb, 2);
if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
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