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ffmpeg/libavcodec/ituh263dec.c
2025-07-03 20:35:32 +02:00

1387 lines
45 KiB
C

/*
* ITU H.263 bitstream decoder
* Copyright (c) 2000,2001 Fabrice Bellard
* H.263+ support.
* Copyright (c) 2001 Juan J. Sierralta P
* 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
* H.263 decoder.
*/
#define UNCHECKED_BITSTREAM_READER 1
#include "config_components.h"
#include "libavutil/attributes.h"
#include "libavutil/imgutils.h"
#include "libavutil/internal.h"
#include "libavutil/mathematics.h"
#include "libavutil/mem_internal.h"
#include "libavutil/thread.h"
#include "avcodec.h"
#include "mpegvideo.h"
#include "h263.h"
#include "h263data.h"
#include "h263dec.h"
#include "mathops.h"
#include "mpegutils.h"
#include "unary.h"
#include "rv10dec.h"
#include "mpeg4video.h"
#include "mpegvideodata.h"
#include "mpegvideodec.h"
#include "mpeg4videodec.h"
#include "mpeg4videodefs.h"
// The defines below define the number of bits that are read at once for
// reading vlc values. Changing these may improve speed and data cache needs
// be aware though that decreasing them may need the number of stages that is
// passed to get_vlc* to be increased.
#define H263_MBTYPE_B_VLC_BITS 6
#define CBPC_B_VLC_BITS 3
static const int16_t h263_mb_type_b_map[15]= {
MB_TYPE_DIRECT2 | MB_TYPE_BIDIR_MV,
MB_TYPE_DIRECT2 | MB_TYPE_BIDIR_MV | MB_TYPE_CBP,
MB_TYPE_DIRECT2 | MB_TYPE_BIDIR_MV | MB_TYPE_CBP | MB_TYPE_QUANT,
MB_TYPE_FORWARD_MV | MB_TYPE_16x16,
MB_TYPE_FORWARD_MV | MB_TYPE_CBP | MB_TYPE_16x16,
MB_TYPE_FORWARD_MV | MB_TYPE_CBP | MB_TYPE_QUANT | MB_TYPE_16x16,
MB_TYPE_BACKWARD_MV | MB_TYPE_16x16,
MB_TYPE_BACKWARD_MV | MB_TYPE_CBP | MB_TYPE_16x16,
MB_TYPE_BACKWARD_MV | MB_TYPE_CBP | MB_TYPE_QUANT | MB_TYPE_16x16,
MB_TYPE_BIDIR_MV | MB_TYPE_16x16,
MB_TYPE_BIDIR_MV | MB_TYPE_CBP | MB_TYPE_16x16,
MB_TYPE_BIDIR_MV | MB_TYPE_CBP | MB_TYPE_QUANT | MB_TYPE_16x16,
0, //stuffing
MB_TYPE_INTRA4x4 | MB_TYPE_CBP,
MB_TYPE_INTRA4x4 | MB_TYPE_CBP | MB_TYPE_QUANT,
};
void ff_h263_show_pict_info(H263DecContext *const h, int h263_plus)
{
if (h->c.avctx->debug&FF_DEBUG_PICT_INFO) {
av_log(h->c.avctx, AV_LOG_DEBUG, "qp:%d %c size:%d rnd:%d%s%s%s%s%s%s%s%s%s %d/%d\n",
h->c.qscale, av_get_picture_type_char(h->c.pict_type),
h->gb.size_in_bits, 1-h->c.no_rounding,
h->c.obmc ? " AP" : "",
h->umvplus ? " UMV" : "",
h->h263_long_vectors ? " LONG" : "",
h263_plus ? " +" : "",
h->c.h263_aic ? " AIC" : "",
h->alt_inter_vlc ? " AIV" : "",
h->modified_quant ? " MQ" : "",
h->loop_filter ? " LOOP" : "",
h->h263_slice_structured ? " SS" : "",
h->c.avctx->framerate.num, h->c.avctx->framerate.den);
}
}
/***********************************************/
/* decoding */
VLCElem ff_h263_intra_MCBPC_vlc[72];
VLCElem ff_h263_inter_MCBPC_vlc[198];
VLCElem ff_h263_cbpy_vlc[64];
VLCElem ff_h263_mv_vlc[538];
static VLCElem h263_mbtype_b_vlc[80];
static VLCElem cbpc_b_vlc[8];
/* init vlcs */
static av_cold void h263_decode_init_vlc(void)
{
VLC_INIT_STATIC_TABLE(ff_h263_intra_MCBPC_vlc, INTRA_MCBPC_VLC_BITS, 9,
ff_h263_intra_MCBPC_bits, 1, 1,
ff_h263_intra_MCBPC_code, 1, 1, 0);
VLC_INIT_STATIC_TABLE(ff_h263_inter_MCBPC_vlc, INTER_MCBPC_VLC_BITS, 28,
ff_h263_inter_MCBPC_bits, 1, 1,
ff_h263_inter_MCBPC_code, 1, 1, 0);
VLC_INIT_STATIC_TABLE(ff_h263_cbpy_vlc, CBPY_VLC_BITS, 16,
&ff_h263_cbpy_tab[0][1], 2, 1,
&ff_h263_cbpy_tab[0][0], 2, 1, 0);
VLC_INIT_STATIC_TABLE(ff_h263_mv_vlc, H263_MV_VLC_BITS, 33,
&ff_mvtab[0][1], 2, 1,
&ff_mvtab[0][0], 2, 1, 0);
VLC_INIT_RL(ff_h263_rl_inter, 554);
INIT_FIRST_VLC_RL(ff_rl_intra_aic, 554);
VLC_INIT_STATIC_SPARSE_TABLE(h263_mbtype_b_vlc, H263_MBTYPE_B_VLC_BITS, 15,
&ff_h263_mbtype_b_tab[0][1], 2, 1,
&ff_h263_mbtype_b_tab[0][0], 2, 1,
h263_mb_type_b_map, 2, 2, 0);
VLC_INIT_STATIC_TABLE(cbpc_b_vlc, CBPC_B_VLC_BITS, 4,
&ff_cbpc_b_tab[0][1], 2, 1,
&ff_cbpc_b_tab[0][0], 2, 1, 0);
}
av_cold void ff_h263_decode_init_vlc(void)
{
static AVOnce init_static_once = AV_ONCE_INIT;
ff_thread_once(&init_static_once, h263_decode_init_vlc);
}
int ff_h263_decode_mba(H263DecContext *const h)
{
int i, mb_pos;
for (i = 0; i < 6; i++)
if (h->c.mb_num - 1 <= ff_mba_max[i])
break;
mb_pos = get_bits(&h->gb, ff_mba_length[i]);
h->c.mb_x = mb_pos % h->c.mb_width;
h->c.mb_y = mb_pos / h->c.mb_width;
return mb_pos;
}
/**
* Decode the group of blocks header or slice header.
* @return <0 if an error occurred
*/
static int h263_decode_gob_header(H263DecContext *const h)
{
unsigned int val, gob_number;
int left;
/* Check for GOB Start Code */
val = show_bits(&h->gb, 16);
if(val)
return -1;
/* We have a GBSC probably with GSTUFF */
skip_bits(&h->gb, 16); /* Drop the zeros */
left = get_bits_left(&h->gb);
left = FFMIN(left, 32);
//MN: we must check the bits left or we might end in an infinite loop (or segfault)
for(;left>13; left--){
if (get_bits1(&h->gb))
break; /* Seek the '1' bit */
}
if(left<=13)
return -1;
if (h->h263_slice_structured) {
if (check_marker(h->c.avctx, &h->gb, "before MBA")==0)
return -1;
ff_h263_decode_mba(h);
if (h->c.mb_num > 1583)
if (check_marker(h->c.avctx, &h->gb, "after MBA")==0)
return -1;
h->c.qscale = get_bits(&h->gb, 5); /* SQUANT */
if (check_marker(h->c.avctx, &h->gb, "after SQUANT")==0)
return -1;
skip_bits(&h->gb, 2); /* GFID */
}else{
gob_number = get_bits(&h->gb, 5); /* GN */
h->c.mb_x = 0;
h->c.mb_y = h->gob_index* gob_number;
skip_bits(&h->gb, 2); /* GFID */
h->c.qscale = get_bits(&h->gb, 5); /* GQUANT */
}
if (h->c.mb_y >= h->c.mb_height)
return -1;
if (h->c.qscale==0)
return -1;
return 0;
}
/**
* Decode the group of blocks / video packet header / slice header (MPEG-4 Studio).
* @return bit position of the resync_marker, or <0 if none was found
*/
int ff_h263_resync(H263DecContext *const h)
{
int left, pos, ret;
/* In MPEG-4 studio mode look for a new slice startcode
* and decode slice header */
if (h->c.codec_id==AV_CODEC_ID_MPEG4 && h->c.studio_profile) {
align_get_bits(&h->gb);
while (get_bits_left(&h->gb) >= 32 && show_bits_long(&h->gb, 32) != SLICE_STARTCODE) {
get_bits(&h->gb, 8);
}
if (get_bits_left(&h->gb) >= 32 && show_bits_long(&h->gb, 32) == SLICE_STARTCODE)
return get_bits_count(&h->gb);
else
return -1;
}
if (h->c.codec_id==AV_CODEC_ID_MPEG4){
skip_bits1(&h->gb);
align_get_bits(&h->gb);
}
if (show_bits(&h->gb, 16) ==0) {
pos = get_bits_count(&h->gb);
if(CONFIG_MPEG4_DECODER && h->c.codec_id==AV_CODEC_ID_MPEG4)
ret = ff_mpeg4_decode_video_packet_header(h);
else
ret = h263_decode_gob_header(h);
if(ret>=0)
return pos;
}
//OK, it's not where it is supposed to be ...
h->gb = h->last_resync_gb;
align_get_bits(&h->gb);
left = get_bits_left(&h->gb);
for(;left>16+1+5+5; left-=8){
if (show_bits(&h->gb, 16) == 0){
GetBitContext bak = h->gb;
pos = get_bits_count(&h->gb);
if(CONFIG_MPEG4_DECODER && h->c.codec_id==AV_CODEC_ID_MPEG4)
ret = ff_mpeg4_decode_video_packet_header(h);
else
ret = h263_decode_gob_header(h);
if(ret>=0)
return pos;
h->gb = bak;
}
skip_bits(&h->gb, 8);
}
return -1;
}
int ff_h263_decode_motion(H263DecContext *const h, int pred, int f_code)
{
int code, val, sign, shift;
code = get_vlc2(&h->gb, ff_h263_mv_vlc, H263_MV_VLC_BITS, 2);
if (code == 0)
return pred;
if (code < 0)
return 0xffff;
sign = get_bits1(&h->gb);
shift = f_code - 1;
val = code;
if (shift) {
val = (val - 1) << shift;
val |= get_bits(&h->gb, shift);
val++;
}
if (sign)
val = -val;
val += pred;
/* modulo decoding */
if (!h->h263_long_vectors) {
val = sign_extend(val, 5 + f_code);
} else {
/* horrible H.263 long vector mode */
if (pred < -31 && val < -63)
val += 64;
if (pred > 32 && val > 63)
val -= 64;
}
return val;
}
/* Decode RVLC of H.263+ UMV */
static int h263p_decode_umotion(H263DecContext *const h, int pred)
{
int code = 0, sign;
if (get_bits1(&h->gb)) /* Motion difference = 0 */
return pred;
code = 2 + get_bits1(&h->gb);
while (get_bits1(&h->gb))
{
code <<= 1;
code += get_bits1(&h->gb);
if (code >= 32768) {
avpriv_request_sample(h->c.avctx, "Huge DMV");
return 0xffff;
}
}
sign = code & 1;
code >>= 1;
code = (sign) ? (pred - code) : (pred + code);
ff_tlog(h->c.avctx,"H.263+ UMV Motion = %d\n", code);
return code;
}
/**
* read the next MVs for OBMC. yes this is an ugly hack, feel free to send a patch :)
*/
static void preview_obmc(H263DecContext *const h)
{
GetBitContext gb = h->gb;
int cbpc, i, pred_x, pred_y, mx, my;
int16_t *mot_val;
const int xy = h->c.mb_x + 1 + h->c.mb_y * h->c.mb_stride;
const int stride = h->c.b8_stride * 2;
for(i=0; i<4; i++)
h->c.block_index[i] += 2;
for(i=4; i<6; i++)
h->c.block_index[i] += 1;
h->c.mb_x++;
av_assert2(h->c.pict_type == AV_PICTURE_TYPE_P);
do{
if (get_bits1(&h->gb)) {
/* skip mb */
mot_val = h->c.cur_pic.motion_val[0][h->c.block_index[0]];
mot_val[0 ]= mot_val[2 ]=
mot_val[0+stride]= mot_val[2+stride]= 0;
mot_val[1 ]= mot_val[3 ]=
mot_val[1+stride]= mot_val[3+stride]= 0;
h->c.cur_pic.mb_type[xy] = MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_FORWARD_MV;
goto end;
}
cbpc = get_vlc2(&h->gb, ff_h263_inter_MCBPC_vlc, INTER_MCBPC_VLC_BITS, 2);
}while(cbpc == 20);
if(cbpc & 4){
h->c.cur_pic.mb_type[xy] = MB_TYPE_INTRA;
}else{
get_vlc2(&h->gb, ff_h263_cbpy_vlc, CBPY_VLC_BITS, 1);
if (cbpc & 8) {
skip_bits(&h->gb, h->modified_quant ? (get_bits1(&h->gb) ? 1 : 5) : 2);
}
if ((cbpc & 16) == 0) {
h->c.cur_pic.mb_type[xy] = MB_TYPE_16x16 | MB_TYPE_FORWARD_MV;
/* 16x16 motion prediction */
mot_val= ff_h263_pred_motion(&h->c, 0, 0, &pred_x, &pred_y);
if (h->umvplus)
mx = h263p_decode_umotion(h, pred_x);
else
mx = ff_h263_decode_motion(h, pred_x, 1);
if (h->umvplus)
my = h263p_decode_umotion(h, pred_y);
else
my = ff_h263_decode_motion(h, pred_y, 1);
mot_val[0 ]= mot_val[2 ]=
mot_val[0+stride]= mot_val[2+stride]= mx;
mot_val[1 ]= mot_val[3 ]=
mot_val[1+stride]= mot_val[3+stride]= my;
} else {
h->c.cur_pic.mb_type[xy] = MB_TYPE_8x8 | MB_TYPE_FORWARD_MV;
for(i=0;i<4;i++) {
mot_val = ff_h263_pred_motion(&h->c, i, 0, &pred_x, &pred_y);
if (h->umvplus)
mx = h263p_decode_umotion(h, pred_x);
else
mx = ff_h263_decode_motion(h, pred_x, 1);
if (h->umvplus)
my = h263p_decode_umotion(h, pred_y);
else
my = ff_h263_decode_motion(h, pred_y, 1);
if (h->umvplus && (mx - pred_x) == 1 && (my - pred_y) == 1)
skip_bits1(&h->gb); /* Bit stuffing to prevent PSC */
mot_val[0] = mx;
mot_val[1] = my;
}
}
}
end:
for(i=0; i<4; i++)
h->c.block_index[i] -= 2;
for(i=4; i<6; i++)
h->c.block_index[i] -= 1;
h->c.mb_x--;
h->gb = gb;
}
static void h263_decode_dquant(H263DecContext *const h)
{
static const int8_t quant_tab[4] = { -1, -2, 1, 2 };
int qscale;
if (h->modified_quant) {
if (get_bits1(&h->gb))
qscale = ff_modified_quant_tab[get_bits1(&h->gb)][h->c.qscale];
else
qscale = get_bits(&h->gb, 5);
}else
qscale = h->c.qscale + quant_tab[get_bits(&h->gb, 2)];
ff_set_qscale(&h->c, qscale);
}
static void h263_pred_acdc(MpegEncContext * s, int16_t *block, int n)
{
int wrap, a, c, pred_dc, scale;
const int xy = s->block_index[n];
int16_t *const dc_val = s->dc_val + xy;
int16_t *const ac_val = (s->ac_val + xy)[0];
/* find prediction */
if (n < 4) {
wrap = s->b8_stride;
scale = s->y_dc_scale;
} else {
wrap = s->mb_stride;
scale = s->c_dc_scale;
}
/* B C
* A X
*/
a = dc_val[-1];
c = dc_val[-wrap];
/* No prediction outside GOB boundary */
if (s->first_slice_line && n != 3) {
if (n != 2) c= 1024;
if (n != 1 && s->mb_x == s->resync_mb_x) a= 1024;
}
if (s->ac_pred) {
pred_dc = 1024;
if (s->h263_aic_dir) {
/* left prediction */
if (a != 1024) {
int16_t *const ac_val2 = ac_val - 16;
for (int i = 1; i < 8; i++) {
block[s->idsp.idct_permutation[i << 3]] += ac_val2[i];
}
pred_dc = a;
}
} else {
/* top prediction */
if (c != 1024) {
int16_t *const ac_val2 = ac_val - 16 * wrap;
for (int i = 1; i < 8; i++) {
block[s->idsp.idct_permutation[i]] += ac_val2[i + 8];
}
pred_dc = c;
}
}
} else {
/* just DC prediction */
if (a != 1024 && c != 1024)
pred_dc = (a + c) >> 1;
else if (a != 1024)
pred_dc = a;
else
pred_dc = c;
}
/* we assume pred is positive */
block[0] = block[0] * scale + pred_dc;
if (block[0] < 0)
block[0] = 0;
else
block[0] |= 1;
/* Update AC/DC tables */
*dc_val = block[0];
/* left copy */
for (int i = 1; i < 8; i++)
ac_val[i] = block[s->idsp.idct_permutation[i << 3]];
/* top copy */
for (int i = 1; i < 8; i++)
ac_val[8 + i] = block[s->idsp.idct_permutation[i]];
}
static int h263_decode_block(H263DecContext *const h, int16_t block[64],
int n, int coded)
{
int level, i, j, run;
const RLTable *rl = &ff_h263_rl_inter;
const uint8_t *scan_table;
GetBitContext gb = h->gb;
scan_table = h->c.intra_scantable.permutated;
if (h->c.h263_aic && h->c.mb_intra) {
i = 0;
if (!coded)
goto not_coded;
rl = &ff_rl_intra_aic;
if (h->c.ac_pred) {
if (h->c.h263_aic_dir)
scan_table = h->c.permutated_intra_v_scantable; /* left */
else
scan_table = h->c.permutated_intra_h_scantable; /* top */
}
} else if (h->c.mb_intra) {
/* DC coef */
if (CONFIG_RV10_DECODER && h->c.codec_id == AV_CODEC_ID_RV10) {
if (h->rv10_version == 3 && h->c.pict_type == AV_PICTURE_TYPE_I) {
int component = (n <= 3 ? 0 : n - 4 + 1);
level = h->c.last_dc[component];
if (h->rv10_first_dc_coded[component]) {
int diff = ff_rv_decode_dc(h, n);
if (diff < 0)
return -1;
level += diff;
level = level & 0xff; /* handle wrap round */
h->c.last_dc[component] = level;
} else {
h->rv10_first_dc_coded[component] = 1;
}
} else {
level = get_bits(&h->gb, 8);
if (level == 255)
level = 128;
}
}else{
level = get_bits(&h->gb, 8);
if((level&0x7F) == 0){
av_log(h->c.avctx, AV_LOG_ERROR, "illegal dc %d at %d %d\n",
level, h->c.mb_x, h->c.mb_y);
if (h->c.avctx->err_recognition & (AV_EF_BITSTREAM|AV_EF_COMPLIANT))
return -1;
}
if (level == 255)
level = 128;
}
block[0] = level;
i = 1;
} else {
i = 0;
}
if (!coded) {
h->c.block_last_index[n] = i - 1;
return 0;
}
retry:
{
OPEN_READER(re, &h->gb);
i--; // offset by -1 to allow direct indexing of scan_table
for(;;) {
UPDATE_CACHE(re, &h->gb);
GET_RL_VLC(level, run, re, &h->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
if (run == 66) {
if (level){
CLOSE_READER(re, &h->gb);
av_log(h->c.avctx, AV_LOG_ERROR, "illegal ac vlc code at %dx%d\n",
h->c.mb_x, h->c.mb_y);
return -1;
}
/* escape */
if (CONFIG_FLV_DECODER && h->flv) {
int is11 = SHOW_UBITS(re, &h->gb, 1);
SKIP_CACHE(re, &h->gb, 1);
run = SHOW_UBITS(re, &h->gb, 7) + 1;
if (is11) {
SKIP_COUNTER(re, &h->gb, 1 + 7);
UPDATE_CACHE(re, &h->gb);
level = SHOW_SBITS(re, &h->gb, 11);
SKIP_COUNTER(re, &h->gb, 11);
} else {
SKIP_CACHE(re, &h->gb, 7);
level = SHOW_SBITS(re, &h->gb, 7);
SKIP_COUNTER(re, &h->gb, 1 + 7 + 7);
}
} else {
run = SHOW_UBITS(re, &h->gb, 7) + 1;
SKIP_CACHE(re, &h->gb, 7);
level = (int8_t)SHOW_UBITS(re, &h->gb, 8);
SKIP_COUNTER(re, &h->gb, 7 + 8);
if(level == -128){
UPDATE_CACHE(re, &h->gb);
if (h->c.codec_id == AV_CODEC_ID_RV10) {
/* XXX: should patch encoder too */
level = SHOW_SBITS(re, &h->gb, 12);
SKIP_COUNTER(re, &h->gb, 12);
}else{
level = SHOW_UBITS(re, &h->gb, 5);
SKIP_CACHE(re, &h->gb, 5);
level |= SHOW_SBITS(re, &h->gb, 6) * (1<<5);
SKIP_COUNTER(re, &h->gb, 5 + 6);
}
}
}
} else {
if (SHOW_UBITS(re, &h->gb, 1))
level = -level;
SKIP_COUNTER(re, &h->gb, 1);
}
i += run;
if (i >= 64){
CLOSE_READER(re, &h->gb);
// redo update without last flag, revert -1 offset
i = i - run + ((run-1)&63) + 1;
if (i < 64) {
// only last marker, no overrun
block[scan_table[i]] = level;
break;
}
if(h->alt_inter_vlc && rl == &ff_h263_rl_inter && !h->c.mb_intra){
//Looks like a hack but no, it's the way it is supposed to work ...
rl = &ff_rl_intra_aic;
i = 0;
h->gb = gb;
h->c.bdsp.clear_block(block);
goto retry;
}
av_log(h->c.avctx, AV_LOG_ERROR, "run overflow at %dx%d i:%d\n",
h->c.mb_x, h->c.mb_y, h->c.mb_intra);
return -1;
}
j = scan_table[i];
block[j] = level;
}
}
if (h->c.mb_intra && h->c.h263_aic) {
not_coded:
h263_pred_acdc(&h->c, block, n);
}
h->c.block_last_index[n] = i;
return 0;
}
static int h263_skip_b_part(H263DecContext *const h, int cbp)
{
LOCAL_ALIGNED_32(int16_t, dblock, [64]);
int i, mbi;
int bli[6];
/* we have to set h->c.mb_intra to zero to decode B-part of PB-frame correctly
* but real value should be restored in order to be used later (in OBMC condition)
*/
mbi = h->c.mb_intra;
memcpy(bli, h->c.block_last_index, sizeof(bli));
h->c.mb_intra = 0;
for (i = 0; i < 6; i++) {
if (h263_decode_block(h, dblock, i, cbp&32) < 0)
return -1;
cbp+=cbp;
}
h->c.mb_intra = mbi;
memcpy(h->c.block_last_index, bli, sizeof(bli));
return 0;
}
static int h263_get_modb(GetBitContext *gb, int pb_frame, int *cbpb)
{
int c, mv = 1;
if (pb_frame < 3) { // h.263 Annex G and i263 PB-frame
c = get_bits1(gb);
if (pb_frame == 2 && c)
mv = !get_bits1(gb);
} else { // h.263 Annex M improved PB-frame
mv = get_unary(gb, 0, 4) + 1;
c = mv & 1;
mv = !!(mv & 2);
}
if(c)
*cbpb = get_bits(gb, 6);
return mv;
}
#define tab_size ((signed)FF_ARRAY_ELEMS(s->direct_scale_mv[0]))
#define tab_bias (tab_size / 2)
static inline void set_one_direct_mv(MpegEncContext *s, const MPVPicture *p, int i)
{
int xy = s->block_index[i];
uint16_t time_pp = s->pp_time;
uint16_t time_pb = s->pb_time;
int p_mx, p_my;
p_mx = p->motion_val[0][xy][0];
if ((unsigned)(p_mx + tab_bias) < tab_size) {
s->mv[0][i][0] = s->direct_scale_mv[0][p_mx + tab_bias];
s->mv[1][i][0] = s->direct_scale_mv[1][p_mx + tab_bias];
} else {
s->mv[0][i][0] = p_mx * time_pb / time_pp;
s->mv[1][i][0] = p_mx * (time_pb - time_pp) / time_pp;
}
p_my = p->motion_val[0][xy][1];
if ((unsigned)(p_my + tab_bias) < tab_size) {
s->mv[0][i][1] = s->direct_scale_mv[0][p_my + tab_bias];
s->mv[1][i][1] = s->direct_scale_mv[1][p_my + tab_bias];
} else {
s->mv[0][i][1] = p_my * time_pb / time_pp;
s->mv[1][i][1] = p_my * (time_pb - time_pp) / time_pp;
}
}
/**
* @return the mb_type
*/
static int set_direct_mv(MpegEncContext *s)
{
const int mb_index = s->mb_x + s->mb_y * s->mb_stride;
const MPVPicture *p = s->next_pic.ptr;
int colocated_mb_type = p->mb_type[mb_index];
int i;
if (s->codec_tag == AV_RL32("U263") && p->f->pict_type == AV_PICTURE_TYPE_I) {
p = s->last_pic.ptr;
colocated_mb_type = p->mb_type[mb_index];
}
if (IS_8X8(colocated_mb_type)) {
s->mv_type = MV_TYPE_8X8;
for (i = 0; i < 4; i++)
set_one_direct_mv(s, p, i);
return MB_TYPE_DIRECT2 | MB_TYPE_8x8 | MB_TYPE_BIDIR_MV;
} else {
set_one_direct_mv(s, p, 0);
s->mv[0][1][0] =
s->mv[0][2][0] =
s->mv[0][3][0] = s->mv[0][0][0];
s->mv[0][1][1] =
s->mv[0][2][1] =
s->mv[0][3][1] = s->mv[0][0][1];
s->mv[1][1][0] =
s->mv[1][2][0] =
s->mv[1][3][0] = s->mv[1][0][0];
s->mv[1][1][1] =
s->mv[1][2][1] =
s->mv[1][3][1] = s->mv[1][0][1];
s->mv_type = MV_TYPE_8X8;
// Note see prev line
return MB_TYPE_DIRECT2 | MB_TYPE_16x16 | MB_TYPE_BIDIR_MV;
}
}
int ff_h263_decode_mb(H263DecContext *const h)
{
int cbpc, cbpy, i, cbp, pred_x, pred_y, mx, my, dquant;
int16_t *mot_val;
const int xy = h->c.mb_x + h->c.mb_y * h->c.mb_stride;
int cbpb = 0, pb_mv_count = 0;
av_assert2(!h->c.h263_pred);
if (h->c.pict_type == AV_PICTURE_TYPE_P) {
do{
if (get_bits1(&h->gb)) {
/* skip mb */
h->c.mb_intra = 0;
for(i=0;i<6;i++)
h->c.block_last_index[i] = -1;
h->c.mv_dir = MV_DIR_FORWARD;
h->c.mv_type = MV_TYPE_16X16;
h->c.cur_pic.mb_type[xy] = MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_FORWARD_MV;
h->c.mv[0][0][0] = 0;
h->c.mv[0][0][1] = 0;
h->c.mb_skipped = !(h->c.obmc | h->loop_filter);
goto end;
}
cbpc = get_vlc2(&h->gb, ff_h263_inter_MCBPC_vlc, INTER_MCBPC_VLC_BITS, 2);
if (cbpc < 0){
av_log(h->c.avctx, AV_LOG_ERROR, "cbpc damaged at %d %d\n",
h->c.mb_x, h->c.mb_y);
return SLICE_ERROR;
}
}while(cbpc == 20);
h->c.bdsp.clear_blocks(h->block[0]);
dquant = cbpc & 8;
h->c.mb_intra = ((cbpc & 4) != 0);
if (h->c.mb_intra)
goto intra;
if (h->pb_frame && get_bits1(&h->gb))
pb_mv_count = h263_get_modb(&h->gb, h->pb_frame, &cbpb);
cbpy = get_vlc2(&h->gb, ff_h263_cbpy_vlc, CBPY_VLC_BITS, 1);
if (cbpy < 0) {
av_log(h->c.avctx, AV_LOG_ERROR, "cbpy damaged at %d %d\n",
h->c.mb_x, h->c.mb_y);
return SLICE_ERROR;
}
if (!h->alt_inter_vlc|| (cbpc & 3)!=3)
cbpy ^= 0xF;
cbp = (cbpc & 3) | (cbpy << 2);
if (dquant) {
h263_decode_dquant(h);
}
h->c.mv_dir = MV_DIR_FORWARD;
if ((cbpc & 16) == 0) {
h->c.cur_pic.mb_type[xy] = MB_TYPE_16x16 | MB_TYPE_FORWARD_MV;
/* 16x16 motion prediction */
h->c.mv_type = MV_TYPE_16X16;
ff_h263_pred_motion(&h->c, 0, 0, &pred_x, &pred_y);
if (h->umvplus)
mx = h263p_decode_umotion(h, pred_x);
else
mx = ff_h263_decode_motion(h, pred_x, 1);
if (mx >= 0xffff)
return SLICE_ERROR;
if (h->umvplus)
my = h263p_decode_umotion(h, pred_y);
else
my = ff_h263_decode_motion(h, pred_y, 1);
if (my >= 0xffff)
return SLICE_ERROR;
h->c.mv[0][0][0] = mx;
h->c.mv[0][0][1] = my;
if (h->umvplus && (mx - pred_x) == 1 && (my - pred_y) == 1)
skip_bits1(&h->gb); /* Bit stuffing to prevent PSC */
} else {
h->c.cur_pic.mb_type[xy] = MB_TYPE_8x8 | MB_TYPE_FORWARD_MV;
h->c.mv_type = MV_TYPE_8X8;
for(i=0;i<4;i++) {
mot_val = ff_h263_pred_motion(&h->c, i, 0, &pred_x, &pred_y);
if (h->umvplus)
mx = h263p_decode_umotion(h, pred_x);
else
mx = ff_h263_decode_motion(h, pred_x, 1);
if (mx >= 0xffff)
return SLICE_ERROR;
if (h->umvplus)
my = h263p_decode_umotion(h, pred_y);
else
my = ff_h263_decode_motion(h, pred_y, 1);
if (my >= 0xffff)
return SLICE_ERROR;
h->c.mv[0][i][0] = mx;
h->c.mv[0][i][1] = my;
if (h->umvplus && (mx - pred_x) == 1 && (my - pred_y) == 1)
skip_bits1(&h->gb); /* Bit stuffing to prevent PSC */
mot_val[0] = mx;
mot_val[1] = my;
}
}
} else if (h->c.pict_type==AV_PICTURE_TYPE_B) {
int mb_type;
const int stride = h->c.b8_stride;
int16_t *mot_val0 = h->c.cur_pic.motion_val[0][2 * (h->c.mb_x + h->c.mb_y * stride)];
int16_t *mot_val1 = h->c.cur_pic.motion_val[1][2 * (h->c.mb_x + h->c.mb_y * stride)];
// const int mv_xy = h->c.mb_x + 1 + h->c.mb_y * h->c.mb_stride;
//FIXME ugly
mot_val0[0 ]= mot_val0[2 ]= mot_val0[0+2*stride]= mot_val0[2+2*stride]=
mot_val0[1 ]= mot_val0[3 ]= mot_val0[1+2*stride]= mot_val0[3+2*stride]=
mot_val1[0 ]= mot_val1[2 ]= mot_val1[0+2*stride]= mot_val1[2+2*stride]=
mot_val1[1 ]= mot_val1[3 ]= mot_val1[1+2*stride]= mot_val1[3+2*stride]= 0;
do{
mb_type = get_vlc2(&h->gb, h263_mbtype_b_vlc,
H263_MBTYPE_B_VLC_BITS, 2);
if (mb_type < 0){
av_log(h->c.avctx, AV_LOG_ERROR, "b mb_type damaged at %d %d\n",
h->c.mb_x, h->c.mb_y);
return SLICE_ERROR;
}
}while(!mb_type);
h->c.mb_intra = IS_INTRA(mb_type);
if(HAS_CBP(mb_type)){
h->c.bdsp.clear_blocks(h->block[0]);
cbpc = get_vlc2(&h->gb, cbpc_b_vlc, CBPC_B_VLC_BITS, 1);
if (h->c.mb_intra) {
dquant = IS_QUANT(mb_type);
goto intra;
}
cbpy = get_vlc2(&h->gb, ff_h263_cbpy_vlc, CBPY_VLC_BITS, 1);
if (cbpy < 0){
av_log(h->c.avctx, AV_LOG_ERROR, "b cbpy damaged at %d %d\n",
h->c.mb_x, h->c.mb_y);
return SLICE_ERROR;
}
if (!h->alt_inter_vlc || (cbpc & 3)!=3)
cbpy ^= 0xF;
cbp = (cbpc & 3) | (cbpy << 2);
}else
cbp=0;
av_assert2(!h->c.mb_intra);
if(IS_QUANT(mb_type)){
h263_decode_dquant(h);
}
if(IS_DIRECT(mb_type)){
h->c.mv_dir = MV_DIR_FORWARD | MV_DIR_BACKWARD | MV_DIRECT;
mb_type |= set_direct_mv(&h->c);
}else{
h->c.mv_dir = 0;
h->c.mv_type = MV_TYPE_16X16;
//FIXME UMV
if (HAS_FORWARD_MV(mb_type)) {
int16_t *mot_val = ff_h263_pred_motion(&h->c, 0, 0, &pred_x, &pred_y);
h->c.mv_dir = MV_DIR_FORWARD;
if (h->umvplus)
mx = h263p_decode_umotion(h, pred_x);
else
mx = ff_h263_decode_motion(h, pred_x, 1);
if (mx >= 0xffff)
return SLICE_ERROR;
if (h->umvplus)
my = h263p_decode_umotion(h, pred_y);
else
my = ff_h263_decode_motion(h, pred_y, 1);
if (my >= 0xffff)
return SLICE_ERROR;
if (h->umvplus && (mx - pred_x) == 1 && (my - pred_y) == 1)
skip_bits1(&h->gb); /* Bit stuffing to prevent PSC */
h->c.mv[0][0][0] = mx;
h->c.mv[0][0][1] = my;
mot_val[0 ]= mot_val[2 ]= mot_val[0+2*stride]= mot_val[2+2*stride]= mx;
mot_val[1 ]= mot_val[3 ]= mot_val[1+2*stride]= mot_val[3+2*stride]= my;
}
if (HAS_BACKWARD_MV(mb_type)) {
int16_t *mot_val = ff_h263_pred_motion(&h->c, 0, 1, &pred_x, &pred_y);
h->c.mv_dir |= MV_DIR_BACKWARD;
if (h->umvplus)
mx = h263p_decode_umotion(h, pred_x);
else
mx = ff_h263_decode_motion(h, pred_x, 1);
if (mx >= 0xffff)
return SLICE_ERROR;
if (h->umvplus)
my = h263p_decode_umotion(h, pred_y);
else
my = ff_h263_decode_motion(h, pred_y, 1);
if (my >= 0xffff)
return SLICE_ERROR;
if (h->umvplus && (mx - pred_x) == 1 && (my - pred_y) == 1)
skip_bits1(&h->gb); /* Bit stuffing to prevent PSC */
h->c.mv[1][0][0] = mx;
h->c.mv[1][0][1] = my;
mot_val[0 ]= mot_val[2 ]= mot_val[0+2*stride]= mot_val[2+2*stride]= mx;
mot_val[1 ]= mot_val[3 ]= mot_val[1+2*stride]= mot_val[3+2*stride]= my;
}
}
h->c.cur_pic.mb_type[xy] = mb_type;
} else { /* I-Frame */
do{
cbpc = get_vlc2(&h->gb, ff_h263_intra_MCBPC_vlc, INTRA_MCBPC_VLC_BITS, 2);
if (cbpc < 0){
av_log(h->c.avctx, AV_LOG_ERROR, "I cbpc damaged at %d %d\n",
h->c.mb_x, h->c.mb_y);
return SLICE_ERROR;
}
}while(cbpc == 8);
h->c.bdsp.clear_blocks(h->block[0]);
dquant = cbpc & 4;
h->c.mb_intra = 1;
intra:
h->c.cur_pic.mb_type[xy] = MB_TYPE_INTRA;
if (h->c.h263_aic) {
h->c.ac_pred = get_bits1(&h->gb);
if (h->c.ac_pred) {
h->c.cur_pic.mb_type[xy] = MB_TYPE_INTRA | MB_TYPE_ACPRED;
h->c.h263_aic_dir = get_bits1(&h->gb);
}
}else
h->c.ac_pred = 0;
if (h->pb_frame && get_bits1(&h->gb))
pb_mv_count = h263_get_modb(&h->gb, h->pb_frame, &cbpb);
cbpy = get_vlc2(&h->gb, ff_h263_cbpy_vlc, CBPY_VLC_BITS, 1);
if(cbpy<0){
av_log(h->c.avctx, AV_LOG_ERROR, "I cbpy damaged at %d %d\n",
h->c.mb_x, h->c.mb_y);
return SLICE_ERROR;
}
cbp = (cbpc & 3) | (cbpy << 2);
if (dquant) {
h263_decode_dquant(h);
}
pb_mv_count += !!h->pb_frame;
}
while(pb_mv_count--){
ff_h263_decode_motion(h, 0, 1);
ff_h263_decode_motion(h, 0, 1);
}
/* decode each block */
for (i = 0; i < 6; i++) {
if (h263_decode_block(h, h->block[i], i, cbp&32) < 0)
return -1;
cbp+=cbp;
}
if (h->pb_frame && h263_skip_b_part(h, cbpb) < 0)
return -1;
if (h->c.obmc && !h->c.mb_intra) {
if (h->c.pict_type == AV_PICTURE_TYPE_P &&
h->c.mb_x + 1 < h->c.mb_width && h->mb_num_left != 1)
preview_obmc(h);
}
end:
if (get_bits_left(&h->gb) < 0)
return AVERROR_INVALIDDATA;
/* per-MB end of slice check */
{
int v = show_bits(&h->gb, 16);
if (get_bits_left(&h->gb) < 16) {
v >>= 16 - get_bits_left(&h->gb);
}
if(v==0)
return SLICE_END;
}
return SLICE_OK;
}
/* Most is hardcoded; should extend to handle all H.263 streams. */
int ff_h263_decode_picture_header(H263DecContext *const h)
{
int width, height, i, ret;
int h263_plus;
align_get_bits(&h->gb);
if (show_bits(&h->gb, 2) == 2 && h->c.avctx->frame_num == 0) {
av_log(h->c.avctx, AV_LOG_WARNING, "Header looks like RTP instead of H.263\n");
}
uint32_t startcode = get_bits(&h->gb, 22-8);
for (i = get_bits_left(&h->gb); i>24; i -= 8) {
startcode = ((startcode << 8) | get_bits(&h->gb, 8)) & 0x003FFFFF;
if(startcode == 0x20)
break;
}
if (startcode != 0x20) {
av_log(h->c.avctx, AV_LOG_ERROR, "Bad picture start code\n");
return -1;
}
/* temporal reference */
i = get_bits(&h->gb, 8); /* picture timestamp */
i -= (i - (h->picture_number & 0xFF) + 128) & ~0xFF;
h->picture_number = (h->picture_number&~0xFF) + i;
/* PTYPE starts here */
if (check_marker(h->c.avctx, &h->gb, "in PTYPE") != 1) {
return -1;
}
if (get_bits1(&h->gb) != 0) {
av_log(h->c.avctx, AV_LOG_ERROR, "Bad H.263 id\n");
return -1; /* H.263 id */
}
skip_bits1(&h->gb); /* split screen off */
skip_bits1(&h->gb); /* camera off */
skip_bits1(&h->gb); /* freeze picture release off */
int format = get_bits(&h->gb, 3);
/*
0 forbidden
1 sub-QCIF
10 QCIF
7 extended PTYPE (PLUSPTYPE)
*/
if (format != 7 && format != 6) {
h263_plus = 0;
/* H.263v1 */
width = ff_h263_format[format][0];
height = ff_h263_format[format][1];
if (!width)
return -1;
h->c.pict_type = AV_PICTURE_TYPE_I + get_bits1(&h->gb);
h->h263_long_vectors = get_bits1(&h->gb);
if (get_bits1(&h->gb) != 0) {
av_log(h->c.avctx, AV_LOG_ERROR, "H.263 SAC not supported\n");
return -1; /* SAC: off */
}
h->c.obmc = get_bits1(&h->gb); /* Advanced prediction mode */
h->pb_frame = get_bits1(&h->gb);
h->c.chroma_qscale = h->c.qscale = get_bits(&h->gb, 5);
skip_bits1(&h->gb); /* Continuous Presence Multipoint mode: off */
h->c.width = width;
h->c.height = height;
h->c.avctx->sample_aspect_ratio= (AVRational){12,11};
h->c.avctx->framerate = (AVRational){ 30000, 1001 };
} else {
int ufep;
/* H.263v2 */
h263_plus = 1;
ufep = get_bits(&h->gb, 3); /* Update Full Extended PTYPE */
/* ufep other than 0 and 1 are reserved */
if (ufep == 1) {
/* OPPTYPE */
format = get_bits(&h->gb, 3);
ff_dlog(h->c.avctx, "ufep=1, format: %d\n", format);
h->custom_pcf = get_bits1(&h->gb);
h->umvplus = get_bits1(&h->gb); /* Unrestricted Motion Vector */
if (get_bits1(&h->gb) != 0) {
av_log(h->c.avctx, AV_LOG_ERROR, "Syntax-based Arithmetic Coding (SAC) not supported\n");
}
h->c.obmc = get_bits1(&h->gb); /* Advanced prediction mode */
h->c.h263_aic = get_bits1(&h->gb); /* Advanced Intra Coding (AIC) */
h->loop_filter = get_bits1(&h->gb);
if (h->c.avctx->lowres)
h->loop_filter = 0;
h->h263_slice_structured = get_bits1(&h->gb);
if (get_bits1(&h->gb) != 0) {
av_log(h->c.avctx, AV_LOG_ERROR, "Reference Picture Selection not supported\n");
}
if (get_bits1(&h->gb) != 0) {
av_log(h->c.avctx, AV_LOG_ERROR, "Independent Segment Decoding not supported\n");
}
h->alt_inter_vlc = get_bits1(&h->gb);
h->modified_quant = get_bits1(&h->gb);
if (h->modified_quant)
h->c.chroma_qscale_table= ff_h263_chroma_qscale_table;
skip_bits(&h->gb, 1); /* Prevent start code emulation */
skip_bits(&h->gb, 3); /* Reserved */
} else if (ufep != 0) {
av_log(h->c.avctx, AV_LOG_ERROR, "Bad UFEP type (%d)\n", ufep);
return -1;
}
/* MPPTYPE */
h->c.pict_type = get_bits(&h->gb, 3);
switch (h->c.pict_type) {
case 0: h->c.pict_type = AV_PICTURE_TYPE_I; break;
case 1: h->c.pict_type = AV_PICTURE_TYPE_P; break;
case 2: h->c.pict_type = AV_PICTURE_TYPE_P; h->pb_frame = 3; break;
case 3: h->c.pict_type = AV_PICTURE_TYPE_B; break;
case 7: h->c.pict_type = AV_PICTURE_TYPE_I; break; //ZYGO
default:
return -1;
}
skip_bits(&h->gb, 2);
h->c.no_rounding = get_bits1(&h->gb);
skip_bits(&h->gb, 4);
/* Get the picture dimensions */
if (ufep) {
if (format == 6) {
/* Custom Picture Format (CPFMT) */
int aspect_ratio_info = get_bits(&h->gb, 4);
ff_dlog(h->c.avctx, "aspect: %d\n", aspect_ratio_info);
/* aspect ratios:
0 - forbidden
1 - 1:1
2 - 12:11 (CIF 4:3)
3 - 10:11 (525-type 4:3)
4 - 16:11 (CIF 16:9)
5 - 40:33 (525-type 16:9)
6-14 - reserved
*/
width = (get_bits(&h->gb, 9) + 1) * 4;
check_marker(h->c.avctx, &h->gb, "in dimensions");
height = get_bits(&h->gb, 9) * 4;
ff_dlog(h->c.avctx, "\nH.263+ Custom picture: %dx%d\n",width,height);
if (aspect_ratio_info == FF_ASPECT_EXTENDED) {
/* expected dimensions */
h->c.avctx->sample_aspect_ratio.num = get_bits(&h->gb, 8);
h->c.avctx->sample_aspect_ratio.den = get_bits(&h->gb, 8);
}else{
h->c.avctx->sample_aspect_ratio= ff_h263_pixel_aspect[aspect_ratio_info];
}
} else {
width = ff_h263_format[format][0];
height = ff_h263_format[format][1];
h->c.avctx->sample_aspect_ratio = (AVRational){12,11};
}
h->c.avctx->sample_aspect_ratio.den <<= h->ehc_mode;
if ((width == 0) || (height == 0))
return -1;
h->c.width = width;
h->c.height = height;
if (h->custom_pcf) {
h->c.avctx->framerate.num = 1800000;
h->c.avctx->framerate.den = 1000 + get_bits1(&h->gb);
h->c.avctx->framerate.den *= get_bits(&h->gb, 7);
if (h->c.avctx->framerate.den == 0) {
av_log(h->c.avctx, AV_LOG_ERROR, "zero framerate\n");
return -1;
}
int gcd = av_gcd(h->c.avctx->framerate.den, h->c.avctx->framerate.num);
h->c.avctx->framerate.den /= gcd;
h->c.avctx->framerate.num /= gcd;
}else{
h->c.avctx->framerate = (AVRational){ 30000, 1001 };
}
}
if (h->custom_pcf)
skip_bits(&h->gb, 2); //extended Temporal reference
if (ufep) {
if (h->umvplus) {
if (get_bits1(&h->gb)==0) /* Unlimited Unrestricted Motion Vectors Indicator (UUI) */
skip_bits1(&h->gb);
}
if (h->h263_slice_structured) {
if (get_bits1(&h->gb) != 0) {
av_log(h->c.avctx, AV_LOG_ERROR, "rectangular slices not supported\n");
}
if (get_bits1(&h->gb) != 0) {
av_log(h->c.avctx, AV_LOG_ERROR, "unordered slices not supported\n");
}
}
if (h->c.pict_type == AV_PICTURE_TYPE_B) {
skip_bits(&h->gb, 4); //ELNUM
if (ufep == 1) {
skip_bits(&h->gb, 4); // RLNUM
}
}
}
h->c.qscale = get_bits(&h->gb, 5);
}
ret = av_image_check_size(h->c.width, h->c.height, 0, h->c.avctx);
if (ret < 0)
return ret;
if (!(h->c.avctx->flags2 & AV_CODEC_FLAG2_CHUNKS)) {
if ((h->c.width * h->c.height / 256 / 8) > get_bits_left(&h->gb))
return AVERROR_INVALIDDATA;
}
h->c.mb_width = (h->c.width + 15U) / 16;
h->c.mb_height = (h->c.height + 15U) / 16;
h->c.mb_num = h->c.mb_width * h->c.mb_height;
h->gob_index = H263_GOB_HEIGHT(h->c.height);
if (h->pb_frame) {
skip_bits(&h->gb, 3); /* Temporal reference for B-pictures */
if (h->custom_pcf)
skip_bits(&h->gb, 2); //extended Temporal reference
skip_bits(&h->gb, 2); /* Quantization information for B-pictures */
}
if (h->c.pict_type!=AV_PICTURE_TYPE_B) {
h->c.time = h->picture_number;
h->c.pp_time = h->c.time - h->c.last_non_b_time;
h->c.last_non_b_time = h->c.time;
}else{
h->c.time = h->picture_number;
h->c.pb_time = h->c.pp_time - (h->c.last_non_b_time - h->c.time);
if (h->c.pp_time <= h->c.pb_time ||
h->c.pp_time <= h->c.pp_time - h->c.pb_time ||
h->c.pp_time <= 0) {
h->c.pp_time = 2;
h->c.pb_time = 1;
}
ff_mpeg4_init_direct_mv(&h->c);
}
/* PEI */
if (skip_1stop_8data_bits(&h->gb) < 0)
return AVERROR_INVALIDDATA;
if (h->h263_slice_structured) {
if (check_marker(h->c.avctx, &h->gb, "SEPB1") != 1) {
return -1;
}
ff_h263_decode_mba(h);
if (check_marker(h->c.avctx, &h->gb, "SEPB2") != 1) {
return -1;
}
}
if (h->c.pict_type == AV_PICTURE_TYPE_B)
h->c.low_delay = 0;
if (h->c.h263_aic) {
h->c.y_dc_scale_table =
h->c.c_dc_scale_table = ff_aic_dc_scale_table;
}else{
h->c.y_dc_scale_table =
h->c.c_dc_scale_table = ff_mpeg1_dc_scale_table;
}
ff_h263_show_pict_info(h, h263_plus);
if (h->c.pict_type == AV_PICTURE_TYPE_I && h->c.codec_tag == AV_RL32("ZYGO") && get_bits_left(&h->gb) >= 85 + 13*3*16 + 50){
int i,j;
for(i=0; i<85; i++) av_log(h->c.avctx, AV_LOG_DEBUG, "%d", get_bits1(&h->gb));
av_log(h->c.avctx, AV_LOG_DEBUG, "\n");
for(i=0; i<13; i++){
for(j=0; j<3; j++){
int v= get_bits(&h->gb, 8);
v |= get_sbits(&h->gb, 8) * (1 << 8);
av_log(h->c.avctx, AV_LOG_DEBUG, " %5d", v);
}
av_log(h->c.avctx, AV_LOG_DEBUG, "\n");
}
for(i=0; i<50; i++) av_log(h->c.avctx, AV_LOG_DEBUG, "%d", get_bits1(&h->gb));
}
return 0;
}