* Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
* Copyright (c) 2004 Maarten Daniels
*
- * This file is part of FFmpeg.
+ * This file is part of Libav.
*
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav 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,
+ * Libav 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
+ * License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
- * @file libavcodec/h261dec.c
+ * @file
* H.261 decoder.
*/
-#include "dsputil.h"
#include "avcodec.h"
+#include "mpeg_er.h"
+#include "mpegutils.h"
#include "mpegvideo.h"
+#include "h263.h"
#include "h261.h"
-#include "h261data.h"
+#include "internal.h"
#define H261_MBA_VLC_BITS 9
#define H261_MTYPE_VLC_BITS 6
#define MBA_STUFFING 33
#define MBA_STARTCODE 34
-extern uint8_t ff_h261_rl_table_store[2][2*MAX_RUN + MAX_LEVEL + 3];
-
static VLC h261_mba_vlc;
static VLC h261_mtype_vlc;
static VLC h261_mv_vlc;
static VLC h261_cbp_vlc;
-static int h261_decode_block(H261Context * h, DCTELEM * block, int n, int coded);
-
-static av_cold void h261_decode_init_vlc(H261Context *h){
+static av_cold void h261_decode_init_vlc(H261Context *h)
+{
static int done = 0;
- if(!done){
+ if (!done) {
done = 1;
- init_vlc(&h261_mba_vlc, H261_MBA_VLC_BITS, 35,
- h261_mba_bits, 1, 1,
- h261_mba_code, 1, 1, 1);
- init_vlc(&h261_mtype_vlc, H261_MTYPE_VLC_BITS, 10,
- h261_mtype_bits, 1, 1,
- h261_mtype_code, 1, 1, 1);
- init_vlc(&h261_mv_vlc, H261_MV_VLC_BITS, 17,
- &h261_mv_tab[0][1], 2, 1,
- &h261_mv_tab[0][0], 2, 1, 1);
- init_vlc(&h261_cbp_vlc, H261_CBP_VLC_BITS, 63,
- &h261_cbp_tab[0][1], 2, 1,
- &h261_cbp_tab[0][0], 2, 1, 1);
- init_rl(&h261_rl_tcoeff, ff_h261_rl_table_store);
- INIT_VLC_RL(h261_rl_tcoeff, 552);
+ INIT_VLC_STATIC(&h261_mba_vlc, H261_MBA_VLC_BITS, 35,
+ ff_h261_mba_bits, 1, 1,
+ ff_h261_mba_code, 1, 1, 662);
+ INIT_VLC_STATIC(&h261_mtype_vlc, H261_MTYPE_VLC_BITS, 10,
+ ff_h261_mtype_bits, 1, 1,
+ ff_h261_mtype_code, 1, 1, 80);
+ INIT_VLC_STATIC(&h261_mv_vlc, H261_MV_VLC_BITS, 17,
+ &ff_h261_mv_tab[0][1], 2, 1,
+ &ff_h261_mv_tab[0][0], 2, 1, 144);
+ INIT_VLC_STATIC(&h261_cbp_vlc, H261_CBP_VLC_BITS, 63,
+ &ff_h261_cbp_tab[0][1], 2, 1,
+ &ff_h261_cbp_tab[0][0], 2, 1, 512);
+ INIT_VLC_RL(ff_h261_rl_tcoeff, 552);
}
}
-static av_cold int h261_decode_init(AVCodecContext *avctx){
- H261Context *h= avctx->priv_data;
- MpegEncContext * const s = &h->s;
+static av_cold int h261_decode_init(AVCodecContext *avctx)
+{
+ H261Context *h = avctx->priv_data;
+ MpegEncContext *const s = &h->s;
// set defaults
- MPV_decode_defaults(s);
- s->avctx = avctx;
-
- s->width = s->avctx->coded_width;
- s->height = s->avctx->coded_height;
- s->codec_id = s->avctx->codec->id;
-
- s->out_format = FMT_H261;
- s->low_delay= 1;
- avctx->pix_fmt= PIX_FMT_YUV420P;
-
- s->codec_id= avctx->codec->id;
-
+ ff_mpv_decode_defaults(s);
+ s->avctx = avctx;
+ s->width = s->avctx->coded_width;
+ s->height = s->avctx->coded_height;
+ s->codec_id = s->avctx->codec->id;
+ s->out_format = FMT_H261;
+ s->low_delay = 1;
+ avctx->pix_fmt = AV_PIX_FMT_YUV420P;
+ s->codec_id = avctx->codec->id;
+
+ ff_h261_common_init();
h261_decode_init_vlc(h);
h->gob_start_code_skipped = 0;
}
/**
- * decodes the group of blocks header or slice header.
+ * Decode the group of blocks header or slice header.
* @return <0 if an error occurred
*/
-static int h261_decode_gob_header(H261Context *h){
+static int h261_decode_gob_header(H261Context *h)
+{
unsigned int val;
- MpegEncContext * const s = &h->s;
+ MpegEncContext *const s = &h->s;
- if ( !h->gob_start_code_skipped ){
+ if (!h->gob_start_code_skipped) {
/* Check for GOB Start Code */
val = show_bits(&s->gb, 15);
- if(val)
+ if (val)
return -1;
/* We have a GBSC */
h->gob_start_code_skipped = 0;
h->gob_number = get_bits(&s->gb, 4); /* GN */
- s->qscale = get_bits(&s->gb, 5); /* GQUANT */
+ s->qscale = get_bits(&s->gb, 5); /* GQUANT */
/* Check if gob_number is valid */
- if (s->mb_height==18){ //cif
- if ((h->gob_number<=0) || (h->gob_number>12))
+ if (s->mb_height == 18) { // CIF
+ if ((h->gob_number <= 0) || (h->gob_number > 12))
return -1;
- }
- else{ //qcif
- if ((h->gob_number!=1) && (h->gob_number!=3) && (h->gob_number!=5))
+ } else { // QCIF
+ if ((h->gob_number != 1) && (h->gob_number != 3) &&
+ (h->gob_number != 5))
return -1;
}
/* GEI */
- while (get_bits1(&s->gb) != 0) {
+ while (get_bits1(&s->gb) != 0)
skip_bits(&s->gb, 8);
- }
- if(s->qscale==0) {
+ if (s->qscale == 0) {
av_log(s->avctx, AV_LOG_ERROR, "qscale has forbidden 0 value\n");
- if (s->avctx->error_recognition >= FF_ER_COMPLIANT)
+ if (s->avctx->err_recognition & AV_EF_BITSTREAM)
return -1;
}
- // For the first transmitted macroblock in a GOB, MBA is the absolute address. For
- // subsequent macroblocks, MBA is the difference between the absolute addresses of
- // the macroblock and the last transmitted macroblock.
+ /* For the first transmitted macroblock in a GOB, MBA is the absolute
+ * address. For subsequent macroblocks, MBA is the difference between
+ * the absolute addresses of the macroblock and the last transmitted
+ * macroblock. */
h->current_mba = 0;
- h->mba_diff = 0;
+ h->mba_diff = 0;
return 0;
}
/**
- * decodes the group of blocks / video packet header.
+ * Decode the group of blocks / video packet header.
* @return <0 if no resync found
*/
-static int ff_h261_resync(H261Context *h){
- MpegEncContext * const s = &h->s;
+static int h261_resync(H261Context *h)
+{
+ MpegEncContext *const s = &h->s;
int left, ret;
- if ( h->gob_start_code_skipped ){
- ret= h261_decode_gob_header(h);
- if(ret>=0)
+ if (h->gob_start_code_skipped) {
+ ret = h261_decode_gob_header(h);
+ if (ret >= 0)
return 0;
- }
- else{
- if(show_bits(&s->gb, 15)==0){
- ret= h261_decode_gob_header(h);
- if(ret>=0)
+ } else {
+ if (show_bits(&s->gb, 15) == 0) {
+ ret = h261_decode_gob_header(h);
+ if (ret >= 0)
return 0;
}
- //OK, it is not where it is supposed to be ...
- s->gb= s->last_resync_gb;
+ // OK, it is not where it is supposed to be ...
+ s->gb = s->last_resync_gb;
align_get_bits(&s->gb);
- left= s->gb.size_in_bits - get_bits_count(&s->gb);
+ left = get_bits_left(&s->gb);
- for(;left>15+1+4+5; left-=8){
- if(show_bits(&s->gb, 15)==0){
- GetBitContext bak= s->gb;
+ for (; left > 15 + 1 + 4 + 5; left -= 8) {
+ if (show_bits(&s->gb, 15) == 0) {
+ GetBitContext bak = s->gb;
- ret= h261_decode_gob_header(h);
- if(ret>=0)
+ ret = h261_decode_gob_header(h);
+ if (ret >= 0)
return 0;
- s->gb= bak;
+ s->gb = bak;
}
skip_bits(&s->gb, 8);
}
}
/**
- * decodes skipped macroblocks
+ * Decode skipped macroblocks.
* @return 0
*/
-static int h261_decode_mb_skipped(H261Context *h, int mba1, int mba2 )
+static int h261_decode_mb_skipped(H261Context *h, int mba1, int mba2)
{
- MpegEncContext * const s = &h->s;
+ MpegEncContext *const s = &h->s;
int i;
s->mb_intra = 0;
- for(i=mba1; i<mba2; i++){
+ for (i = mba1; i < mba2; i++) {
int j, xy;
- s->mb_x= ((h->gob_number-1) % 2) * 11 + i % 11;
- s->mb_y= ((h->gob_number-1) / 2) * 3 + i / 11;
- xy = s->mb_x + s->mb_y * s->mb_stride;
+ s->mb_x = ((h->gob_number - 1) % 2) * 11 + i % 11;
+ s->mb_y = ((h->gob_number - 1) / 2) * 3 + i / 11;
+ xy = s->mb_x + s->mb_y * s->mb_stride;
ff_init_block_index(s);
ff_update_block_index(s);
- for(j=0;j<6;j++)
+ for (j = 0; j < 6; j++)
s->block_last_index[j] = -1;
- s->mv_dir = MV_DIR_FORWARD;
- s->mv_type = MV_TYPE_16X16;
- s->current_picture.mb_type[xy]= MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
- s->mv[0][0][0] = 0;
- s->mv[0][0][1] = 0;
- s->mb_skipped = 1;
- h->mtype &= ~MB_TYPE_H261_FIL;
+ s->mv_dir = MV_DIR_FORWARD;
+ s->mv_type = MV_TYPE_16X16;
+ s->current_picture.mb_type[xy] = MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
+ s->mv[0][0][0] = 0;
+ s->mv[0][0][1] = 0;
+ s->mb_skipped = 1;
+ h->mtype &= ~MB_TYPE_H261_FIL;
- MPV_decode_mb(s, s->block);
+ ff_mpv_decode_mb(s, s->block);
}
return 0;
}
-static int decode_mv_component(GetBitContext *gb, int v){
+static const int mvmap[17] = {
+ 0, -1, -2, -3, -4, -5, -6, -7, -8, -9, -10, -11, -12, -13, -14, -15, -16
+};
+
+static int decode_mv_component(GetBitContext *gb, int v)
+{
int mv_diff = get_vlc2(gb, h261_mv_vlc.table, H261_MV_VLC_BITS, 2);
/* check if mv_diff is valid */
- if ( mv_diff < 0 )
+ if (mv_diff < 0)
return v;
mv_diff = mvmap[mv_diff];
- if(mv_diff && !get_bits1(gb))
- mv_diff= -mv_diff;
+ if (mv_diff && !get_bits1(gb))
+ mv_diff = -mv_diff;
v += mv_diff;
- if (v <=-16) v+= 32;
- else if(v >= 16) v-= 32;
+ if (v <= -16)
+ v += 32;
+ else if (v >= 16)
+ v -= 32;
return v;
}
-static int h261_decode_mb(H261Context *h){
- MpegEncContext * const s = &h->s;
+/**
+ * Decode a macroblock.
+ * @return <0 if an error occurred
+ */
+static int h261_decode_block(H261Context *h, int16_t *block, int n, int coded)
+{
+ MpegEncContext *const s = &h->s;
+ int code, level, i, j, run;
+ RLTable *rl = &ff_h261_rl_tcoeff;
+ const uint8_t *scan_table;
+
+ /* For the variable length encoding there are two code tables, one being
+ * used for the first transmitted LEVEL in INTER, INTER + MC and
+ * INTER + MC + FIL blocks, the second for all other LEVELs except the
+ * first one in INTRA blocks which is fixed length coded with 8 bits.
+ * NOTE: The two code tables only differ in one VLC so we handle that
+ * manually. */
+ scan_table = s->intra_scantable.permutated;
+ if (s->mb_intra) {
+ /* DC coef */
+ level = get_bits(&s->gb, 8);
+ // 0 (00000000b) and -128 (10000000b) are FORBIDDEN
+ if ((level & 0x7F) == 0) {
+ av_log(s->avctx, AV_LOG_ERROR, "illegal dc %d at %d %d\n",
+ level, s->mb_x, s->mb_y);
+ return -1;
+ }
+ /* The code 1000 0000 is not used, the reconstruction level of 1024
+ * being coded as 1111 1111. */
+ if (level == 255)
+ level = 128;
+ block[0] = level;
+ i = 1;
+ } else if (coded) {
+ // Run Level Code
+ // EOB Not possible for first level when cbp is available (that's why the table is different)
+ // 0 1 1s
+ // * * 0*
+ int check = show_bits(&s->gb, 2);
+ i = 0;
+ if (check & 0x2) {
+ skip_bits(&s->gb, 2);
+ block[0] = (check & 0x1) ? -1 : 1;
+ i = 1;
+ }
+ } else {
+ i = 0;
+ }
+ if (!coded) {
+ s->block_last_index[n] = i - 1;
+ return 0;
+ }
+ for (;;) {
+ code = get_vlc2(&s->gb, rl->vlc.table, TCOEFF_VLC_BITS, 2);
+ if (code < 0) {
+ av_log(s->avctx, AV_LOG_ERROR, "illegal ac vlc code at %dx%d\n",
+ s->mb_x, s->mb_y);
+ return -1;
+ }
+ if (code == rl->n) {
+ /* escape */
+ /* The remaining combinations of (run, level) are encoded with a
+ * 20-bit word consisting of 6 bits escape, 6 bits run and 8 bits
+ * level. */
+ run = get_bits(&s->gb, 6);
+ level = get_sbits(&s->gb, 8);
+ } else if (code == 0) {
+ break;
+ } else {
+ run = rl->table_run[code];
+ level = rl->table_level[code];
+ if (get_bits1(&s->gb))
+ level = -level;
+ }
+ i += run;
+ if (i >= 64) {
+ av_log(s->avctx, AV_LOG_ERROR, "run overflow at %dx%d\n",
+ s->mb_x, s->mb_y);
+ return -1;
+ }
+ j = scan_table[i];
+ block[j] = level;
+ i++;
+ }
+ s->block_last_index[n] = i - 1;
+ return 0;
+}
+
+static int h261_decode_mb(H261Context *h)
+{
+ MpegEncContext *const s = &h->s;
int i, cbp, xy;
cbp = 63;
// Read mba
- do{
- h->mba_diff = get_vlc2(&s->gb, h261_mba_vlc.table, H261_MBA_VLC_BITS, 2);
+ do {
+ h->mba_diff = get_vlc2(&s->gb, h261_mba_vlc.table,
+ H261_MBA_VLC_BITS, 2);
/* Check for slice end */
/* NOTE: GOB can be empty (no MB data) or exist only of MBA_stuffing */
- if (h->mba_diff == MBA_STARTCODE){ // start code
+ if (h->mba_diff == MBA_STARTCODE) { // start code
h->gob_start_code_skipped = 1;
return SLICE_END;
}
- }
- while( h->mba_diff == MBA_STUFFING ); // stuffing
+ } while (h->mba_diff == MBA_STUFFING); // stuffing
- if ( h->mba_diff < 0 ){
- if ( get_bits_count(&s->gb) + 7 >= s->gb.size_in_bits )
+ if (h->mba_diff < 0) {
+ if (get_bits_left(&s->gb) <= 7)
return SLICE_END;
av_log(s->avctx, AV_LOG_ERROR, "illegal mba at %d %d\n", s->mb_x, s->mb_y);
return SLICE_ERROR;
}
- h->mba_diff += 1;
+ h->mba_diff += 1;
h->current_mba += h->mba_diff;
- if ( h->current_mba > MBA_STUFFING )
+ if (h->current_mba > MBA_STUFFING)
return SLICE_ERROR;
- s->mb_x= ((h->gob_number-1) % 2) * 11 + ((h->current_mba-1) % 11);
- s->mb_y= ((h->gob_number-1) / 2) * 3 + ((h->current_mba-1) / 11);
- xy = s->mb_x + s->mb_y * s->mb_stride;
+ s->mb_x = ((h->gob_number - 1) % 2) * 11 + ((h->current_mba - 1) % 11);
+ s->mb_y = ((h->gob_number - 1) / 2) * 3 + ((h->current_mba - 1) / 11);
+ xy = s->mb_x + s->mb_y * s->mb_stride;
ff_init_block_index(s);
ff_update_block_index(s);
// Read mtype
h->mtype = get_vlc2(&s->gb, h261_mtype_vlc.table, H261_MTYPE_VLC_BITS, 2);
- h->mtype = h261_mtype_map[h->mtype];
+ if (h->mtype < 0 || h->mtype >= FF_ARRAY_ELEMS(ff_h261_mtype_map)) {
+ av_log(s->avctx, AV_LOG_ERROR, "Invalid mtype index %d\n",
+ h->mtype);
+ return SLICE_ERROR;
+ }
+ h->mtype = ff_h261_mtype_map[h->mtype];
// Read mquant
- if ( IS_QUANT ( h->mtype ) ){
+ if (IS_QUANT(h->mtype))
ff_set_qscale(s, get_bits(&s->gb, 5));
- }
s->mb_intra = IS_INTRA4x4(h->mtype);
// Read mv
- if ( IS_16X16 ( h->mtype ) ){
- // Motion vector data is included for all MC macroblocks. MVD is obtained from the macroblock vector by subtracting the
- // vector of the preceding macroblock. For this calculation the vector of the preceding macroblock is regarded as zero in the
- // following three situations:
- // 1) evaluating MVD for macroblocks 1, 12 and 23;
- // 2) evaluating MVD for macroblocks in which MBA does not represent a difference of 1;
- // 3) MTYPE of the previous macroblock was not MC.
- if ( ( h->current_mba == 1 ) || ( h->current_mba == 12 ) || ( h->current_mba == 23 ) ||
- ( h->mba_diff != 1))
- {
+ if (IS_16X16(h->mtype)) {
+ /* Motion vector data is included for all MC macroblocks. MVD is
+ * obtained from the macroblock vector by subtracting the vector
+ * of the preceding macroblock. For this calculation the vector
+ * of the preceding macroblock is regarded as zero in the
+ * following three situations:
+ * 1) evaluating MVD for macroblocks 1, 12 and 23;
+ * 2) evaluating MVD for macroblocks in which MBA does not represent a difference of 1;
+ * 3) MTYPE of the previous macroblock was not MC. */
+ if ((h->current_mba == 1) || (h->current_mba == 12) ||
+ (h->current_mba == 23) || (h->mba_diff != 1)) {
h->current_mv_x = 0;
h->current_mv_y = 0;
}
- h->current_mv_x= decode_mv_component(&s->gb, h->current_mv_x);
- h->current_mv_y= decode_mv_component(&s->gb, h->current_mv_y);
- }else{
+ h->current_mv_x = decode_mv_component(&s->gb, h->current_mv_x);
+ h->current_mv_y = decode_mv_component(&s->gb, h->current_mv_y);
+ } else {
h->current_mv_x = 0;
h->current_mv_y = 0;
}
// Read cbp
- if ( HAS_CBP( h->mtype ) ){
+ if (HAS_CBP(h->mtype))
cbp = get_vlc2(&s->gb, h261_cbp_vlc.table, H261_CBP_VLC_BITS, 2) + 1;
- }
- if(s->mb_intra){
- s->current_picture.mb_type[xy]= MB_TYPE_INTRA;
+ if (s->mb_intra) {
+ s->current_picture.mb_type[xy] = MB_TYPE_INTRA;
goto intra;
}
//set motion vectors
- s->mv_dir = MV_DIR_FORWARD;
- s->mv_type = MV_TYPE_16X16;
- s->current_picture.mb_type[xy]= MB_TYPE_16x16 | MB_TYPE_L0;
- s->mv[0][0][0] = h->current_mv_x * 2;//gets divided by 2 in motion compensation
- s->mv[0][0][1] = h->current_mv_y * 2;
+ s->mv_dir = MV_DIR_FORWARD;
+ s->mv_type = MV_TYPE_16X16;
+ s->current_picture.mb_type[xy] = MB_TYPE_16x16 | MB_TYPE_L0;
+ s->mv[0][0][0] = h->current_mv_x * 2; // gets divided by 2 in motion compensation
+ s->mv[0][0][1] = h->current_mv_y * 2;
intra:
/* decode each block */
- if(s->mb_intra || HAS_CBP(h->mtype)){
- s->dsp.clear_blocks(s->block[0]);
+ if (s->mb_intra || HAS_CBP(h->mtype)) {
+ s->bdsp.clear_blocks(s->block[0]);
for (i = 0; i < 6; i++) {
- if (h261_decode_block(h, s->block[i], i, cbp&32) < 0){
+ if (h261_decode_block(h, s->block[i], i, cbp & 32) < 0)
return SLICE_ERROR;
- }
- cbp+=cbp;
+ cbp += cbp;
}
- }else{
+ } else {
for (i = 0; i < 6; i++)
- s->block_last_index[i]= -1;
+ s->block_last_index[i] = -1;
}
- MPV_decode_mb(s, s->block);
+ ff_mpv_decode_mb(s, s->block);
return SLICE_OK;
}
/**
- * decodes a macroblock
- * @return <0 if an error occurred
- */
-static int h261_decode_block(H261Context * h, DCTELEM * block,
- int n, int coded)
-{
- MpegEncContext * const s = &h->s;
- int code, level, i, j, run;
- RLTable *rl = &h261_rl_tcoeff;
- const uint8_t *scan_table;
-
- // For the variable length encoding there are two code tables, one being used for
- // the first transmitted LEVEL in INTER, INTER+MC and INTER+MC+FIL blocks, the second
- // for all other LEVELs except the first one in INTRA blocks which is fixed length
- // coded with 8 bits.
- // NOTE: the two code tables only differ in one VLC so we handle that manually.
- scan_table = s->intra_scantable.permutated;
- if (s->mb_intra){
- /* DC coef */
- level = get_bits(&s->gb, 8);
- // 0 (00000000b) and -128 (10000000b) are FORBIDDEN
- if((level&0x7F) == 0){
- av_log(s->avctx, AV_LOG_ERROR, "illegal dc %d at %d %d\n", level, s->mb_x, s->mb_y);
- return -1;
- }
- // The code 1000 0000 is not used, the reconstruction level of 1024 being coded as 1111 1111.
- if (level == 255)
- level = 128;
- block[0] = level;
- i = 1;
- }else if(coded){
- // Run Level Code
- // EOB Not possible for first level when cbp is available (that's why the table is different)
- // 0 1 1s
- // * * 0*
- int check = show_bits(&s->gb, 2);
- i = 0;
- if ( check & 0x2 ){
- skip_bits(&s->gb, 2);
- block[0] = ( check & 0x1 ) ? -1 : 1;
- i = 1;
- }
- }else{
- i = 0;
- }
- if(!coded){
- s->block_last_index[n] = i - 1;
- return 0;
- }
- for(;;){
- code = get_vlc2(&s->gb, rl->vlc.table, TCOEFF_VLC_BITS, 2);
- if (code < 0){
- av_log(s->avctx, AV_LOG_ERROR, "illegal ac vlc code at %dx%d\n", s->mb_x, s->mb_y);
- return -1;
- }
- if (code == rl->n) {
- /* escape */
- // The remaining combinations of (run, level) are encoded with a 20-bit word consisting of 6 bits escape, 6 bits run and 8 bits level.
- run = get_bits(&s->gb, 6);
- level = get_sbits(&s->gb, 8);
- }else if(code == 0){
- break;
- }else{
- run = rl->table_run[code];
- level = rl->table_level[code];
- if (get_bits1(&s->gb))
- level = -level;
- }
- i += run;
- if (i >= 64){
- av_log(s->avctx, AV_LOG_ERROR, "run overflow at %dx%d\n", s->mb_x, s->mb_y);
- return -1;
- }
- j = scan_table[i];
- block[j] = level;
- i++;
- }
- s->block_last_index[n] = i-1;
- return 0;
-}
-
-/**
- * decodes the H261 picture header.
+ * Decode the H.261 picture header.
* @return <0 if no startcode found
*/
-static int h261_decode_picture_header(H261Context *h){
- MpegEncContext * const s = &h->s;
+static int h261_decode_picture_header(H261Context *h)
+{
+ MpegEncContext *const s = &h->s;
int format, i;
- uint32_t startcode= 0;
+ uint32_t startcode = 0;
- for(i= s->gb.size_in_bits - get_bits_count(&s->gb); i>24; i-=1){
+ for (i = get_bits_left(&s->gb); i > 24; i -= 1) {
startcode = ((startcode << 1) | get_bits(&s->gb, 1)) & 0x000FFFFF;
- if(startcode == 0x10)
+ if (startcode == 0x10)
break;
}
- if (startcode != 0x10){
+ if (startcode != 0x10) {
av_log(s->avctx, AV_LOG_ERROR, "Bad picture start code\n");
return -1;
}
/* temporal reference */
- i= get_bits(&s->gb, 5); /* picture timestamp */
- if(i < (s->picture_number&31))
+ i = get_bits(&s->gb, 5); /* picture timestamp */
+ if (i < (s->picture_number & 31))
i += 32;
- s->picture_number = (s->picture_number&~31) + i;
-
- s->avctx->time_base= (AVRational){1001, 30000};
- s->current_picture.pts= s->picture_number;
+ s->picture_number = (s->picture_number & ~31) + i;
+ s->avctx->framerate = (AVRational) { 30000, 1001 };
/* PTYPE starts here */
skip_bits1(&s->gb); /* split screen off */
format = get_bits1(&s->gb);
- //only 2 formats possible
- if (format == 0){//QCIF
- s->width = 176;
- s->height = 144;
- s->mb_width = 11;
+ // only 2 formats possible
+ if (format == 0) { // QCIF
+ s->width = 176;
+ s->height = 144;
+ s->mb_width = 11;
s->mb_height = 9;
- }else{//CIF
- s->width = 352;
- s->height = 288;
- s->mb_width = 22;
+ } else { // CIF
+ s->width = 352;
+ s->height = 288;
+ s->mb_width = 22;
s->mb_height = 18;
}
skip_bits1(&s->gb); /* Reserved */
/* PEI */
- while (get_bits1(&s->gb) != 0){
+ while (get_bits1(&s->gb) != 0)
skip_bits(&s->gb, 8);
- }
- // h261 has no I-FRAMES, but if we pass FF_I_TYPE for the first frame, the codec crashes if it does
- // not contain all I-blocks (e.g. when a packet is lost)
- s->pict_type = FF_P_TYPE;
+ /* H.261 has no I-frames, but if we pass AV_PICTURE_TYPE_I for the first
+ * frame, the codec crashes if it does not contain all I-blocks
+ * (e.g. when a packet is lost). */
+ s->pict_type = AV_PICTURE_TYPE_P;
h->gob_number = 0;
return 0;
}
-static int h261_decode_gob(H261Context *h){
- MpegEncContext * const s = &h->s;
+static int h261_decode_gob(H261Context *h)
+{
+ MpegEncContext *const s = &h->s;
ff_set_qscale(s, s->qscale);
/* decode mb's */
- while(h->current_mba <= MBA_STUFFING)
- {
+ while (h->current_mba <= MBA_STUFFING) {
int ret;
/* DCT & quantize */
- ret= h261_decode_mb(h);
- if(ret<0){
- if(ret==SLICE_END){
+ ret = h261_decode_mb(h);
+ if (ret < 0) {
+ if (ret == SLICE_END) {
h261_decode_mb_skipped(h, h->current_mba, 33);
return 0;
}
- av_log(s->avctx, AV_LOG_ERROR, "Error at MB: %d\n", s->mb_x + s->mb_y*s->mb_stride);
+ av_log(s->avctx, AV_LOG_ERROR, "Error at MB: %d\n",
+ s->mb_x + s->mb_y * s->mb_stride);
return -1;
}
- h261_decode_mb_skipped(h, h->current_mba-h->mba_diff, h->current_mba-1);
+ h261_decode_mb_skipped(h,
+ h->current_mba - h->mba_diff,
+ h->current_mba - 1);
}
return -1;
/**
* returns the number of bytes consumed for building the current frame
*/
-static int get_consumed_bytes(MpegEncContext *s, int buf_size){
- int pos= get_bits_count(&s->gb)>>3;
- if(pos==0) pos=1; //avoid infinite loops (i doubt that is needed but ...)
- if(pos+10>buf_size) pos=buf_size; // oops ;)
+static int get_consumed_bytes(MpegEncContext *s, int buf_size)
+{
+ int pos = get_bits_count(&s->gb) >> 3;
+ if (pos == 0)
+ pos = 1; // avoid infinite loops (i doubt that is needed but ...)
+ if (pos + 10 > buf_size)
+ pos = buf_size; // oops ;)
return pos;
}
-static int h261_decode_frame(AVCodecContext *avctx,
- void *data, int *data_size,
- const uint8_t *buf, int buf_size)
+static int h261_decode_frame(AVCodecContext *avctx, void *data,
+ int *got_frame, AVPacket *avpkt)
{
- H261Context *h= avctx->priv_data;
- MpegEncContext *s = &h->s;
+ const uint8_t *buf = avpkt->data;
+ int buf_size = avpkt->size;
+ H261Context *h = avctx->priv_data;
+ MpegEncContext *s = &h->s;
int ret;
AVFrame *pict = data;
-#ifdef DEBUG
- av_log(avctx, AV_LOG_DEBUG, "*****frame %d size=%d\n", avctx->frame_number, buf_size);
- av_log(avctx, AV_LOG_DEBUG, "bytes=%x %x %x %x\n", buf[0], buf[1], buf[2], buf[3]);
-#endif
- s->flags= avctx->flags;
- s->flags2= avctx->flags2;
+ ff_dlog(avctx, "*****frame %d size=%d\n", avctx->frame_number, buf_size);
+ ff_dlog(avctx, "bytes=%x %x %x %x\n", buf[0], buf[1], buf[2], buf[3]);
- h->gob_start_code_skipped=0;
+ h->gob_start_code_skipped = 0;
retry:
+ init_get_bits(&s->gb, buf, buf_size * 8);
- init_get_bits(&s->gb, buf, buf_size*8);
-
- if(!s->context_initialized){
- if (MPV_common_init(s) < 0) //we need the idct permutaton for reading a custom matrix
- return -1;
- }
-
- //we need to set current_picture_ptr before reading the header, otherwise we cannot store anyting im there
- if(s->current_picture_ptr==NULL || s->current_picture_ptr->data[0]){
- int i= ff_find_unused_picture(s, 0);
- s->current_picture_ptr= &s->picture[i];
- }
+ if (!s->context_initialized)
+ // we need the IDCT permutaton for reading a custom matrix
+ ff_mpv_idct_init(s);
ret = h261_decode_picture_header(h);
/* skip if the header was thrashed */
- if (ret < 0){
+ if (ret < 0) {
av_log(s->avctx, AV_LOG_ERROR, "header damaged\n");
return -1;
}
- if (s->width != avctx->coded_width || s->height != avctx->coded_height){
- ParseContext pc= s->parse_context; //FIXME move this demuxing hack to libavformat
- s->parse_context.buffer=0;
- MPV_common_end(s);
- s->parse_context= pc;
+ if (s->width != avctx->coded_width || s->height != avctx->coded_height) {
+ ParseContext pc = s->parse_context; // FIXME move this demuxing hack to libavformat
+ s->parse_context.buffer = 0;
+ ff_mpv_common_end(s);
+ s->parse_context = pc;
}
+
if (!s->context_initialized) {
- avcodec_set_dimensions(avctx, s->width, s->height);
+ if ((ret = ff_mpv_common_init(s)) < 0)
+ return ret;
+
+ ret = ff_set_dimensions(avctx, s->width, s->height);
+ if (ret < 0)
+ return ret;
goto retry;
}
- // for hurry_up==5
- s->current_picture.pict_type= s->pict_type;
- s->current_picture.key_frame= s->pict_type == FF_I_TYPE;
+ // for skipping the frame
+ s->current_picture.f->pict_type = s->pict_type;
+ s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;
- /* skip everything if we are in a hurry>=5 */
- if(avctx->hurry_up>=5) return get_consumed_bytes(s, buf_size);
- if( (avctx->skip_frame >= AVDISCARD_NONREF && s->pict_type==FF_B_TYPE)
- ||(avctx->skip_frame >= AVDISCARD_NONKEY && s->pict_type!=FF_I_TYPE)
- || avctx->skip_frame >= AVDISCARD_ALL)
+ if ((avctx->skip_frame >= AVDISCARD_NONREF && s->pict_type == AV_PICTURE_TYPE_B) ||
+ (avctx->skip_frame >= AVDISCARD_NONKEY && s->pict_type != AV_PICTURE_TYPE_I) ||
+ avctx->skip_frame >= AVDISCARD_ALL)
return get_consumed_bytes(s, buf_size);
- if(MPV_frame_start(s, avctx) < 0)
+ if (ff_mpv_frame_start(s, avctx) < 0)
return -1;
- ff_er_frame_start(s);
+ ff_mpeg_er_frame_start(s);
/* decode each macroblock */
- s->mb_x=0;
- s->mb_y=0;
+ s->mb_x = 0;
+ s->mb_y = 0;
- while(h->gob_number < (s->mb_height==18 ? 12 : 5)){
- if(ff_h261_resync(h)<0)
+ while (h->gob_number < (s->mb_height == 18 ? 12 : 5)) {
+ if (h261_resync(h) < 0)
break;
h261_decode_gob(h);
}
- MPV_frame_end(s);
+ ff_mpv_frame_end(s);
+
+ assert(s->current_picture.f->pict_type == s->current_picture_ptr->f->pict_type);
+ assert(s->current_picture.f->pict_type == s->pict_type);
-assert(s->current_picture.pict_type == s->current_picture_ptr->pict_type);
-assert(s->current_picture.pict_type == s->pict_type);
- *pict= *(AVFrame*)s->current_picture_ptr;
- ff_print_debug_info(s, pict);
+ if ((ret = av_frame_ref(pict, s->current_picture_ptr->f)) < 0)
+ return ret;
+ ff_print_debug_info(s, s->current_picture_ptr);
- *data_size = sizeof(AVFrame);
+ *got_frame = 1;
return get_consumed_bytes(s, buf_size);
}
static av_cold int h261_decode_end(AVCodecContext *avctx)
{
- H261Context *h= avctx->priv_data;
+ H261Context *h = avctx->priv_data;
MpegEncContext *s = &h->s;
- MPV_common_end(s);
+ ff_mpv_common_end(s);
return 0;
}
-AVCodec h261_decoder = {
- "h261",
- CODEC_TYPE_VIDEO,
- CODEC_ID_H261,
- sizeof(H261Context),
- h261_decode_init,
- NULL,
- h261_decode_end,
- h261_decode_frame,
- CODEC_CAP_DR1,
- .long_name = NULL_IF_CONFIG_SMALL("H.261"),
+AVCodec ff_h261_decoder = {
+ .name = "h261",
+ .long_name = NULL_IF_CONFIG_SMALL("H.261"),
+ .type = AVMEDIA_TYPE_VIDEO,
+ .id = AV_CODEC_ID_H261,
+ .priv_data_size = sizeof(H261Context),
+ .init = h261_decode_init,
+ .close = h261_decode_end,
+ .decode = h261_decode_frame,
+ .capabilities = AV_CODEC_CAP_DR1,
};
projects / ffmpeg / blobdiff