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Diffstat (limited to 'libavcodec/h261dec.c')
-rw-r--r--libavcodec/h261dec.c170
1 files changed, 95 insertions, 75 deletions
diff --git a/libavcodec/h261dec.c b/libavcodec/h261dec.c
index b08598ec99..14a874c45d 100644
--- a/libavcodec/h261dec.c
+++ b/libavcodec/h261dec.c
@@ -3,20 +3,20 @@
* Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
* Copyright (c) 2004 Maarten Daniels
*
- * This file is part of Libav.
+ * This file is part of FFmpeg.
*
- * Libav is free software; you can redistribute it and/or
+ * 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.
*
- * Libav is distributed in the hope that it will be useful,
+ * 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 Libav; if not, write to the Free Software
+ * License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
@@ -25,15 +25,14 @@
* H.261 decoder.
*/
+#include "libavutil/avassert.h"
#include "avcodec.h"
-#include "bitstream.h"
#include "mpeg_er.h"
#include "mpegutils.h"
#include "mpegvideo.h"
#include "h263.h"
#include "h261.h"
#include "internal.h"
-#include "vlc.h"
#define H261_MBA_VLC_BITS 9
#define H261_MTYPE_VLC_BITS 6
@@ -77,14 +76,11 @@ static av_cold int h261_decode_init(AVCodecContext *avctx)
// set defaults
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;
+ ff_mpv_decode_init(s, avctx);
+
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);
@@ -105,18 +101,18 @@ static int h261_decode_gob_header(H261Context *h)
if (!h->gob_start_code_skipped) {
/* Check for GOB Start Code */
- val = bitstream_peek(&s->bc, 15);
+ val = show_bits(&s->gb, 15);
if (val)
return -1;
/* We have a GBSC */
- bitstream_skip(&s->bc, 16);
+ skip_bits(&s->gb, 16);
}
h->gob_start_code_skipped = 0;
- h->gob_number = bitstream_read(&s->bc, 4); /* GN */
- s->qscale = bitstream_read(&s->bc, 5); /* GQUANT */
+ h->gob_number = get_bits(&s->gb, 4); /* GN */
+ s->qscale = get_bits(&s->gb, 5); /* GQUANT */
/* Check if gob_number is valid */
if (s->mb_height == 18) { // CIF
@@ -129,12 +125,12 @@ static int h261_decode_gob_header(H261Context *h)
}
/* GEI */
- while (bitstream_read_bit(&s->bc) != 0)
- bitstream_skip(&s->bc, 8);
+ if (skip_1stop_8data_bits(&s->gb) < 0)
+ return AVERROR_INVALIDDATA;
if (s->qscale == 0) {
av_log(s->avctx, AV_LOG_ERROR, "qscale has forbidden 0 value\n");
- if (s->avctx->err_recognition & AV_EF_BITSTREAM)
+ if (s->avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_COMPLIANT))
return -1;
}
@@ -162,27 +158,27 @@ static int h261_resync(H261Context *h)
if (ret >= 0)
return 0;
} else {
- if (bitstream_peek(&s->bc, 15) == 0) {
+ 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->bc = s->last_resync_bc;
- bitstream_align(&s->bc);
- left = bitstream_bits_left(&s->bc);
+ s->gb = s->last_resync_gb;
+ align_get_bits(&s->gb);
+ left = get_bits_left(&s->gb);
for (; left > 15 + 1 + 4 + 5; left -= 8) {
- if (bitstream_peek(&s->bc, 15) == 0) {
- BitstreamContext bak = s->bc;
+ if (show_bits(&s->gb, 15) == 0) {
+ GetBitContext bak = s->gb;
ret = h261_decode_gob_header(h);
if (ret >= 0)
return 0;
- s->bc = bak;
+ s->gb = bak;
}
- bitstream_skip(&s->bc, 8);
+ skip_bits(&s->gb, 8);
}
}
@@ -220,7 +216,14 @@ static int h261_decode_mb_skipped(H261Context *h, int mba1, int mba2)
s->mb_skipped = 1;
h->mtype &= ~MB_TYPE_H261_FIL;
- ff_mpv_decode_mb(s, s->block);
+ if (s->current_picture.motion_val[0]) {
+ int b_stride = 2*s->mb_width + 1;
+ int b_xy = 2 * s->mb_x + (2 * s->mb_y) * b_stride;
+ s->current_picture.motion_val[0][b_xy][0] = s->mv[0][0][0];
+ s->current_picture.motion_val[0][b_xy][1] = s->mv[0][0][1];
+ }
+
+ ff_mpv_reconstruct_mb(s, s->block);
}
return 0;
@@ -230,9 +233,9 @@ 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(BitstreamContext *bc, int v)
+static int decode_mv_component(GetBitContext *gb, int v)
{
- int mv_diff = bitstream_read_vlc(bc, h261_mv_vlc.table, H261_MV_VLC_BITS, 2);
+ 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)
@@ -240,7 +243,7 @@ static int decode_mv_component(BitstreamContext *bc, int v)
mv_diff = mvmap[mv_diff];
- if (mv_diff && !bitstream_read_bit(bc))
+ if (mv_diff && !get_bits1(gb))
mv_diff = -mv_diff;
v += mv_diff;
@@ -259,7 +262,7 @@ static int decode_mv_component(BitstreamContext *bc, int v)
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;
+ int level, i, j, run;
RLTable *rl = &ff_h261_rl_tcoeff;
const uint8_t *scan_table;
@@ -272,7 +275,7 @@ static int h261_decode_block(H261Context *h, int16_t *block, int n, int coded)
scan_table = s->intra_scantable.permutated;
if (s->mb_intra) {
/* DC coef */
- level = bitstream_read(&s->bc, 8);
+ 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",
@@ -290,10 +293,10 @@ static int h261_decode_block(H261Context *h, int16_t *block, int n, int coded)
// EOB Not possible for first level when cbp is available (that's why the table is different)
// 0 1 1s
// * * 0*
- int check = bitstream_peek(&s->bc, 2);
+ int check = show_bits(&s->gb, 2);
i = 0;
if (check & 0x2) {
- bitstream_skip(&s->bc, 2);
+ skip_bits(&s->gb, 2);
block[0] = (check & 0x1) ? -1 : 1;
i = 1;
}
@@ -304,39 +307,47 @@ static int h261_decode_block(H261Context *h, int16_t *block, int n, int coded)
s->block_last_index[n] = i - 1;
return 0;
}
+ {
+ OPEN_READER(re, &s->gb);
+ i--; // offset by -1 to allow direct indexing of scan_table
for (;;) {
- code = bitstream_read_vlc(&s->bc, 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) {
+ UPDATE_CACHE(re, &s->gb);
+ GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TCOEFF_VLC_BITS, 2, 0);
+ if (run == 66) {
+ if (level) {
+ CLOSE_READER(re, &s->gb);
+ av_log(s->avctx, AV_LOG_ERROR, "illegal ac vlc code at %dx%d\n",
+ s->mb_x, s->mb_y);
+ return -1;
+ }
/* 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 = bitstream_read(&s->bc, 6);
- level = bitstream_read_signed(&s->bc, 8);
- } else if (code == 0) {
+ run = SHOW_UBITS(re, &s->gb, 6) + 1;
+ SKIP_CACHE(re, &s->gb, 6);
+ level = SHOW_SBITS(re, &s->gb, 8);
+ SKIP_COUNTER(re, &s->gb, 6 + 8);
+ } else if (level == 0) {
break;
} else {
- run = rl->table_run[code];
- level = rl->table_level[code];
- if (bitstream_read_bit(&s->bc))
+ if (SHOW_UBITS(re, &s->gb, 1))
level = -level;
+ SKIP_COUNTER(re, &s->gb, 1);
}
i += run;
if (i >= 64) {
+ CLOSE_READER(re, &s->gb);
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;
+ CLOSE_READER(re, &s->gb);
+ }
+ s->block_last_index[n] = i;
return 0;
}
@@ -348,8 +359,8 @@ static int h261_decode_mb(H261Context *h)
cbp = 63;
// Read mba
do {
- h->mba_diff = bitstream_read_vlc(&s->bc, h261_mba_vlc.table,
- H261_MBA_VLC_BITS, 2);
+ 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 */
@@ -360,7 +371,7 @@ static int h261_decode_mb(H261Context *h)
} while (h->mba_diff == MBA_STUFFING); // stuffing
if (h->mba_diff < 0) {
- if (bitstream_bits_left(&s->bc) <= 7)
+ 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);
@@ -380,17 +391,18 @@ static int h261_decode_mb(H261Context *h)
ff_update_block_index(s);
// Read mtype
- h->mtype = bitstream_read_vlc(&s->bc, h261_mtype_vlc.table, H261_MTYPE_VLC_BITS, 2);
- if (h->mtype < 0 || h->mtype >= FF_ARRAY_ELEMS(ff_h261_mtype_map)) {
+ h->mtype = get_vlc2(&s->gb, h261_mtype_vlc.table, H261_MTYPE_VLC_BITS, 2);
+ if (h->mtype < 0) {
av_log(s->avctx, AV_LOG_ERROR, "Invalid mtype index %d\n",
h->mtype);
return SLICE_ERROR;
}
+ av_assert0(h->mtype < FF_ARRAY_ELEMS(ff_h261_mtype_map));
h->mtype = ff_h261_mtype_map[h->mtype];
// Read mquant
if (IS_QUANT(h->mtype))
- ff_set_qscale(s, bitstream_read(&s->bc, 5));
+ ff_set_qscale(s, get_bits(&s->gb, 5));
s->mb_intra = IS_INTRA4x4(h->mtype);
@@ -410,8 +422,8 @@ static int h261_decode_mb(H261Context *h)
h->current_mv_y = 0;
}
- h->current_mv_x = decode_mv_component(&s->bc, h->current_mv_x);
- h->current_mv_y = decode_mv_component(&s->bc, h->current_mv_y);
+ 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;
@@ -419,7 +431,7 @@ static int h261_decode_mb(H261Context *h)
// Read cbp
if (HAS_CBP(h->mtype))
- cbp = bitstream_read_vlc(&s->bc, h261_cbp_vlc.table, H261_CBP_VLC_BITS, 2) + 1;
+ 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;
@@ -433,6 +445,13 @@ static int h261_decode_mb(H261Context *h)
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;
+ if (s->current_picture.motion_val[0]) {
+ int b_stride = 2*s->mb_width + 1;
+ int b_xy = 2 * s->mb_x + (2 * s->mb_y) * b_stride;
+ s->current_picture.motion_val[0][b_xy][0] = s->mv[0][0][0];
+ s->current_picture.motion_val[0][b_xy][1] = s->mv[0][0][1];
+ }
+
intra:
/* decode each block */
if (s->mb_intra || HAS_CBP(h->mtype)) {
@@ -447,7 +466,7 @@ intra:
s->block_last_index[i] = -1;
}
- ff_mpv_decode_mb(s, s->block);
+ ff_mpv_reconstruct_mb(s, s->block);
return SLICE_OK;
}
@@ -462,8 +481,8 @@ static int h261_decode_picture_header(H261Context *h)
int format, i;
uint32_t startcode = 0;
- for (i = bitstream_bits_left(&s->bc); i > 24; i -= 1) {
- startcode = ((startcode << 1) | bitstream_read(&s->bc, 1)) & 0x000FFFFF;
+ for (i = get_bits_left(&s->gb); i > 24; i -= 1) {
+ startcode = ((startcode << 1) | get_bits(&s->gb, 1)) & 0x000FFFFF;
if (startcode == 0x10)
break;
@@ -475,7 +494,7 @@ static int h261_decode_picture_header(H261Context *h)
}
/* temporal reference */
- i = bitstream_read(&s->bc, 5); /* picture timestamp */
+ i = get_bits(&s->gb, 5); /* picture timestamp */
if (i < (s->picture_number & 31))
i += 32;
s->picture_number = (s->picture_number & ~31) + i;
@@ -483,11 +502,11 @@ static int h261_decode_picture_header(H261Context *h)
s->avctx->framerate = (AVRational) { 30000, 1001 };
/* PTYPE starts here */
- bitstream_skip(&s->bc, 1); /* split screen off */
- bitstream_skip(&s->bc, 1); /* camera off */
- bitstream_skip(&s->bc, 1); /* freeze picture release off */
+ skip_bits1(&s->gb); /* split screen off */
+ skip_bits1(&s->gb); /* camera off */
+ skip_bits1(&s->gb); /* freeze picture release off */
- format = bitstream_read_bit(&s->bc);
+ format = get_bits1(&s->gb);
// only 2 formats possible
if (format == 0) { // QCIF
@@ -504,12 +523,12 @@ static int h261_decode_picture_header(H261Context *h)
s->mb_num = s->mb_width * s->mb_height;
- bitstream_skip(&s->bc, 1); /* still image mode off */
- bitstream_skip(&s->bc, 1); /* Reserved */
+ skip_bits1(&s->gb); /* still image mode off */
+ skip_bits1(&s->gb); /* Reserved */
/* PEI */
- while (bitstream_read_bit(&s->bc) != 0)
- bitstream_skip(&s->bc, 8);
+ if (skip_1stop_8data_bits(&s->gb) < 0)
+ return AVERROR_INVALIDDATA;
/* 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
@@ -554,7 +573,7 @@ static int h261_decode_gob(H261Context *h)
*/
static int get_consumed_bytes(MpegEncContext *s, int buf_size)
{
- int pos = bitstream_tell(&s->bc) >> 3;
+ 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)
@@ -579,7 +598,7 @@ static int h261_decode_frame(AVCodecContext *avctx, void *data,
h->gob_start_code_skipped = 0;
retry:
- bitstream_init8(&s->bc, buf, buf_size);
+ init_get_bits(&s->gb, buf, buf_size * 8);
if (!s->context_initialized)
// we need the IDCT permutation for reading a custom matrix
@@ -636,12 +655,12 @@ retry:
}
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);
+ av_assert0(s->current_picture.f->pict_type == s->current_picture_ptr->f->pict_type);
+ av_assert0(s->current_picture.f->pict_type == s->pict_type);
if ((ret = av_frame_ref(pict, s->current_picture_ptr->f)) < 0)
return ret;
- ff_print_debug_info(s, s->current_picture_ptr);
+ ff_print_debug_info(s, s->current_picture_ptr, pict);
*got_frame = 1;
@@ -667,4 +686,5 @@ AVCodec ff_h261_decoder = {
.close = h261_decode_end,
.decode = h261_decode_frame,
.capabilities = AV_CODEC_CAP_DR1,
+ .max_lowres = 3,
};
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-14 19:26:56 +0000