* 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
*/
* H.261 decoder.
*/
+#include "libavutil/avassert.h"
#include "avcodec.h"
#include "mpeg_er.h"
#include "mpegutils.h"
// 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);
}
/* GEI */
- while (get_bits1(&s->gb) != 0)
- skip_bits(&s->gb, 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;
}
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;
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 = 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) {
+ 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 = get_bits(&s->gb, 6);
- level = get_sbits(&s->gb, 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 (get_bits1(&s->gb))
+ 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;
}
// Read mtype
h->mtype = get_vlc2(&s->gb, h261_mtype_vlc.table, H261_MTYPE_VLC_BITS, 2);
- if (h->mtype < 0 || h->mtype >= FF_ARRAY_ELEMS(ff_h261_mtype_map)) {
+ 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
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)) {
skip_bits1(&s->gb); /* Reserved */
/* PEI */
- while (get_bits1(&s->gb) != 0)
- skip_bits(&s->gb, 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
s->parse_context = pc;
}
- if (!s->context_initialized)
+ if (!s->context_initialized) {
if ((ret = ff_mpv_common_init(s)) < 0)
return ret;
- if (!s->context_initialized) {
ret = ff_set_dimensions(avctx, s->width, s->height);
if (ret < 0)
return ret;
}
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;
.close = h261_decode_end,
.decode = h261_decode_frame,
.capabilities = CODEC_CAP_DR1,
+ .max_lowres = 3,
};