4 * This file is part of FFmpeg.
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 #include "libavutil/imgutils.h"
25 #include "mpegvideo.h"
27 int ff_flv_decode_picture_header(MpegEncContext *s)
29 int format, width, height;
32 if (get_bits_long(&s->gb, 17) != 1) {
33 av_log(s->avctx, AV_LOG_ERROR, "Bad picture start code\n");
34 return AVERROR_INVALIDDATA;
36 format = get_bits(&s->gb, 5);
37 if (format != 0 && format != 1) {
38 av_log(s->avctx, AV_LOG_ERROR, "Bad picture format\n");
39 return AVERROR_INVALIDDATA;
41 s->h263_flv = format + 1;
42 s->picture_number = get_bits(&s->gb, 8); /* picture timestamp */
43 format = get_bits(&s->gb, 3);
46 width = get_bits(&s->gb, 8);
47 height = get_bits(&s->gb, 8);
50 width = get_bits(&s->gb, 16);
51 height = get_bits(&s->gb, 16);
77 if (av_image_check_size(width, height, 0, s->avctx))
78 return AVERROR(EINVAL);
82 s->pict_type = AV_PICTURE_TYPE_I + get_bits(&s->gb, 2);
83 s->droppable = s->pict_type > AV_PICTURE_TYPE_P;
85 s->pict_type = AV_PICTURE_TYPE_P;
87 skip_bits1(&s->gb); /* deblocking flag */
88 s->chroma_qscale = s->qscale = get_bits(&s->gb, 5);
92 s->unrestricted_mv = 1;
93 s->h263_long_vectors = 0;
96 if (skip_1stop_8data_bits(&s->gb) < 0)
97 return AVERROR_INVALIDDATA;
102 s->avctx->sample_aspect_ratio= (AVRational){1,2};
104 if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
105 av_log(s->avctx, AV_LOG_DEBUG, "%c esc_type:%d, qp:%d num:%d\n",
106 s->droppable ? 'D' : av_get_picture_type_char(s->pict_type),
107 s->h263_flv - 1, s->qscale, s->picture_number);
110 s->y_dc_scale_table = s->c_dc_scale_table = ff_mpeg1_dc_scale_table;
115 AVCodec ff_flv_decoder = {
117 .long_name = NULL_IF_CONFIG_SMALL("FLV / Sorenson Spark / Sorenson H.263 (Flash Video)"),
118 .type = AVMEDIA_TYPE_VIDEO,
119 .id = AV_CODEC_ID_FLV1,
120 .priv_data_size = sizeof(MpegEncContext),
121 .init = ff_h263_decode_init,
122 .close = ff_h263_decode_end,
123 .decode = ff_h263_decode_frame,
124 .capabilities = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
126 .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUV420P,