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 "mpegvideo.h"
24 /* don't understand why they choose a different header ! */
25 int ff_intel_h263_decode_picture_header(MpegEncContext *s)
29 if (get_bits_left(&s->gb) == 64) { /* special dummy frames */
34 if (get_bits_long(&s->gb, 22) != 0x20) {
35 av_log(s->avctx, AV_LOG_ERROR, "Bad picture start code\n");
38 s->picture_number = get_bits(&s->gb, 8); /* picture timestamp */
40 if (check_marker(&s->gb, "after picture_number") != 1) {
41 return -1; /* marker */
43 if (get_bits1(&s->gb) != 0) {
44 av_log(s->avctx, AV_LOG_ERROR, "Bad H263 id\n");
45 return -1; /* h263 id */
47 skip_bits1(&s->gb); /* split screen off */
48 skip_bits1(&s->gb); /* camera off */
49 skip_bits1(&s->gb); /* freeze picture release off */
51 format = get_bits(&s->gb, 3);
52 if (format == 0 || format == 6) {
53 av_log(s->avctx, AV_LOG_ERROR, "Intel H263 free format not supported\n");
58 s->pict_type = AV_PICTURE_TYPE_I + get_bits1(&s->gb);
60 s->h263_long_vectors = get_bits1(&s->gb);
62 if (get_bits1(&s->gb) != 0) {
63 av_log(s->avctx, AV_LOG_ERROR, "SAC not supported\n");
64 return -1; /* SAC: off */
66 s->obmc= get_bits1(&s->gb);
67 s->unrestricted_mv = s->obmc || s->h263_long_vectors;
68 s->pb_frame = get_bits1(&s->gb);
71 s->width = ff_h263_format[format][0];
72 s->height = ff_h263_format[format][1];
73 s->avctx->sample_aspect_ratio.num = 12;
74 s->avctx->sample_aspect_ratio.den = 11;
76 format = get_bits(&s->gb, 3);
77 if(format == 0 || format == 7){
78 av_log(s->avctx, AV_LOG_ERROR, "Wrong Intel H263 format\n");
81 if(get_bits(&s->gb, 2))
82 av_log(s->avctx, AV_LOG_ERROR, "Bad value for reserved field\n");
83 s->loop_filter = get_bits1(&s->gb) * !s->avctx->lowres;
85 av_log(s->avctx, AV_LOG_ERROR, "Bad value for reserved field\n");
88 if(get_bits(&s->gb, 5))
89 av_log(s->avctx, AV_LOG_ERROR, "Bad value for reserved field\n");
90 if(get_bits(&s->gb, 5) != 1)
91 av_log(s->avctx, AV_LOG_ERROR, "Invalid marker\n");
94 int ar = get_bits(&s->gb, 4);
95 skip_bits(&s->gb, 9); // display width
96 check_marker(&s->gb, "in dimensions");
97 skip_bits(&s->gb, 9); // display height
99 s->avctx->sample_aspect_ratio.num = get_bits(&s->gb, 8); // aspect ratio - width
100 s->avctx->sample_aspect_ratio.den = get_bits(&s->gb, 8); // aspect ratio - height
102 s->avctx->sample_aspect_ratio = ff_h263_pixel_aspect[ar];
104 if (s->avctx->sample_aspect_ratio.num == 0)
105 av_log(s->avctx, AV_LOG_ERROR, "Invalid aspect ratio.\n");
108 s->chroma_qscale= s->qscale = get_bits(&s->gb, 5);
109 skip_bits1(&s->gb); /* Continuous Presence Multipoint mode: off */
112 skip_bits(&s->gb, 3); //temporal reference for B-frame
113 skip_bits(&s->gb, 2); //dbquant
117 if (skip_1stop_8data_bits(&s->gb) < 0)
118 return AVERROR_INVALIDDATA;
122 s->c_dc_scale_table= ff_mpeg1_dc_scale_table;
124 ff_h263_show_pict_info(s);
129 AVCodec ff_h263i_decoder = {
131 .long_name = NULL_IF_CONFIG_SMALL("Intel H.263"),
132 .type = AVMEDIA_TYPE_VIDEO,
133 .id = AV_CODEC_ID_H263I,
134 .priv_data_size = sizeof(MpegEncContext),
135 .init = ff_h263_decode_init,
136 .close = ff_h263_decode_end,
137 .decode = ff_h263_decode_frame,
138 .capabilities = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
139 .pix_fmts = (const enum AVPixelFormat[]) {