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/*
* FLV decoding.
*
* This file is part of FFmpeg.
*
* 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.
*
* 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 FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavutil/imgutils.h"
#include "flv.h"
#include "h263dec.h"
#include "mpegvideo.h"
#include "mpegvideodata.h"
int ff_flv_decode_picture_header(MpegEncContext *s)
{
int format, width, height;
/* picture header */
if (get_bits(&s->gb, 17) != 1) {
av_log(s->avctx, AV_LOG_ERROR, "Bad picture start code\n");
return AVERROR_INVALIDDATA;
}
format = get_bits(&s->gb, 5);
if (format != 0 && format != 1) {
av_log(s->avctx, AV_LOG_ERROR, "Bad picture format\n");
return AVERROR_INVALIDDATA;
}
s->h263_flv = format + 1;
s->picture_number = get_bits(&s->gb, 8); /* picture timestamp */
format = get_bits(&s->gb, 3);
switch (format) {
case 0:
width = get_bits(&s->gb, 8);
height = get_bits(&s->gb, 8);
break;
case 1:
width = get_bits(&s->gb, 16);
height = get_bits(&s->gb, 16);
break;
case 2:
width = 352;
height = 288;
break;
case 3:
width = 176;
height = 144;
break;
case 4:
width = 128;
height = 96;
break;
case 5:
width = 320;
height = 240;
break;
case 6:
width = 160;
height = 120;
break;
default:
width = height = 0;
break;
}
if (av_image_check_size(width, height, 0, s->avctx))
return AVERROR(EINVAL);
s->width = width;
s->height = height;
s->pict_type = AV_PICTURE_TYPE_I + get_bits(&s->gb, 2);
s->droppable = s->pict_type > AV_PICTURE_TYPE_P;
if (s->droppable)
s->pict_type = AV_PICTURE_TYPE_P;
skip_bits1(&s->gb); /* deblocking flag */
s->chroma_qscale = s->qscale = get_bits(&s->gb, 5);
s->h263_plus = 0;
s->h263_long_vectors = 0;
/* PEI */
if (skip_1stop_8data_bits(&s->gb) < 0)
return AVERROR_INVALIDDATA;
s->f_code = 1;
if (s->ehc_mode)
s->avctx->sample_aspect_ratio= (AVRational){1,2};
if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
av_log(s->avctx, AV_LOG_DEBUG, "%c esc_type:%d, qp:%d num:%d\n",
s->droppable ? 'D' : av_get_picture_type_char(s->pict_type),
s->h263_flv - 1, s->qscale, s->picture_number);
}
s->y_dc_scale_table = s->c_dc_scale_table = ff_mpeg1_dc_scale_table;
return 0;
}
const AVCodec ff_flv_decoder = {
.name = "flv",
.long_name = NULL_IF_CONFIG_SMALL("FLV / Sorenson Spark / Sorenson H.263 (Flash Video)"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_FLV1,
.priv_data_size = sizeof(MpegEncContext),
.init = ff_h263_decode_init,
.close = ff_h263_decode_end,
.decode = ff_h263_decode_frame,
.capabilities = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1,
.caps_internal = FF_CODEC_CAP_SKIP_FRAME_FILL_PARAM,
.max_lowres = 3,
.pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUV420P,
AV_PIX_FMT_NONE },
};
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