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/*
* FLV decoding.
* This file is part of Libav.
*
* Libav 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,
* 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
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "mpegvideo.h"
#include "h263.h"
#include "flv.h"
#include "libavutil/imgutils.h"
void ff_flv2_decode_ac_esc(GetBitContext *gb, int *level, int *run, int *last){
int is11 = get_bits1(gb);
*last = get_bits1(gb);
*run = get_bits(gb, 6);
if(is11){
*level = get_sbits(gb, 11);
} else {
*level = get_sbits(gb, 7);
}
}
int ff_flv_decode_picture_header(MpegEncContext *s)
{
int format, width, height;
/* picture header */
if (get_bits_long(&s->gb, 17) != 1) {
av_log(s->avctx, AV_LOG_ERROR, "Bad picture start code\n");
return -1;
}
format = get_bits(&s->gb, 5);
if (format != 0 && format != 1) {
av_log(s->avctx, AV_LOG_ERROR, "Bad picture format\n");
return -1;
}
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 -1;
s->width = width;
s->height = height;
s->pict_type = AV_PICTURE_TYPE_I + get_bits(&s->gb, 2);
s->dropable= s->pict_type > AV_PICTURE_TYPE_P;
if (s->dropable)
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->unrestricted_mv = 1;
s->h263_long_vectors = 0;
/* PEI */
while (get_bits1(&s->gb) != 0) {
skip_bits(&s->gb, 8);
}
s->f_code = 1;
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->dropable ? '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;
}
AVCodec ff_flv_decoder = {
.name = "flv",
.type = AVMEDIA_TYPE_VIDEO,
.id = CODEC_ID_FLV1,
.priv_data_size = sizeof(MpegEncContext),
.init = ff_h263_decode_init,
.close = ff_h263_decode_end,
.decode = ff_h263_decode_frame,
.capabilities = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
.max_lowres= 3,
.long_name= NULL_IF_CONFIG_SMALL("Flash Video (FLV) / Sorenson Spark / Sorenson H.263"),
.pix_fmts= ff_pixfmt_list_420,
};
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