mirror of https://github.com/FFmpeg/FFmpeg.git
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
63 lines
2.0 KiB
63 lines
2.0 KiB
/* |
|
* Canopus common routines |
|
* Copyright (c) 2015 Vittorio Giovara <vittorio.giovara@gmail.com> |
|
* |
|
* 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 <stdint.h> |
|
|
|
#include "libavutil/rational.h" |
|
|
|
#include "avcodec.h" |
|
#include "bytestream.h" |
|
#include "canopus.h" |
|
|
|
int ff_canopus_parse_info_tag(AVCodecContext *avctx, |
|
const uint8_t *src, size_t size) |
|
{ |
|
GetByteContext gbc; |
|
int par_x, par_y, field_order; |
|
|
|
bytestream2_init(&gbc, src, size); |
|
|
|
/* Parse aspect ratio. */ |
|
bytestream2_skip(&gbc, 8); // unknown, 16 bits 1 |
|
par_x = bytestream2_get_le32(&gbc); |
|
par_y = bytestream2_get_le32(&gbc); |
|
if (par_x && par_y) |
|
av_reduce(&avctx->sample_aspect_ratio.num, |
|
&avctx->sample_aspect_ratio.den, |
|
par_x, par_y, 255); |
|
|
|
/* Short INFO tag (used in CLLC) has only AR data. */ |
|
if (size == 0x18) |
|
return 0; |
|
|
|
bytestream2_skip(&gbc, 16); // unknown RDRT tag |
|
|
|
/* Parse FIEL tag. */ |
|
bytestream2_skip(&gbc, 8); // 'FIEL' and 4 bytes 0 |
|
field_order = bytestream2_get_le32(&gbc); |
|
switch (field_order) { |
|
case 0: avctx->field_order = AV_FIELD_TT; break; |
|
case 1: avctx->field_order = AV_FIELD_BB; break; |
|
case 2: avctx->field_order = AV_FIELD_PROGRESSIVE; break; |
|
} |
|
|
|
return 0; |
|
}
|
|
|