1
0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-02 03:06:28 +02:00
FFmpeg/libavcodec/atsc_a53.c
Andreas Rheinhardt 790f793844 avutil/common: Don't auto-include mem.h
There are lots of files that don't need it: The number of object
files that actually need it went down from 2011 to 884 here.

Keep it for external users in order to not cause breakages.

Also improve the other headers a bit while just at it.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2024-03-31 00:08:43 +01:00

121 lines
3.3 KiB
C

/*
* 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 <stddef.h>
#include <stdint.h>
#include "libavutil/mem.h"
#include "atsc_a53.h"
#include "get_bits.h"
int ff_alloc_a53_sei(const AVFrame *frame, size_t prefix_len,
void **data, size_t *sei_size)
{
AVFrameSideData *side_data = NULL;
uint8_t *sei_data;
if (frame)
side_data = av_frame_get_side_data(frame, AV_FRAME_DATA_A53_CC);
if (!side_data) {
*data = NULL;
return 0;
}
*sei_size = side_data->size + 11;
*data = av_mallocz(*sei_size + prefix_len);
if (!*data)
return AVERROR(ENOMEM);
sei_data = (uint8_t*)*data + prefix_len;
// country code
sei_data[0] = 181;
sei_data[1] = 0;
sei_data[2] = 49;
/**
* 'GA94' is standard in North America for ATSC, but hard coding
* this style may not be the right thing to do -- other formats
* do exist. This information is not available in the side_data
* so we are going with this right now.
*/
AV_WL32(sei_data + 3, MKTAG('G', 'A', '9', '4'));
sei_data[7] = 3;
sei_data[8] = ((side_data->size/3) & 0x1f) | 0x40;
sei_data[9] = 0;
memcpy(sei_data + 10, side_data->data, side_data->size);
sei_data[side_data->size+10] = 255;
return 0;
}
int ff_parse_a53_cc(AVBufferRef **pbuf, const uint8_t *data, int size)
{
AVBufferRef *buf = *pbuf;
GetBitContext gb;
size_t new_size, old_size = buf ? buf->size : 0;
int ret, cc_count;
if (size < 3)
return AVERROR_INVALIDDATA;
ret = init_get_bits8(&gb, data, size);
if (ret < 0)
return ret;
if (get_bits(&gb, 8) != 0x3) // user_data_type_code
return 0;
skip_bits(&gb, 1); // reserved
if (!get_bits(&gb, 1)) // process_cc_data_flag
return 0;
skip_bits(&gb, 1); // zero bit
cc_count = get_bits(&gb, 5);
if (!cc_count)
return 0;
skip_bits(&gb, 8); // reserved
/* 3 bytes per CC plus one byte marker_bits at the end */
if (cc_count * 3 >= (get_bits_left(&gb) >> 3))
return AVERROR_INVALIDDATA;
new_size = (old_size + cc_count * 3);
if (new_size > INT_MAX)
return AVERROR_INVALIDDATA;
/* Allow merging of the cc data from two fields. */
ret = av_buffer_realloc(pbuf, new_size);
if (ret < 0)
return ret;
buf = *pbuf;
/* Use of av_buffer_realloc assumes buffer is writeable */
for (int i = 0; i < cc_count; i++) {
buf->data[old_size++] = get_bits(&gb, 8);
buf->data[old_size++] = get_bits(&gb, 8);
buf->data[old_size++] = get_bits(&gb, 8);
}
return cc_count;
}