FFmpeg4/libavformat/crcenc.c

70 lines
2.0 KiB
C

/*
* CRC encoder (for codec/format testing)
* Copyright (c) 2002 Fabrice Bellard
*
* 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 <inttypes.h>
#include "libavutil/adler32.h"
#include "avformat.h"
typedef struct CRCState {
uint32_t crcval;
} CRCState;
static int crc_write_header(struct AVFormatContext *s)
{
CRCState *crc = s->priv_data;
/* init CRC */
crc->crcval = 1;
return 0;
}
static int crc_write_packet(struct AVFormatContext *s, AVPacket *pkt)
{
CRCState *crc = s->priv_data;
crc->crcval = av_adler32_update(crc->crcval, pkt->data, pkt->size);
return 0;
}
static int crc_write_trailer(struct AVFormatContext *s)
{
CRCState *crc = s->priv_data;
char buf[64];
snprintf(buf, sizeof(buf), "CRC=0x%08"PRIx32"\n", crc->crcval);
avio_write(s->pb, buf, strlen(buf));
return 0;
}
AVOutputFormat ff_crc_muxer = {
.name = "crc",
.long_name = NULL_IF_CONFIG_SMALL("CRC testing"),
.priv_data_size = sizeof(CRCState),
.audio_codec = AV_CODEC_ID_PCM_S16LE,
.video_codec = AV_CODEC_ID_RAWVIDEO,
.write_header = crc_write_header,
.write_packet = crc_write_packet,
.write_trailer = crc_write_trailer,
.flags = AVFMT_NOTIMESTAMPS,
};