/*

  * 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 "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%08x\n", crc->crcval);

     avio_write(s->pb, buf, strlen(buf));

     avio_flush(s->pb);

     return 0;
 }
 

 AVOutputFormat ff_crc_muxer = {

     "crc",

     NULL_IF_CONFIG_SMALL("CRC testing format"),

     NULL,
     "",

     sizeof(CRCState),

     CODEC_ID_PCM_S16LE,
     CODEC_ID_RAWVIDEO,
     crc_write_header,
     crc_write_packet,
     crc_write_trailer,
 };