1/* 2 * CRC encoder (for codec/format testing) 3 * Copyright (c) 2002 Fabrice Bellard 4 * 5 * This file is part of FFmpeg. 6 * 7 * FFmpeg is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * FFmpeg is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with FFmpeg; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22#include "libavutil/adler32.h" 23#include "avformat.h" 24 25typedef struct CRCState { 26 uint32_t crcval; 27} CRCState; 28 29static int crc_write_header(struct AVFormatContext *s) 30{ 31 CRCState *crc = s->priv_data; 32 33 /* init CRC */ 34 crc->crcval = 1; 35 36 return 0; 37} 38 39static int crc_write_packet(struct AVFormatContext *s, AVPacket *pkt) 40{ 41 CRCState *crc = s->priv_data; 42 crc->crcval = av_adler32_update(crc->crcval, pkt->data, pkt->size); 43 return 0; 44} 45 46static int crc_write_trailer(struct AVFormatContext *s) 47{ 48 CRCState *crc = s->priv_data; 49 char buf[64]; 50 51 snprintf(buf, sizeof(buf), "CRC=0x%08x\n", crc->crcval); 52 put_buffer(s->pb, buf, strlen(buf)); 53 put_flush_packet(s->pb); 54 return 0; 55} 56 57AVOutputFormat crc_muxer = { 58 "crc", 59 NULL_IF_CONFIG_SMALL("CRC testing format"), 60 NULL, 61 "", 62 sizeof(CRCState), 63 CODEC_ID_PCM_S16LE, 64 CODEC_ID_RAWVIDEO, 65 crc_write_header, 66 crc_write_packet, 67 crc_write_trailer, 68}; 69