FFmpeg
crc.c
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1 /*
2  * This file is part of FFmpeg.
3  *
4  * FFmpeg is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * FFmpeg is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with FFmpeg; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 #include <stdint.h>
20 #include <stdio.h>
21 
22 #include "libavutil/crc.h"
23 
24 int main(void)
25 {
26  uint8_t buf[1999];
27  int i;
28  static const unsigned p[7][3] = {
29  { AV_CRC_32_IEEE_LE, 0xEDB88320, 0x3D5CDD04 },
30  { AV_CRC_32_IEEE , 0x04C11DB7, 0xC0F5BAE0 },
31  { AV_CRC_24_IEEE , 0x864CFB , 0xB704CE },
32  { AV_CRC_16_ANSI_LE, 0xA001 , 0xBFD8 },
33  { AV_CRC_16_ANSI , 0x8005 , 0x1FBB },
34  { AV_CRC_8_ATM , 0x07 , 0xE3 },
35  { AV_CRC_8_EBU , 0x1D , 0xD6 },
36  };
37  const AVCRC *ctx;
38 
39  for (i = 0; i < sizeof(buf); i++)
40  buf[i] = i + i * i;
41 
42  for (i = 0; i < 7; i++) {
43  ctx = av_crc_get_table(p[i][0]);
44  printf("crc %08X = %X\n", p[i][1], av_crc(ctx, 0, buf, sizeof(buf)));
45  }
46  return 0;
47 }
AV_CRC_8_EBU
@ AV_CRC_8_EBU
Definition: crc.h:56
AVCRC
uint32_t AVCRC
Definition: crc.h:46
AV_CRC_24_IEEE
@ AV_CRC_24_IEEE
Definition: crc.h:55
crc.h
AV_CRC_16_ANSI_LE
@ AV_CRC_16_ANSI_LE
Definition: crc.h:54
ctx
AVFormatContext * ctx
Definition: movenc.c:48
AV_CRC_16_ANSI
@ AV_CRC_16_ANSI
Definition: crc.h:50
printf
printf("static const uint8_t my_array[100] = {\n")
av_crc_get_table
const AVCRC * av_crc_get_table(AVCRCId crc_id)
Get an initialized standard CRC table.
Definition: crc.c:374
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:255
main
int main(void)
Definition: crc.c:24
AV_CRC_32_IEEE
@ AV_CRC_32_IEEE
Definition: crc.h:52
av_crc
uint32_t av_crc(const AVCRC *ctx, uint32_t crc, const uint8_t *buffer, size_t length)
Calculate the CRC of a block.
Definition: crc.c:392
AV_CRC_32_IEEE_LE
@ AV_CRC_32_IEEE_LE
Definition: crc.h:53
AV_CRC_8_ATM
@ AV_CRC_8_ATM
Definition: crc.h:49