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rangecoder.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 <string.h>
21 
22 #include "libavutil/lfg.h"
23 #include "libavutil/log.h"
24 
25 #include "libavcodec/rangecoder.h"
26 
27 #define SIZE 10240
28 
29 int main(void)
30 {
31  RangeCoder c;
32  uint8_t b[9 * SIZE];
33  uint8_t r[9 * SIZE];
34  int i;
35  uint8_t state[10];
36  AVLFG prng;
37 
38  av_lfg_init(&prng, 1);
39 
41  ff_build_rac_states(&c, (1LL << 32) / 20, 128 + 64 + 32 + 16);
42 
43  memset(state, 128, sizeof(state));
44 
45  for (i = 0; i < SIZE; i++)
46  r[i] = av_lfg_get(&prng) % 7;
47 
48  for (i = 0; i < SIZE; i++)
49  put_rac(&c, state, r[i] & 1);
50 
51  ff_rac_terminate(&c);
52 
53  ff_init_range_decoder(&c, b, SIZE);
54 
55  memset(state, 128, sizeof(state));
56 
57  for (i = 0; i < SIZE; i++)
58  if ((r[i] & 1) != get_rac(&c, state)) {
59  av_log(NULL, AV_LOG_ERROR, "rac failure at %d\n", i);
60  return 1;
61  }
62 
63  return 0;
64 }
Definition: lfg.h:27
#define NULL
Definition: coverity.c:32
int main(void)
Definition: rangecoder.c:29
Range coder.
const char * b
Definition: vf_curves.c:113
int ff_rac_terminate(RangeCoder *c)
Definition: rangecoder.c:109
uint8_t
static int get_rac(RangeCoder *c, uint8_t *const state)
Definition: rangecoder.h:119
static struct @281 state
#define av_log(a,...)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
const char * r
Definition: vf_curves.c:111
void ff_build_rac_states(RangeCoder *c, int factor, int max_p)
Definition: rangecoder.c:68
static unsigned int av_lfg_get(AVLFG *c)
Get the next random unsigned 32-bit number using an ALFG.
Definition: lfg.h:47
av_cold void ff_init_range_encoder(RangeCoder *c, uint8_t *buf, int buf_size)
Definition: rangecoder.c:42
av_cold void ff_init_range_decoder(RangeCoder *c, const uint8_t *buf, int buf_size)
Definition: rangecoder.c:53
#define SIZE
Definition: rangecoder.c:27
av_cold void av_lfg_init(AVLFG *c, unsigned int seed)
Definition: lfg.c:32
static double c[64]
#define put_rac(C, S, B)