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/error.h"
23 #include "libavutil/lfg.h"
24 #include "libavutil/log.h"
25
26 #include "libavcodec/rangecoder.h"
27
28 #define SIZE 1240
29
30 /**
31 * Check if at the current position there is a valid looking termination
32 * @param version version 0 requires the decoder to know the data size in bytes
33 * version 1 needs about 1 bit more space but does not need to
34 * carry the size from encoder to decoder
35 * @returns negative AVERROR code on error or non negative.
36 */
rac_check_termination(RangeCoder *c, int version)37 static int rac_check_termination(RangeCoder *c, int version)
38 {
39 if (version == 1) {
40 RangeCoder tmp = *c;
41 get_rac(c, (uint8_t[]) { 129 });
42
43 if (c->bytestream == tmp.bytestream && c->bytestream > c->bytestream_start)
44 tmp.low -= *--tmp.bytestream;
45 tmp.bytestream_end = tmp.bytestream;
46
47 if (get_rac(&tmp, (uint8_t[]) { 129 }))
48 return AVERROR_INVALIDDATA;
49 } else {
50 if (c->bytestream_end != c->bytestream)
51 return AVERROR_INVALIDDATA;
52 }
53 return 0;
54 }
55
main(void)56 int main(void)
57 {
58 RangeCoder c;
59 uint8_t b[9 * SIZE] = {0};
60 uint8_t r[9 * SIZE];
61 int i, p, actual_length, version;
62 uint8_t state[10];
63 AVLFG prng;
64
65 av_lfg_init(&prng, 1);
66 for (version = 0; version < 2; version++) {
67 for (p = 0; p< 1024; p++) {
68 ff_init_range_encoder(&c, b, SIZE);
69 ff_build_rac_states(&c, (1LL << 32) / 20, 128 + 64 + 32 + 16);
70
71 memset(state, 128, sizeof(state));
72
73 for (i = 0; i < SIZE; i++)
74 r[i] = av_lfg_get(&prng) % 7;
75
76 for (i = 0; i < SIZE; i++)
77 put_rac(&c, state, r[i] & 1);
78
79 actual_length = ff_rac_terminate(&c, version);
80
81 ff_init_range_decoder(&c, b, version ? SIZE : actual_length);
82
83 memset(state, 128, sizeof(state));
84
85 for (i = 0; i < SIZE; i++)
86 if ((r[i] & 1) != get_rac(&c, state)) {
87 av_log(NULL, AV_LOG_ERROR, "rac failure at %d pass %d version %d\n", i, p, version);
88 return 1;
89 }
90
91 if (rac_check_termination(&c, version) < 0) {
92 av_log(NULL, AV_LOG_ERROR, "rac failure at termination pass %d version %d\n", p, version);
93 return 1;
94 }
95 if (c.bytestream - c.bytestream_start - actual_length != version) {
96 av_log(NULL, AV_LOG_ERROR, "rac failure at pass %d version %d\n", p, version);
97 return 1;
98 }
99 }
100 }
101
102 return 0;
103 }
104