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