1 /*
2 * Copyright (c) 2012 The WebM project authors. All Rights Reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10
11 #include <math.h>
12 #include <stddef.h>
13 #include <stdio.h>
14 #include <stdlib.h>
15 #include <string.h>
16 #include <sys/types.h>
17
18 #include "gtest/gtest.h"
19
20 #include "test/acm_random.h"
21 #include "vp8/decoder/dboolhuff.h"
22 #include "vp8/encoder/boolhuff.h"
23 #include "vpx/vpx_integer.h"
24
25 namespace {
26 const int num_tests = 10;
27
28 // In a real use the 'decrypt_state' parameter will be a pointer to a struct
29 // with whatever internal state the decryptor uses. For testing we'll just
30 // xor with a constant key, and decrypt_state will point to the start of
31 // the original buffer.
32 const uint8_t secret_key[16] = {
33 0x01, 0x12, 0x23, 0x34, 0x45, 0x56, 0x67, 0x78,
34 0x89, 0x9a, 0xab, 0xbc, 0xcd, 0xde, 0xef, 0xf0
35 };
36
encrypt_buffer(uint8_t * buffer,size_t size)37 void encrypt_buffer(uint8_t *buffer, size_t size) {
38 for (size_t i = 0; i < size; ++i) {
39 buffer[i] ^= secret_key[i & 15];
40 }
41 }
42
test_decrypt_cb(void * decrypt_state,const uint8_t * input,uint8_t * output,int count)43 void test_decrypt_cb(void *decrypt_state, const uint8_t *input, uint8_t *output,
44 int count) {
45 const size_t offset = input - reinterpret_cast<uint8_t *>(decrypt_state);
46 for (int i = 0; i < count; i++) {
47 output[i] = input[i] ^ secret_key[(offset + i) & 15];
48 }
49 }
50
51 } // namespace
52
53 using libvpx_test::ACMRandom;
54
TEST(VP8,TestBitIO)55 TEST(VP8, TestBitIO) {
56 ACMRandom rnd(ACMRandom::DeterministicSeed());
57 for (int n = 0; n < num_tests; ++n) {
58 for (int method = 0; method <= 7; ++method) { // we generate various proba
59 const int kBitsToTest = 1000;
60 uint8_t probas[kBitsToTest];
61
62 for (int i = 0; i < kBitsToTest; ++i) {
63 const int parity = i & 1;
64 /* clang-format off */
65 probas[i] =
66 (method == 0) ? 0 : (method == 1) ? 255 :
67 (method == 2) ? 128 :
68 (method == 3) ? rnd.Rand8() :
69 (method == 4) ? (parity ? 0 : 255) :
70 // alternate between low and high proba:
71 (method == 5) ? (parity ? rnd(128) : 255 - rnd(128)) :
72 (method == 6) ?
73 (parity ? rnd(64) : 255 - rnd(64)) :
74 (parity ? rnd(32) : 255 - rnd(32));
75 /* clang-format on */
76 }
77 for (int bit_method = 0; bit_method <= 3; ++bit_method) {
78 const int random_seed = 6432;
79 const int kBufferSize = 10000;
80 ACMRandom bit_rnd(random_seed);
81 BOOL_CODER bw;
82 uint8_t bw_buffer[kBufferSize];
83 vp8_start_encode(&bw, bw_buffer, bw_buffer + kBufferSize);
84
85 int bit = (bit_method == 0) ? 0 : (bit_method == 1) ? 1 : 0;
86 for (int i = 0; i < kBitsToTest; ++i) {
87 if (bit_method == 2) {
88 bit = (i & 1);
89 } else if (bit_method == 3) {
90 bit = bit_rnd(2);
91 }
92 vp8_encode_bool(&bw, bit, static_cast<int>(probas[i]));
93 }
94
95 vp8_stop_encode(&bw);
96 // vp8dx_bool_decoder_fill() may read into uninitialized data that
97 // isn't used meaningfully, but may trigger an MSan warning.
98 memset(bw_buffer + bw.pos, 0, sizeof(VP8_BD_VALUE) - 1);
99
100 BOOL_DECODER br;
101 encrypt_buffer(bw_buffer, kBufferSize);
102 vp8dx_start_decode(&br, bw_buffer, kBufferSize, test_decrypt_cb,
103 reinterpret_cast<void *>(bw_buffer));
104 bit_rnd.Reset(random_seed);
105 for (int i = 0; i < kBitsToTest; ++i) {
106 if (bit_method == 2) {
107 bit = (i & 1);
108 } else if (bit_method == 3) {
109 bit = bit_rnd(2);
110 }
111 GTEST_ASSERT_EQ(vp8dx_decode_bool(&br, probas[i]), bit)
112 << "pos: " << i << " / " << kBitsToTest
113 << " bit_method: " << bit_method << " method: " << method;
114 }
115 }
116 }
117 }
118 }
119