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
12#include <math.h>
13#include <stddef.h>
14#include <stdio.h>
15#include <stdlib.h>
16#include <string.h>
17#include <sys/types.h>
18
19#include "test/acm_random.h"
20#include "third_party/googletest/src/include/gtest/gtest.h"
21#include "vpx/vpx_integer.h"
22
23extern "C" {
24#include "vp8/encoder/boolhuff.h"
25#include "vp8/decoder/dboolhuff.h"
26}
27
28namespace {
29const int num_tests = 10;
30
31// In a real use the 'decrypt_state' parameter will be a pointer to a struct
32// with whatever internal state the decryptor uses. For testing we'll just
33// xor with a constant key, and decrypt_state will point to the start of
34// the original buffer.
35const uint8_t secret_key[16] = {
36  0x01, 0x12, 0x23, 0x34, 0x45, 0x56, 0x67, 0x78,
37  0x89, 0x9a, 0xab, 0xbc, 0xcd, 0xde, 0xef, 0xf0
38};
39
40void encrypt_buffer(uint8_t *buffer, int size) {
41  for (int i = 0; i < size; ++i) {
42    buffer[i] ^= secret_key[i & 15];
43  }
44}
45
46void test_decrypt_cb(void *decrypt_state, const uint8_t *input,
47                           uint8_t *output, int count) {
48  int offset = input - reinterpret_cast<uint8_t *>(decrypt_state);
49  for (int i = 0; i < count; i++) {
50    output[i] = input[i] ^ secret_key[(offset + i) & 15];
51  }
52}
53
54}  // namespace
55
56using libvpx_test::ACMRandom;
57
58TEST(VP8, TestBitIO) {
59  ACMRandom rnd(ACMRandom::DeterministicSeed());
60  for (int n = 0; n < num_tests; ++n) {
61    for (int method = 0; method <= 7; ++method) {   // we generate various proba
62      const int kBitsToTest = 1000;
63      uint8_t probas[kBitsToTest];
64
65      for (int i = 0; i < kBitsToTest; ++i) {
66        const int parity = i & 1;
67        probas[i] =
68            (method == 0) ? 0 : (method == 1) ? 255 :
69            (method == 2) ? 128 :
70            (method == 3) ? rnd.Rand8() :
71            (method == 4) ? (parity ? 0 : 255) :
72            // alternate between low and high proba:
73            (method == 5) ? (parity ? rnd(128) : 255 - rnd(128)) :
74            (method == 6) ?
75                (parity ? rnd(64) : 255 - rnd(64)) :
76                (parity ? rnd(32) : 255 - rnd(32));
77      }
78      for (int bit_method = 0; bit_method <= 3; ++bit_method) {
79        const int random_seed = 6432;
80        const int kBufferSize = 10000;
81        ACMRandom bit_rnd(random_seed);
82        BOOL_CODER bw;
83        uint8_t bw_buffer[kBufferSize];
84        vp8_start_encode(&bw, bw_buffer, bw_buffer + kBufferSize);
85
86        int bit = (bit_method == 0) ? 0 : (bit_method == 1) ? 1 : 0;
87        for (int i = 0; i < kBitsToTest; ++i) {
88          if (bit_method == 2) {
89            bit = (i & 1);
90          } else if (bit_method == 3) {
91            bit = bit_rnd(2);
92          }
93          vp8_encode_bool(&bw, bit, static_cast<int>(probas[i]));
94        }
95
96        vp8_stop_encode(&bw);
97
98        BOOL_DECODER br;
99#if CONFIG_DECRYPT
100        encrypt_buffer(bw_buffer, buffer_size);
101        vp8dx_start_decode(&br, bw_buffer, buffer_size,
102                           test_decrypt_cb,
103                           reinterpret_cast<void *>(bw_buffer));
104#else
105        vp8dx_start_decode(&br, bw_buffer, kBufferSize, NULL, NULL);
106#endif
107        bit_rnd.Reset(random_seed);
108        for (int i = 0; i < kBitsToTest; ++i) {
109          if (bit_method == 2) {
110            bit = (i & 1);
111          } else if (bit_method == 3) {
112            bit = bit_rnd(2);
113          }
114          GTEST_ASSERT_EQ(vp8dx_decode_bool(&br, probas[i]), bit)
115              << "pos: "<< i << " / " << kBitsToTest
116              << " bit_method: " << bit_method
117              << " method: " << method;
118        }
119      }
120    }
121  }
122}
123