test/vp8_boolcoder_test.cc

   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
  23 #include "vp8/encoder/boolhuff.h"
  24 #include "vp8/decoder/dboolhuff.h"
  25
  26 namespace {
  27 const int num_tests = 10;
  28
  29 // In a real use the 'decrypt_state' parameter will be a pointer to a struct
  30 // with whatever internal state the decryptor uses. For testing we'll just
  31 // xor with a constant key, and decrypt_state will point to the start of
  32 // the original buffer.
  33 const uint8_t secret_key[16] = {
  34   0x01, 0x12, 0x23, 0x34, 0x45, 0x56, 0x67, 0x78,
  35   0x89, 0x9a, 0xab, 0xbc, 0xcd, 0xde, 0xef, 0xf0
  36 };
  37
  38 void encrypt_buffer(uint8_t *buffer, size_t size) {
  39   for (size_t i = 0; i < size; ++i) {
  40     buffer[i] ^= secret_key[i & 15];
  41   }
  42 }
  43
  44 void test_decrypt_cb(void *decrypt_state, const uint8_t *input,
  45                      uint8_t *output, int count) {
  46   const size_t offset = input - reinterpret_cast<uint8_t*>(decrypt_state);
  47   for (int i = 0; i < count; i++) {
  48     output[i] = input[i] ^ secret_key[(offset + i) & 15];
  49   }
  50 }
  51
  52 }  // namespace
  53
  54 using libvpx_test::ACMRandom;
  55
  56 TEST(VP8, TestBitIO) {
  57   ACMRandom rnd(ACMRandom::DeterministicSeed());
  58   for (int n = 0; n < num_tests; ++n) {
  59     for (int method = 0; method <= 7; ++method) {   // we generate various proba
  60       const int kBitsToTest = 1000;
  61       uint8_t probas[kBitsToTest];
  62
  63       for (int i = 0; i < kBitsToTest; ++i) {
  64         const int parity = i & 1;
  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       }
  76       for (int bit_method = 0; bit_method <= 3; ++bit_method) {
  77         const int random_seed = 6432;
  78         const int kBufferSize = 10000;
  79         ACMRandom bit_rnd(random_seed);
  80         BOOL_CODER bw;
  81         uint8_t bw_buffer[kBufferSize];
  82         vp8_start_encode(&bw, bw_buffer, bw_buffer + kBufferSize);
  83
  84         int bit = (bit_method == 0) ? 0 : (bit_method == 1) ? 1 : 0;
  85         for (int i = 0; i < kBitsToTest; ++i) {
  86           if (bit_method == 2) {
  87             bit = (i & 1);
  88           } else if (bit_method == 3) {
  89             bit = bit_rnd(2);
  90           }
  91           vp8_encode_bool(&bw, bit, static_cast<int>(probas[i]));
  92         }
  93
  94         vp8_stop_encode(&bw);
  95
  96         BOOL_DECODER br;
  97         encrypt_buffer(bw_buffer, kBufferSize);
  98         vp8dx_start_decode(&br, bw_buffer, kBufferSize,
  99                            test_decrypt_cb,
 100                            reinterpret_cast<void *>(bw_buffer));
 101         bit_rnd.Reset(random_seed);
 102         for (int i = 0; i < kBitsToTest; ++i) {
 103           if (bit_method == 2) {
 104             bit = (i & 1);
 105           } else if (bit_method == 3) {
 106             bit = bit_rnd(2);
 107           }
 108           GTEST_ASSERT_EQ(vp8dx_decode_bool(&br, probas[i]), bit)
 109               << "pos: "<< i << " / " << kBitsToTest
 110               << " bit_method: " << bit_method
 111               << " method: " << method;
 112         }
 113       }
 114     }
 115   }
 116 }