/* * Copyright (c) 2012 The WebM project authors. All Rights Reserved. * * Use of this source code is governed by a BSD-style license * that can be found in the LICENSE file in the root of the source * tree. An additional intellectual property rights grant can be found * in the file PATENTS. All contributing project authors may * be found in the AUTHORS file in the root of the source tree. */#ifndef VPX_TEST_ACM_RANDOM_H_#define VPX_TEST_ACM_RANDOM_H_#include <assert.h>#include <limits>#include "third_party/googletest/src/include/gtest/gtest.h"#include "vpx/vpx_integer.h"namespace libvpx_test {class ACMRandom { public: ACMRandom() : random_(DeterministicSeed()) {} explicit ACMRandom(int seed) : random_(seed) {} void Reset(int seed) { random_.Reseed(seed); } uint16_t Rand16(void) { const uint32_t value = random_.Generate(testing::internal::Random::kMaxRange); return (value >> 15) & 0xffff; } int32_t Rand20Signed(void) { // Use 20 bits: values between 524287 and -524288. const uint32_t value = random_.Generate(1048576); return static_cast<int32_t>(value) - 524288; } int16_t Rand16Signed(void) { // Use 16 bits: values between 32767 and -32768. return static_cast<int16_t>(random_.Generate(65536)); } int16_t Rand13Signed(void) { // Use 13 bits: values between 4095 and -4096. const uint32_t value = random_.Generate(8192); return static_cast<int16_t>(value) - 4096; } int16_t Rand9Signed(void) { // Use 9 bits: values between 255 (0x0FF) and -256 (0x100). const uint32_t value = random_.Generate(512); return static_cast<int16_t>(value) - 256; } uint8_t Rand8(void) { const uint32_t value = random_.Generate(testing::internal::Random::kMaxRange); // There's a bit more entropy in the upper bits of this implementation. return (value >> 23) & 0xff; } uint8_t Rand8Extremes(void) { // Returns a random value near 0 or near 255, to better exercise // saturation behavior. const uint8_t r = Rand8(); return static_cast<uint8_t>((r < 128) ? r << 4 : r >> 4); } uint32_t RandRange(const uint32_t range) { // testing::internal::Random::Generate provides values in the range // testing::internal::Random::kMaxRange. assert(range <= testing::internal::Random::kMaxRange); return random_.Generate(range); } int PseudoUniform(int range) { return random_.Generate(range); } int operator()(int n) { return PseudoUniform(n); } static int DeterministicSeed(void) { return 0xbaba; } private: testing::internal::Random random_;};} // namespace libvpx_test#endif // VPX_TEST_ACM_RANDOM_H_
/*
* Copyright (c) 2012 The WebM project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#ifndef VPX_TEST_ACM_RANDOM_H_
#define VPX_TEST_ACM_RANDOM_H_
#include <assert.h>
#include <limits>
#include "third_party/googletest/src/include/gtest/gtest.h"
#include "vpx/vpx_integer.h"
namespace libvpx_test {
class ACMRandom {
public:
ACMRandom() : random_(DeterministicSeed()) {}
explicit ACMRandom(int seed) : random_(seed) {}
void Reset(int seed) { random_.Reseed(seed); }
uint16_t Rand16(void) {
const uint32_t value =
random_.Generate(testing::internal::Random::kMaxRange);
return (value >> 15) & 0xffff;
}
int32_t Rand20Signed(void) {
// Use 20 bits: values between 524287 and -524288.
const uint32_t value = random_.Generate(1048576);
return static_cast<int32_t>(value) - 524288;
}
int16_t Rand16Signed(void) {
// Use 16 bits: values between 32767 and -32768.
return static_cast<int16_t>(random_.Generate(65536));
}
int16_t Rand13Signed(void) {
// Use 13 bits: values between 4095 and -4096.
const uint32_t value = random_.Generate(8192);
return static_cast<int16_t>(value) - 4096;
}
int16_t Rand9Signed(void) {
// Use 9 bits: values between 255 (0x0FF) and -256 (0x100).
const uint32_t value = random_.Generate(512);
return static_cast<int16_t>(value) - 256;
}
uint8_t Rand8(void) {
const uint32_t value =
random_.Generate(testing::internal::Random::kMaxRange);
// There's a bit more entropy in the upper bits of this implementation.
return (value >> 23) & 0xff;
}
uint8_t Rand8Extremes(void) {
// Returns a random value near 0 or near 255, to better exercise
// saturation behavior.
const uint8_t r = Rand8();
return static_cast<uint8_t>((r < 128) ? r << 4 : r >> 4);
}
uint32_t RandRange(const uint32_t range) {
// testing::internal::Random::Generate provides values in the range
// testing::internal::Random::kMaxRange.
assert(range <= testing::internal::Random::kMaxRange);
return random_.Generate(range);
}
int PseudoUniform(int range) { return random_.Generate(range); }
int operator()(int n) { return PseudoUniform(n); }
static int DeterministicSeed(void) { return 0xbaba; }
private:
testing::internal::Random random_;
};
} // namespace libvpx_test
#endif // VPX_TEST_ACM_RANDOM_H_