* be found in the AUTHORS file in the root of the source tree.
*/
-#ifndef LIBVPX_TEST_ACM_RANDOM_H_
-#define LIBVPX_TEST_ACM_RANDOM_H_
+#ifndef TEST_ACM_RANDOM_H_
+#define TEST_ACM_RANDOM_H_
-#include <stdlib.h>
+#include "third_party/googletest/src/include/gtest/gtest.h"
#include "vpx/vpx_integer.h"
class ACMRandom {
public:
- explicit ACMRandom(int seed) { Reset(seed); }
+ ACMRandom() : random_(DeterministicSeed()) {}
- void Reset(int seed) { srand(seed); }
+ explicit ACMRandom(int seed) : random_(seed) {}
- uint8_t Rand8(void) { return (rand() >> 8) & 0xff; }
+ 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;
+ }
- int PseudoUniform(int range) { return (rand() >> 8) % range; }
+ 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;
+ }
- int operator()(int n) { return PseudoUniform(n); }
+ uint8_t Rand8Extremes(void) {
+ // Returns a random value near 0 or near 255, to better exercise
+ // saturation behavior.
+ const uint8_t r = Rand8();
+ return r < 128 ? r << 4 : r >> 4;
+ }
- static int DeterministicSeed(void) { return 0xbaba; }
+ 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 // LIBVPX_TEST_ACM_RANDOM_H_
+#endif // TEST_ACM_RANDOM_H_