/* * Copyright (C) 2018 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include <array> #include <climits> #include <math.h> #include <audio_utils/sample.h> #include <gtest/gtest.h> static_assert(sizeof(sample_minifloat_t) == sizeof(uint16_t), "sizeof(sample_minifloat_t != sizeof(uint16_t"); static constexpr int signum(float f) { return (f > 0) - (f < 0); } TEST(audio_utils_sample, Convert) { std::vector<float> fvec; // verify minifloat <-> float is a bijection, and monotonic as float for (int i = 0; i <= 0xFFFF; i++) { // construct floats in order const int val = i < 0x8000 ? 0xFFFF - i : i ^ 0x8000; // TODO shouldn't depend on representation in order to skip negative zero if (val == 0x8000) { // This is an undefined value and so we won't test its behavior continue; } // TODO reinterpret_cast<sample_minifloat_t>(val) fails const sample_minifloat_t in = (sample_minifloat_t) val; const float f = float_from_sample(in); const sample_minifloat_t out = sample_from_float(f); ASSERT_EQ(in, out); fvec.push_back(f); } // no longer needed since we construct floats in order // #include <algorithm> // std::sort(fvec.begin(), fvec.end()); float prev = -2.0f; for (auto curr : fvec) { // LT instead of LE because no negative zero ASSERT_LT(prev, curr); int signum_prev = signum(prev); int signum_curr = signum(curr); ASSERT_LE(signum_prev, signum_curr); if (signum_prev == signum_curr) { // confirm ratio between adjacent values (3:45 of "Will it float?" video) float ratio = curr / prev; float lower, upper; // normal if (fabsf(curr) >= 0.001f) { upper = 1.005f; lower = 0.995f; // denormal } else { upper = 2.0f; lower = 0.5f; } ASSERT_GE(ratio, lower) << "prev " << prev << " curr " << curr; ASSERT_LE(ratio, upper) << "prev " << prev << " curr " << curr; } prev = curr; } ASSERT_LT(prev, 2.0f); }