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Diffstat (limited to '')
-rw-r--r-- | third_party/aom/test/boolcoder_test.cc | 173 |
1 files changed, 173 insertions, 0 deletions
diff --git a/third_party/aom/test/boolcoder_test.cc b/third_party/aom/test/boolcoder_test.cc new file mode 100644 index 0000000000..52c58e0b2e --- /dev/null +++ b/third_party/aom/test/boolcoder_test.cc @@ -0,0 +1,173 @@ +/* + * Copyright (c) 2016, Alliance for Open Media. All rights reserved + * + * This source code is subject to the terms of the BSD 2 Clause License and + * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License + * was not distributed with this source code in the LICENSE file, you can + * obtain it at www.aomedia.org/license/software. If the Alliance for Open + * Media Patent License 1.0 was not distributed with this source code in the + * PATENTS file, you can obtain it at www.aomedia.org/license/patent. + */ + +#include <math.h> +#include <stdlib.h> +#include <string.h> + +#include "third_party/googletest/src/googletest/include/gtest/gtest.h" + +#include "test/acm_random.h" +#include "aom/aom_integer.h" +#include "aom_dsp/bitreader.h" +#include "aom_dsp/bitwriter.h" + +using libaom_test::ACMRandom; + +namespace { +const int num_tests = 10; +} // namespace + +TEST(AV1, TestBitIO) { + ACMRandom rnd(ACMRandom::DeterministicSeed()); + for (int n = 0; n < num_tests; ++n) { + for (int method = 0; method <= 7; ++method) { // we generate various proba + const int kBitsToTest = 1000; + uint8_t probas[kBitsToTest]; + + for (int i = 0; i < kBitsToTest; ++i) { + const int parity = i & 1; + /* clang-format off */ + probas[i] = + (method == 0) ? 0 : (method == 1) ? 255 : + (method == 2) ? 128 : + (method == 3) ? rnd.Rand8() : + (method == 4) ? (parity ? 0 : 255) : + // alternate between low and high proba: + (method == 5) ? (parity ? rnd(128) : 255 - rnd(128)) : + (method == 6) ? + (parity ? rnd(64) : 255 - rnd(64)) : + (parity ? rnd(32) : 255 - rnd(32)); + /* clang-format on */ + } + for (int bit_method = 0; bit_method <= 3; ++bit_method) { + const int random_seed = 6432; + const int kBufferSize = 10000; + ACMRandom bit_rnd(random_seed); + aom_writer bw; + uint8_t bw_buffer[kBufferSize]; + aom_start_encode(&bw, bw_buffer); + + int bit = (bit_method == 0) ? 0 : (bit_method == 1) ? 1 : 0; + for (int i = 0; i < kBitsToTest; ++i) { + if (bit_method == 2) { + bit = (i & 1); + } else if (bit_method == 3) { + bit = bit_rnd(2); + } + aom_write(&bw, bit, static_cast<int>(probas[i])); + } + + GTEST_ASSERT_GE(aom_stop_encode(&bw), 0); + + aom_reader br; + aom_reader_init(&br, bw_buffer, bw.pos); + bit_rnd.Reset(random_seed); + for (int i = 0; i < kBitsToTest; ++i) { + if (bit_method == 2) { + bit = (i & 1); + } else if (bit_method == 3) { + bit = bit_rnd(2); + } + GTEST_ASSERT_EQ(aom_read(&br, probas[i], nullptr), bit) + << "pos: " << i << " / " << kBitsToTest + << " bit_method: " << bit_method << " method: " << method; + } + } + } + } +} + +#define FRAC_DIFF_TOTAL_ERROR 0.18 + +TEST(AV1, TestTell) { + const int kBufferSize = 10000; + aom_writer bw; + uint8_t bw_buffer[kBufferSize]; + const int kSymbols = 1024; + // Coders are noisier at low probabilities, so we start at p = 4. + for (int p = 4; p < 256; p++) { + double probability = p / 256.; + aom_start_encode(&bw, bw_buffer); + for (int i = 0; i < kSymbols; i++) { + aom_write(&bw, 0, p); + } + GTEST_ASSERT_GE(aom_stop_encode(&bw), 0); + aom_reader br; + aom_reader_init(&br, bw_buffer, bw.pos); + uint32_t last_tell = aom_reader_tell(&br); + uint32_t last_tell_frac = aom_reader_tell_frac(&br); + double frac_diff_total = 0; + GTEST_ASSERT_GE(aom_reader_tell(&br), 0u); + GTEST_ASSERT_LE(aom_reader_tell(&br), 1u); + ASSERT_FALSE(aom_reader_has_overflowed(&br)); + for (int i = 0; i < kSymbols; i++) { + aom_read(&br, p, nullptr); + uint32_t tell = aom_reader_tell(&br); + uint32_t tell_frac = aom_reader_tell_frac(&br); + GTEST_ASSERT_GE(tell, last_tell) + << "tell: " << tell << ", last_tell: " << last_tell; + GTEST_ASSERT_GE(tell_frac, last_tell_frac) + << "tell_frac: " << tell_frac + << ", last_tell_frac: " << last_tell_frac; + // Frac tell should round up to tell. + GTEST_ASSERT_EQ(tell, (tell_frac + 7) >> 3); + last_tell = tell; + frac_diff_total += + fabs(((tell_frac - last_tell_frac) / 8.0) + log2(probability)); + last_tell_frac = tell_frac; + } + const uint32_t expected = (uint32_t)(-kSymbols * log2(probability)); + // Last tell should be close to the expected value. + GTEST_ASSERT_LE(last_tell, expected + 20) << " last_tell: " << last_tell; + // The average frac_diff error should be pretty small. + GTEST_ASSERT_LE(frac_diff_total / kSymbols, FRAC_DIFF_TOTAL_ERROR) + << " frac_diff_total: " << frac_diff_total; + ASSERT_FALSE(aom_reader_has_overflowed(&br)); + } +} + +TEST(AV1, TestHasOverflowed) { + const int kBufferSize = 10000; + aom_writer bw; + uint8_t bw_buffer[kBufferSize]; + const int kSymbols = 1024; + // Coders are noisier at low probabilities, so we start at p = 4. + for (int p = 4; p < 256; p++) { + aom_start_encode(&bw, bw_buffer); + for (int i = 0; i < kSymbols; i++) { + aom_write(&bw, 1, p); + } + GTEST_ASSERT_GE(aom_stop_encode(&bw), 0); + aom_reader br; + aom_reader_init(&br, bw_buffer, bw.pos); + ASSERT_FALSE(aom_reader_has_overflowed(&br)); + for (int i = 0; i < kSymbols; i++) { + GTEST_ASSERT_EQ(aom_read(&br, p, nullptr), 1); + ASSERT_FALSE(aom_reader_has_overflowed(&br)); + } + // In the worst case, the encoder uses just a tiny fraction of the last + // byte in the buffer. So to guarantee that aom_reader_has_overflowed() + // returns true, we have to consume very nearly 8 additional bits of data. + // In the worse case, one of the bits in that byte will be 1, and the rest + // will be zero. Once we are past that 1 bit, when the probability of + // reading zero symbol from aom_read() is high, each additional symbol read + // will consume very little additional data (in the case that p == 255, + // approximately -log_2(255/256) ~= 0.0056 bits). In that case it would + // take around 178 calls to consume more than 8 bits. That is only an upper + // bound. In practice we are not guaranteed to hit the worse case and can + // get away with 174 calls. + for (int i = 0; i < 174; i++) { + aom_read(&br, p, nullptr); + } + ASSERT_TRUE(aom_reader_has_overflowed(&br)); + } +} |