--- /dev/null
+/*
+ * 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.
+ */
+
+#include <math.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "third_party/googletest/src/include/gtest/gtest.h"
+
+extern "C" {
+#include "vp8/encoder/dct.h"
+#include "vp8/common/idct.h"
+}
+
+#include "acm_random.h"
+#include "vpx/vpx_integer.h"
+
+using libvpx_test::ACMRandom;
+
+namespace {
+
+TEST(VP8Fdct8x8Test, SignBiasCheck) {
+ ACMRandom rnd(ACMRandom::DeterministicSeed());
+ int16_t test_input_block[64];
+ int16_t test_output_block[64];
+ const int pitch = 16;
+ int count_sign_block[64][2];
+ const int count_test_block = 100000;
+
+ memset(count_sign_block, 0, sizeof(count_sign_block));
+
+ for (int i = 0; i < count_test_block; ++i) {
+ // Initialize a test block with input range [-255, 255].
+ for (int j = 0; j < 64; ++j)
+ test_input_block[j] = rnd.Rand8() - rnd.Rand8();
+
+ vp8_short_fdct8x8_c(test_input_block, test_output_block, pitch);
+
+ for (int j = 0; j < 64; ++j) {
+ if (test_output_block[j] < 0)
+ ++count_sign_block[j][0];
+ else if (test_output_block[j] > 0)
+ ++count_sign_block[j][1];
+ }
+ }
+
+ for (int j = 0; j < 64; ++j) {
+ const bool bias_acceptable = (abs(count_sign_block[j][0] -
+ count_sign_block[j][1]) < 1000);
+ EXPECT_TRUE(bias_acceptable)
+ << "Error: 8x8 FDCT has a sign bias > 1%"
+ << " for input range [-255, 255] at index " << j;
+ }
+
+ memset(count_sign_block, 0, sizeof(count_sign_block));
+
+ for (int i = 0; i < count_test_block; ++i) {
+ // Initialize a test block with input range [-15, 15].
+ for (int j = 0; j < 64; ++j)
+ test_input_block[j] = (rnd.Rand8() >> 4) - (rnd.Rand8() >> 4);
+
+ vp8_short_fdct8x8_c(test_input_block, test_output_block, pitch);
+
+ for (int j = 0; j < 64; ++j) {
+ if (test_output_block[j] < 0)
+ ++count_sign_block[j][0];
+ else if (test_output_block[j] > 0)
+ ++count_sign_block[j][1];
+ }
+ }
+
+ for (int j = 0; j < 64; ++j) {
+ const bool bias_acceptable = (abs(count_sign_block[j][0] -
+ count_sign_block[j][1]) < 10000);
+ EXPECT_TRUE(bias_acceptable)
+ << "Error: 8x8 FDCT has a sign bias > 10%"
+ << " for input range [-15, 15] at index " << j;
+ }
+};
+
+TEST(VP8Fdct8x8Test, RoundTripErrorCheck) {
+ ACMRandom rnd(ACMRandom::DeterministicSeed());
+ int max_error = 0;
+ double total_error = 0;
+ const int count_test_block = 100000;
+ for (int i = 0; i < count_test_block; ++i) {
+ int16_t test_input_block[64];
+ int16_t test_temp_block[64];
+ int16_t test_output_block[64];
+
+ // Initialize a test block with input range [-255, 255].
+ for (int j = 0; j < 64; ++j)
+ test_input_block[j] = rnd.Rand8() - rnd.Rand8();
+
+ const int pitch = 16;
+ vp8_short_fdct8x8_c(test_input_block, test_temp_block, pitch);
+ vp8_short_idct8x8_c(test_temp_block, test_output_block, pitch);
+
+ for (int j = 0; j < 64; ++j) {
+ const int diff = test_input_block[j] - test_output_block[j];
+ const int error = diff * diff;
+ if (max_error < error)
+ max_error = error;
+ total_error += error;
+ }
+ }
+
+ EXPECT_GE(1, max_error)
+ << "Error: 8x8 FDCT/IDCT has an individual roundtrip error > 1";
+
+ EXPECT_GE(count_test_block, total_error)
+ << "Error: 8x8 FDCT/IDCT has average roundtrip error > 1 per block";
+};
+
+TEST(VP8Fdct8x8Test, ExtremalCheck) {
+ ACMRandom rnd(ACMRandom::DeterministicSeed());
+ int max_error = 0;
+ double total_error = 0;
+ const int count_test_block = 100000;
+ for (int i = 0; i < count_test_block; ++i) {
+ int16_t test_input_block[64];
+ int16_t test_temp_block[64];
+ int16_t test_output_block[64];
+
+ // Initialize a test block with input range {-255, 255}.
+ for (int j = 0; j < 64; ++j)
+ test_input_block[j] = rnd.Rand8() % 2 ? 255 : -255;
+
+ const int pitch = 16;
+ vp8_short_fdct8x8_c(test_input_block, test_temp_block, pitch);
+ vp8_short_idct8x8_c(test_temp_block, test_output_block, pitch);
+
+ for (int j = 0; j < 64; ++j) {
+ const int diff = test_input_block[j] - test_output_block[j];
+ const int error = diff * diff;
+ if (max_error < error)
+ max_error = error;
+ total_error += error;
+ }
+
+ EXPECT_GE(1, max_error)
+ << "Error: Extremal 8x8 FDCT/IDCT has an"
+ << " individual roundtrip error > 1";
+
+ EXPECT_GE(count_test_block, total_error)
+ << "Error: Extremal 8x8 FDCT/IDCT has average"
+ << " roundtrip error > 1 per block";
+ }
+};
+
+} // namespace