libvpx: Add VP9 decoder.

source/libvpx/test/fdct8x8_test.cc

+/*
+ *  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 "vp9_rtcd.h"
+}
+
+#include "acm_random.h"
+#include "vpx/vpx_integer.h"
+
+using libvpx_test::ACMRandom;
+
+namespace {
+
+TEST(VP9Fdct8x8Test, 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();
+
+    vp9_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);
+
+    vp9_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(VP9Fdct8x8Test, 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;
+    vp9_short_fdct8x8_c(test_input_block, test_temp_block, pitch);
+    for (int j = 0; j < 64; ++j){
+        if(test_temp_block[j] > 0) {
+          test_temp_block[j] += 2;
+          test_temp_block[j] /= 4;
+          test_temp_block[j] *= 4;
+        } else {
+          test_temp_block[j] -= 2;
+          test_temp_block[j] /= 4;
+          test_temp_block[j] *= 4;
+        }
+    }
+    vp9_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/5, total_error)
+      << "Error: 8x8 FDCT/IDCT has average roundtrip error > 1/5 per block";
+};
+
+TEST(VP9Fdct8x8Test, 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;
+    vp9_short_fdct8x8_c(test_input_block, test_temp_block, pitch);
+    vp9_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/5, total_error)
+        << "Error: Extremal 8x8 FDCT/IDCT has average"
+        << " roundtrip error > 1/5 per block";
+  }
+};
+
+}  // namespace