Add 8x8 fDCT unit test.

Also factorize ACMRandom to acm_random.h.

Change-Id: I3b6eeb36fcbf7ae6dd3d2892bc40348f5c17982b

test/acm_random.h

+/*
+ *  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.
+ */
+
+#ifndef LIBVPX_TEST_ACM_RANDOM_H_
+#define LIBVPX_TEST_ACM_RANDOM_H_
+
+#include <stdlib.h>
+
+#include "vpx/vpx_integer.h"
+
+namespace libvpx_test {
+
+class ACMRandom {
+ public:
+  explicit ACMRandom(int seed) { Reset(seed); }
+
+  void Reset(int seed) { srand(seed); }
+
+  uint8_t Rand8(void) { return (rand() >> 8) & 0xff; }
+
+  int PseudoUniform(int range) { return (rand() >> 8) % range; }
+
+  int operator()(int n) { return PseudoUniform(n); }
+
+  static int DeterministicSeed(void) { return 0xbaba; }
+};
+
+}  // namespace libvpx_test
+
+#endif  // LIBVPX_TEST_ACM_RANDOM_H_

test/boolcoder_test.cc

@@ -8,38 +8,24 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-extern "C" {
-#include "vp8/encoder/boolhuff.h"
-#include "vp8/decoder/dboolhuff.h"
-}
-
 #include <math.h>
-#include <stddef.h>
-#include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <sys/types.h>
 
 #include "third_party/googletest/src/include/gtest/gtest.h"
-#include "vpx/vpx_integer.h"
-
-namespace {
-const int num_tests = 10;
 
-class ACMRandom {
- public:
-  explicit ACMRandom(int seed) { Reset(seed); }
-
-  void Reset(int seed) { srand(seed); }
-
-  uint8_t Rand8(void) { return (rand() >> 8) & 0xff; }
+extern "C" {
+#include "vp8/encoder/boolhuff.h"
+#include "vp8/decoder/dboolhuff.h"
+}
 
-  int PseudoUniform(int range) { return (rand() >> 8) % range; }
+#include "acm_random.h"
+#include "vpx/vpx_integer.h"
 
-  int operator()(int n) { return PseudoUniform(n); }
+using libvpx_test::ACMRandom;
 
-  static int DeterministicSeed(void) { return 0xbaba; }
-};
+namespace {
+const int num_tests = 10;
 }  // namespace
 
 TEST(VP8, TestBitIO) {

test/fdct4x4_test.cc

@@ -19,24 +19,12 @@ extern "C" {
 #include "vp8/encoder/dct.h"
 }
 
+#include "acm_random.h"
 #include "vpx/vpx_integer.h"
 
-namespace {
-
-class ACMRandom {
- public:
-  explicit ACMRandom(int seed) { Reset(seed); }
-
-  void Reset(int seed) { srand(seed); }
-
-  uint8_t Rand8(void) { return (rand() >> 8) & 0xff; }
+using libvpx_test::ACMRandom;
 
-  int PseudoUniform(int range) { return (rand() >> 8) % range; }
-
-  int operator()(int n) { return PseudoUniform(n); }
-
-  static int DeterministicSeed(void) { return 0xbaba; }
-};
+namespace {
 
 TEST(Vp8FdctTest, SignBiasCheck) {
   ACMRandom rnd(ACMRandom::DeterministicSeed());

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 "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

test/test.mk

 LIBVPX_TEST_SRCS-yes += test.mk
+LIBVPX_TEST_SRCS-yes += acm_random.h
 LIBVPX_TEST_SRCS-yes += boolcoder_test.cc
 LIBVPX_TEST_SRCS-yes += fdct4x4_test.cc
+LIBVPX_TEST_SRCS-yes += fdct8x8_test.cc
 LIBVPX_TEST_SRCS-yes += test_libvpx.cc
 
 LIBVPX_TEST_DATA-yes += hantro_collage_w352h288.yuv