1 files changed, 87 insertions, 0 deletions
diff --git a/media/libvpx/libvpx/test/idct8x8_test.cc b/media/libvpx/libvpx/test/idct8x8_test.cc
new file mode 100644
index 0000000000..7951bb93c9
--- /dev/null
+++ b/media/libvpx/libvpx/test/idct8x8_test.cc
@@ -0,0 +1,87 @@
+/*
+ *  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"
+
+#include "./vpx_dsp_rtcd.h"
+#include "test/acm_random.h"
+#include "vpx/vpx_integer.h"
+#include "vpx_ports/msvc.h"  // for round()
+
+using libvpx_test::ACMRandom;
+
+namespace {
+
+void reference_dct_1d(double input[8], double output[8]) {
+  const double kPi = 3.141592653589793238462643383279502884;
+  const double kInvSqrt2 = 0.707106781186547524400844362104;
+  for (int k = 0; k < 8; k++) {
+    output[k] = 0.0;
+    for (int n = 0; n < 8; n++) {
+      output[k] += input[n] * cos(kPi * (2 * n + 1) * k / 16.0);
+    }
+    if (k == 0) output[k] = output[k] * kInvSqrt2;
+  }
+}
+
+void reference_dct_2d(int16_t input[64], double output[64]) {
+  // First transform columns
+  for (int i = 0; i < 8; ++i) {
+    double temp_in[8], temp_out[8];
+    for (int j = 0; j < 8; ++j) temp_in[j] = input[j * 8 + i];
+    reference_dct_1d(temp_in, temp_out);
+    for (int j = 0; j < 8; ++j) output[j * 8 + i] = temp_out[j];
+  }
+  // Then transform rows
+  for (int i = 0; i < 8; ++i) {
+    double temp_in[8], temp_out[8];
+    for (int j = 0; j < 8; ++j) temp_in[j] = output[j + i * 8];
+    reference_dct_1d(temp_in, temp_out);
+    for (int j = 0; j < 8; ++j) output[j + i * 8] = temp_out[j];
+  }
+  // Scale by some magic number
+  for (int i = 0; i < 64; ++i) output[i] *= 2;
+}
+
+TEST(VP9Idct8x8Test, AccuracyCheck) {
+  ACMRandom rnd(ACMRandom::DeterministicSeed());
+  const int count_test_block = 10000;
+  for (int i = 0; i < count_test_block; ++i) {
+    int16_t input[64];
+    tran_low_t coeff[64];
+    double output_r[64];
+    uint8_t dst[64], src[64];
+
+    for (int j = 0; j < 64; ++j) {
+      src[j] = rnd.Rand8();
+      dst[j] = rnd.Rand8();
+    }
+    // Initialize a test block with input range [-255, 255].
+    for (int j = 0; j < 64; ++j) input[j] = src[j] - dst[j];
+
+    reference_dct_2d(input, output_r);
+    for (int j = 0; j < 64; ++j) {
+      coeff[j] = static_cast<tran_low_t>(round(output_r[j]));
+    }
+    vpx_idct8x8_64_add_c(coeff, dst, 8);
+    for (int j = 0; j < 64; ++j) {
+      const int diff = dst[j] - src[j];
+      const int error = diff * diff;
+      EXPECT_GE(1, error) << "Error: 8x8 FDCT/IDCT has error " << error
+                          << " at index " << j;
+    }
+  }
+}
+
+}  // namespace