ref: e9b8810b4d5c1db78ef07b6061b05d2d62d55eb6
dir: /test/idct8x8_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" #include "./vp9_rtcd.h" #include "test/acm_random.h" #include "vpx/vpx_integer.h" using libvpx_test::ACMRandom; namespace { #ifdef _MSC_VER static int round(double x) { if (x < 0) return static_cast<int>(ceil(x - 0.5)); else return static_cast<int>(floor(x + 0.5)); } #endif 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; } void reference_idct_1d(double input[8], double output[8]) { const double kPi = 3.141592653589793238462643383279502884; const double kSqrt2 = 1.414213562373095048801688724209698; 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*k+1)*n/16.0); if (n == 0) output[k] = output[k]/kSqrt2; } } } void reference_idct_2d(double input[64], int16_t output[64]) { double out[64], out2[64]; // First 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] = input[j + i*8]; reference_idct_1d(temp_in, temp_out); for (int j = 0; j < 8; ++j) out[j + i*8] = temp_out[j]; } // Then 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] = out[j*8 + i]; reference_idct_1d(temp_in, temp_out); for (int j = 0; j < 8; ++j) out2[j*8 + i] = temp_out[j]; } for (int i = 0; i < 64; ++i) output[i] = round(out2[i]/32); } 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] = round(output_r[j]); vp9_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