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Add fir_filter to common_audio

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It has 3 implementation:
* fir_filter_c with no optimization
* fir_filter_sse which outperforms the C version by a factor of 3x
* fir_filter_neon which outperforms the C version by a factor of 2x

R=andrew@webrtc.org, bjornv@webrtc.org, johannkoenig@google.com

Review URL: https://webrtc-codereview.appspot.com/9759004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@5756 4adac7df-926f-26a2-2b94-8c16560cd09d
This commit is contained in:
aluebs@webrtc.org 2014-03-24 10:16:11 +00:00
parent af839b28b0
commit 37ca765650
8 changed files with 599 additions and 0 deletions
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7
webrtc/common_audio/common_audio.gyp
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@ -30,6 +30,10 @@
},
'sources': [
'audio_util.cc',
'fir_filter.cc',
'fir_filter.h',
'fir_filter_neon.h',
'fir_filter_sse.h',
'include/audio_util.h',
'resampler/include/push_resampler.h',
'resampler/include/resampler.h',
@ -152,6 +156,7 @@
'target_name': 'common_audio_sse2',
'type': 'static_library',
'sources': [
'fir_filter_sse.cc',
'resampler/sinc_resampler_sse.cc',
],
'cflags': ['-msse2',],
@ -168,6 +173,7 @@
'type': 'static_library',
'includes': ['../build/arm_neon.gypi',],
'sources': [
'fir_filter_neon.cc',
'resampler/sinc_resampler_neon.cc',
'signal_processing/cross_correlation_neon.S',
'signal_processing/downsample_fast_neon.S',
@ -190,6 +196,7 @@
],
'sources': [
'audio_util_unittest.cc',
'fir_filter_unittest.cc',
'resampler/resampler_unittest.cc',
'resampler/push_resampler_unittest.cc',
'resampler/push_sinc_resampler_unittest.cc',

119
webrtc/common_audio/fir_filter.cc Normal file
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/*
* Copyright (c) 2014 The WebRTC 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 "webrtc/common_audio/fir_filter.h"
#include <assert.h>
#include <string.h>
#include "webrtc/common_audio/fir_filter_neon.h"
#include "webrtc/common_audio/fir_filter_sse.h"
#include "webrtc/system_wrappers/interface/cpu_features_wrapper.h"
#include "webrtc/system_wrappers/interface/scoped_ptr.h"
namespace webrtc {
class FIRFilterC : public FIRFilter {
public:
FIRFilterC(const float* coefficients,
size_t coefficients_length);
virtual void Filter(const float* in, size_t length, float* out) OVERRIDE;
private:
size_t coefficients_length_;
size_t state_length_;
scoped_ptr<float[]> coefficients_;
scoped_ptr<float[]> state_;
};
FIRFilter* FIRFilter::Create(const float* coefficients,
size_t coefficients_length,
size_t max_input_length) {
if (!coefficients || coefficients_length <= 0 || max_input_length <= 0) {
assert(false);
return NULL;
}
FIRFilter* filter = NULL;
// If we know the minimum architecture at compile time, avoid CPU detection.
#if defined(WEBRTC_ARCH_X86_FAMILY)
#if defined(__SSE2__)
filter =
new FIRFilterSSE2(coefficients, coefficients_length, max_input_length);
#else
// x86 CPU detection required.
if (WebRtc_GetCPUInfo(kSSE2)) {
filter =
new FIRFilterSSE2(coefficients, coefficients_length, max_input_length);
} else {
filter = new FIRFilterC(coefficients, coefficients_length);
}
#endif
#elif defined(WEBRTC_ARCH_ARM_V7)
#if defined(WEBRTC_ARCH_ARM_NEON)
filter =
new FIRFilterNEON(coefficients, coefficients_length, max_input_length);
#else
// ARM CPU detection required.
if (WebRtc_GetCPUFeaturesARM() & kCPUFeatureNEON) {
filter =
new FIRFilterNEON(coefficients, coefficients_length, max_input_length);
} else {
filter = new FIRFilterC(coefficients, coefficients_length);
}
#endif
#else
filter = new FIRFilterC(coefficients, coefficients_length);
#endif
return filter;
}
FIRFilterC::FIRFilterC(const float* coefficients, size_t coefficients_length)
: coefficients_length_(coefficients_length),
state_length_(coefficients_length - 1),
coefficients_(new float[coefficients_length_]),
state_(new float[state_length_]) {
for (size_t i = 0; i < coefficients_length_; ++i) {
coefficients_[i] = coefficients[coefficients_length_ - i - 1];
}
memset(state_.get(), 0.f, state_length_ * sizeof(state_[0]));
}
void FIRFilterC::Filter(const float* in, size_t length, float* out) {
assert(length > 0);
// Convolves the input signal |in| with the filter kernel |coefficients_|
// taking into account the previous state.
for (size_t i = 0; i < length; ++i) {
out[i] = 0.f;
size_t j;
for (j = 0; state_length_ > i && j < state_length_ - i; ++j) {
out[i] += state_[i + j] * coefficients_[j];
}
for (; j < coefficients_length_; ++j) {
out[i] += in[j + i - state_length_] * coefficients_[j];
}
}
// Update current state.
if (length >= state_length_) {
memcpy(
state_.get(), &in[length - state_length_], state_length_ * sizeof(*in));
} else {
memmove(state_.get(),
&state_[length],
(state_length_ - length) * sizeof(state_[0]));
memcpy(&state_[state_length_ - length], in, length * sizeof(*in));
}
}
} // namespace webrtc

40
webrtc/common_audio/fir_filter.h Normal file
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/*
* Copyright (c) 2014 The WebRTC 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 WEBRTC_COMMON_AUDIO_FIR_FILTER_H_
#define WEBRTC_COMMON_AUDIO_FIR_FILTER_H_
#include <string.h>
namespace webrtc {
// Finite Impulse Response filter using floating-point arithmetic.
class FIRFilter {
public:
// Creates a filter with the given coefficients. All initial state values will
// be zeros.
// The length of the chunks fed to the filter should never be greater than
// |max_input_length|. This is needed because, when vectorizing it is
// necessary to concatenate the input after the state, and resizing this array
// dynamically is expensive.
static FIRFilter* Create(const float* coefficients,
size_t coefficients_length,
size_t max_input_length);
virtual ~FIRFilter() {}
// Filters the |in| data supplied.
// |out| must be previously allocated and it must be at least of |length|.
virtual void Filter(const float* in, size_t length, float* out) = 0;
};
} // namespace webrtc
#endif // WEBRTC_COMMON_AUDIO_FIR_FILTER_H_

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webrtc/common_audio/fir_filter_neon.cc Normal file
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/*
* Copyright (c) 2014 The WebRTC 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 "webrtc/common_audio/fir_filter_neon.h"
#include <arm_neon.h>
#include <assert.h>
#include <string.h>
#include "webrtc/system_wrappers/interface/aligned_malloc.h"
namespace webrtc {
FIRFilterNEON::FIRFilterNEON(const float* coefficients,
size_t coefficients_length,
size_t max_input_length)
: // Closest higher multiple of four.
coefficients_length_((coefficients_length + 3) & ~0x03),
state_length_(coefficients_length_ - 1),
coefficients_(static_cast<float*>(
AlignedMalloc(sizeof(float) * coefficients_length_, 16))),
state_(static_cast<float*>(
AlignedMalloc(sizeof(float) * (max_input_length + state_length_),
16))) {
// Add zeros at the end of the coefficients.
size_t padding = coefficients_length_ - coefficients_length;
memset(coefficients_.get(), 0.f, padding * sizeof(coefficients_[0]));
// The coefficients are reversed to compensate for the order in which the
// input samples are acquired (most recent last).
for (size_t i = 0; i < coefficients_length; ++i) {
coefficients_[i + padding] = coefficients[coefficients_length - i - 1];
}
memset(state_.get(),
0.f,
(max_input_length + state_length_) * sizeof(state_[0]));
}
void FIRFilterNEON::Filter(const float* in, size_t length, float* out) {
assert(length > 0);
memcpy(&state_[state_length_], in, length * sizeof(*in));
// Convolves the input signal |in| with the filter kernel |coefficients_|
// taking into account the previous state.
for (size_t i = 0; i < length; ++i) {
float* in_ptr = &state_[i];
float* coef_ptr = coefficients_.get();
float32x4_t m_sum = vmovq_n_f32(0);
float32x4_t m_in;
for (size_t j = 0; j < coefficients_length_; j += 4) {
m_in = vld1q_f32(in_ptr + j);
m_sum = vmlaq_f32(m_sum, m_in, vld1q_f32(coef_ptr + j));
}
float32x2_t m_half = vadd_f32(vget_high_f32(m_sum), vget_low_f32(m_sum));
out[i] = vget_lane_f32(vpadd_f32(m_half, m_half), 0);
}
// Update current state.
memmove(state_.get(), &state_[length], state_length_ * sizeof(state_[0]));
}
} // namespace webrtc

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webrtc/common_audio/fir_filter_neon.h Normal file
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/*
* Copyright (c) 2014 The WebRTC 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 WEBRTC_COMMON_AUDIO_FIR_FILTER_NEON_H_
#define WEBRTC_COMMON_AUDIO_FIR_FILTER_NEON_H_
#include "webrtc/common_audio/fir_filter.h"
#include "webrtc/system_wrappers/interface/aligned_malloc.h"
#include "webrtc/system_wrappers/interface/scoped_ptr.h"
namespace webrtc {
class FIRFilterNEON : public FIRFilter {
public:
FIRFilterNEON(const float* coefficients,
size_t coefficients_length,
size_t max_input_length);
virtual void Filter(const float* in, size_t length, float* out) OVERRIDE;
private:
size_t coefficients_length_;
size_t state_length_;
scoped_ptr<float[], AlignedFreeDeleter> coefficients_;
scoped_ptr<float[], AlignedFreeDeleter> state_;
};
} // namespace webrtc
#endif // WEBRTC_COMMON_AUDIO_FIR_FILTER_NEON_H_

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webrtc/common_audio/fir_filter_sse.cc Normal file
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/*
* Copyright (c) 2014 The WebRTC 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 "webrtc/common_audio/fir_filter_sse.h"
#include <assert.h>
#include <string.h>
#include <xmmintrin.h>
#include "webrtc/system_wrappers/interface/aligned_malloc.h"
namespace webrtc {
FIRFilterSSE2::FIRFilterSSE2(const float* coefficients,
size_t coefficients_length,
size_t max_input_length)
: // Closest higher multiple of four.
coefficients_length_((coefficients_length + 3) & ~0x03),
state_length_(coefficients_length_ - 1),
coefficients_(static_cast<float*>(
AlignedMalloc(sizeof(float) * coefficients_length_, 16))),
state_(static_cast<float*>(
AlignedMalloc(sizeof(float) * (max_input_length + state_length_),
16))) {
// Add zeros at the end of the coefficients.
size_t padding = coefficients_length_ - coefficients_length;
memset(coefficients_.get(), 0.f, padding * sizeof(coefficients_[0]));
// The coefficients are reversed to compensate for the order in which the
// input samples are acquired (most recent last).
for (size_t i = 0; i < coefficients_length; ++i) {
coefficients_[i + padding] = coefficients[coefficients_length - i - 1];
}
memset(state_.get(),
0.f,
(max_input_length + state_length_) * sizeof(state_[0]));
}
void FIRFilterSSE2::Filter(const float* in, size_t length, float* out) {
assert(length > 0);
memcpy(&state_[state_length_], in, length * sizeof(*in));
// Convolves the input signal |in| with the filter kernel |coefficients_|
// taking into account the previous state.
for (size_t i = 0; i < length; ++i) {
float* in_ptr = &state_[i];
float* coef_ptr = coefficients_.get();
__m128 m_sum = _mm_setzero_ps();
__m128 m_in;
// Depending on if the pointer is aligned with 16 bytes or not it is loaded
// differently.
if (reinterpret_cast<uintptr_t>(in_ptr) & 0x0F) {
for (size_t j = 0; j < coefficients_length_; j += 4) {
m_in = _mm_loadu_ps(in_ptr + j);
m_sum = _mm_add_ps(m_sum, _mm_mul_ps(m_in, _mm_load_ps(coef_ptr + j)));
}
} else {
for (size_t j = 0; j < coefficients_length_; j += 4) {
m_in = _mm_load_ps(in_ptr + j);
m_sum = _mm_add_ps(m_sum, _mm_mul_ps(m_in, _mm_load_ps(coef_ptr + j)));
}
}
m_sum = _mm_add_ps(_mm_movehl_ps(m_sum, m_sum), m_sum);
_mm_store_ss(out + i, _mm_add_ss(m_sum, _mm_shuffle_ps(m_sum, m_sum, 1)));
}
// Update current state.
memmove(state_.get(), &state_[length], state_length_ * sizeof(state_[0]));
}
} // namespace webrtc

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webrtc/common_audio/fir_filter_sse.h Normal file
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/*
* Copyright (c) 2014 The WebRTC 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 WEBRTC_COMMON_AUDIO_FIR_FILTER_SSE_H_
#define WEBRTC_COMMON_AUDIO_FIR_FILTER_SSE_H_
#include "webrtc/common_audio/fir_filter.h"
#include "webrtc/system_wrappers/interface/aligned_malloc.h"
#include "webrtc/system_wrappers/interface/scoped_ptr.h"
namespace webrtc {
class FIRFilterSSE2 : public FIRFilter {
public:
FIRFilterSSE2(const float* coefficients,
size_t coefficients_length,
size_t max_input_length);
virtual void Filter(const float* in, size_t length, float* out) OVERRIDE;
private:
size_t coefficients_length_;
size_t state_length_;
scoped_ptr<float[], AlignedFreeDeleter> coefficients_;
scoped_ptr<float[], AlignedFreeDeleter> state_;
};
} // namespace webrtc
#endif // WEBRTC_COMMON_AUDIO_FIR_FILTER_SSE_H_

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webrtc/common_audio/fir_filter_unittest.cc Normal file
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/*
* Copyright (c) 2014 The WebRTC 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 "webrtc/common_audio/fir_filter.h"
#include <string.h>
#include "testing/gtest/include/gtest/gtest.h"
#include "webrtc/system_wrappers/interface/scoped_ptr.h"
namespace webrtc {
static const float kCoefficients[] = {0.2f, 0.3f, 0.5f, 0.7f, 0.11f};
static const size_t kCoefficientsLength = sizeof(kCoefficients) /
sizeof(kCoefficients[0]);
static const float kInput[] = {1.f, 2.f, 3.f, 4.f, 5.f, 6.f, 7.f,
8.f, 9.f, 10.f};
static const size_t kInputLength = sizeof(kInput) /
sizeof(kInput[0]);
void VerifyOutput(const float* expected_output,
const float* output,
size_t length) {
EXPECT_EQ(0, memcmp(expected_output,
output,
length * sizeof(expected_output[0])));
}
TEST(FIRFilterTest, FilterAsIdentity) {
const float kCoefficients[] = {1.f, 0.f, 0.f, 0.f, 0.f};
float output[kInputLength];
scoped_ptr<FIRFilter> filter(FIRFilter::Create(
kCoefficients, kCoefficientsLength, kInputLength));
filter->Filter(kInput, kInputLength, output);
VerifyOutput(kInput, output, kInputLength);
}
TEST(FIRFilterTest, FilterUsedAsScalarMultiplication) {
const float kCoefficients[] = {5.f, 0.f, 0.f, 0.f, 0.f};
float output[kInputLength];
scoped_ptr<FIRFilter> filter(FIRFilter::Create(
kCoefficients, kCoefficientsLength, kInputLength));
filter->Filter(kInput, kInputLength, output);
EXPECT_FLOAT_EQ(5.f, output[0]);
EXPECT_FLOAT_EQ(20.f, output[3]);
EXPECT_FLOAT_EQ(25.f, output[4]);
EXPECT_FLOAT_EQ(50.f, output[kInputLength - 1]);
}
TEST(FIRFilterTest, FilterUsedAsInputShifting) {
const float kCoefficients[] = {0.f, 0.f, 0.f, 0.f, 1.f};
float output[kInputLength];
scoped_ptr<FIRFilter> filter(FIRFilter::Create(
kCoefficients, kCoefficientsLength, kInputLength));
filter->Filter(kInput, kInputLength, output);
EXPECT_FLOAT_EQ(0.f, output[0]);
EXPECT_FLOAT_EQ(0.f, output[3]);
EXPECT_FLOAT_EQ(1.f, output[4]);
EXPECT_FLOAT_EQ(2.f, output[5]);
EXPECT_FLOAT_EQ(6.f, output[kInputLength - 1]);
}
TEST(FIRFilterTest, FilterUsedAsArbitraryWeighting) {
float output[kInputLength];
scoped_ptr<FIRFilter> filter(FIRFilter::Create(
kCoefficients, kCoefficientsLength, kInputLength));
filter->Filter(kInput, kInputLength, output);
EXPECT_FLOAT_EQ(0.2f, output[0]);
EXPECT_FLOAT_EQ(3.4f, output[3]);
EXPECT_FLOAT_EQ(5.21f, output[4]);
EXPECT_FLOAT_EQ(7.02f, output[5]);
EXPECT_FLOAT_EQ(14.26f, output[kInputLength - 1]);
}
TEST(FIRFilterTest, FilterInLengthLesserOrEqualToCoefficientsLength) {
float output[kInputLength];
scoped_ptr<FIRFilter> filter(
FIRFilter::Create(kCoefficients, kCoefficientsLength, 2));
filter->Filter(kInput, 2, output);
EXPECT_FLOAT_EQ(0.2f, output[0]);
EXPECT_FLOAT_EQ(0.7f, output[1]);
filter.reset(FIRFilter::Create(
kCoefficients, kCoefficientsLength, kCoefficientsLength));
filter->Filter(kInput, kCoefficientsLength, output);
EXPECT_FLOAT_EQ(0.2f, output[0]);
EXPECT_FLOAT_EQ(3.4f, output[3]);
EXPECT_FLOAT_EQ(5.21f, output[4]);
}
TEST(FIRFilterTest, MultipleFilterCalls) {
float output[kInputLength];
scoped_ptr<FIRFilter> filter(
FIRFilter::Create(kCoefficients, kCoefficientsLength, 3));
filter->Filter(kInput, 2, output);
EXPECT_FLOAT_EQ(0.2f, output[0]);
EXPECT_FLOAT_EQ(0.7f, output[1]);
filter->Filter(kInput, 2, output);
EXPECT_FLOAT_EQ(1.3f, output[0]);
EXPECT_FLOAT_EQ(2.4f, output[1]);
filter->Filter(kInput, 2, output);
EXPECT_FLOAT_EQ(2.81f, output[0]);
EXPECT_FLOAT_EQ(2.62f, output[1]);
filter->Filter(kInput, 2, output);
EXPECT_FLOAT_EQ(2.81f, output[0]);
EXPECT_FLOAT_EQ(2.62f, output[1]);
filter->Filter(&kInput[3], 3, output);
EXPECT_FLOAT_EQ(3.41f, output[0]);
EXPECT_FLOAT_EQ(4.12f, output[1]);
EXPECT_FLOAT_EQ(6.21f, output[2]);
filter->Filter(&kInput[3], 3, output);
EXPECT_FLOAT_EQ(8.12f, output[0]);
EXPECT_FLOAT_EQ(9.14f, output[1]);
EXPECT_FLOAT_EQ(9.45f, output[2]);
}
TEST(FIRFilterTest, VerifySampleBasedVsBlockBasedFiltering) {
float output_block_based[kInputLength];
scoped_ptr<FIRFilter> filter(FIRFilter::Create(
kCoefficients, kCoefficientsLength, kInputLength));
filter->Filter(kInput, kInputLength, output_block_based);
float output_sample_based[kInputLength];
filter.reset(FIRFilter::Create(kCoefficients, kCoefficientsLength, 1));
for (size_t i = 0; i < kInputLength; ++i) {
filter->Filter(&kInput[i], 1, &output_sample_based[i]);
}
EXPECT_EQ(0, memcmp(output_sample_based,
output_block_based,
kInputLength));
}
TEST(FIRFilterTest, SimplestHighPassFilter) {
const float kCoefficients[] = {1.f, -1.f};
const size_t kCoefficientsLength = sizeof(kCoefficients) /
sizeof(kCoefficients[0]);
float kConstantInput[] = {1.f, 1.f, 1.f, 1.f, 1.f, 1.f, 1.f, 1.f};
const size_t kConstantInputLength = sizeof(kConstantInput) /
sizeof(kConstantInput[0]);
float output[kConstantInputLength];
scoped_ptr<FIRFilter> filter(FIRFilter::Create(
kCoefficients, kCoefficientsLength, kConstantInputLength));
filter->Filter(kConstantInput, kConstantInputLength, output);
EXPECT_FLOAT_EQ(1.f, output[0]);
for (size_t i = kCoefficientsLength - 1; i < kConstantInputLength; ++i) {
EXPECT_FLOAT_EQ(0.f, output[i]);
}
}
TEST(FIRFilterTest, SimplestLowPassFilter) {
const float kCoefficients[] = {1.f, 1.f};
const size_t kCoefficientsLength = sizeof(kCoefficients) /
sizeof(kCoefficients[0]);
float kHighFrequencyInput[] = {-1.f, 1.f, -1.f, 1.f, -1.f, 1.f, -1.f, 1.f};
const size_t kHighFrequencyInputLength = sizeof(kHighFrequencyInput) /
sizeof(kHighFrequencyInput[0]);
float output[kHighFrequencyInputLength];
scoped_ptr<FIRFilter> filter(FIRFilter::Create(
kCoefficients, kCoefficientsLength, kHighFrequencyInputLength));
filter->Filter(kHighFrequencyInput, kHighFrequencyInputLength, output);
EXPECT_FLOAT_EQ(-1.f, output[0]);
for (size_t i = kCoefficientsLength - 1; i < kHighFrequencyInputLength; ++i) {
EXPECT_FLOAT_EQ(0.f, output[i]);
}
}
TEST(FIRFilterTest, SameOutputWhenSwapedCoefficientsAndInput) {
float output[kCoefficientsLength];
float output_swaped[kCoefficientsLength];
scoped_ptr<FIRFilter> filter(FIRFilter::Create(
kCoefficients, kCoefficientsLength, kCoefficientsLength));
// Use kCoefficientsLength for in_length to get same-length outputs.
filter->Filter(kInput, kCoefficientsLength, output);
filter.reset(FIRFilter::Create(
kInput, kCoefficientsLength, kCoefficientsLength));
filter->Filter(kCoefficients, kCoefficientsLength, output_swaped);
for (size_t i = 0 ; i < kCoefficientsLength; ++i) {
EXPECT_FLOAT_EQ(output[i], output_swaped[i]);
}
}
} // namespace webrtc