1/* 2 * Copyright (c) 2013 The WebRTC project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11// Modified from the Chromium original: 12// src/media/base/sinc_resampler.cc 13 14#include "webrtc/common_audio/resampler/sinc_resampler.h" 15 16#include <arm_neon.h> 17 18namespace webrtc { 19 20float SincResampler::Convolve_NEON(const float* input_ptr, const float* k1, 21 const float* k2, 22 double kernel_interpolation_factor) { 23 float32x4_t m_input; 24 float32x4_t m_sums1 = vmovq_n_f32(0); 25 float32x4_t m_sums2 = vmovq_n_f32(0); 26 27 const float* upper = input_ptr + kKernelSize; 28 for (; input_ptr < upper; ) { 29 m_input = vld1q_f32(input_ptr); 30 input_ptr += 4; 31 m_sums1 = vmlaq_f32(m_sums1, m_input, vld1q_f32(k1)); 32 k1 += 4; 33 m_sums2 = vmlaq_f32(m_sums2, m_input, vld1q_f32(k2)); 34 k2 += 4; 35 } 36 37 // Linearly interpolate the two "convolutions". 38 m_sums1 = vmlaq_f32( 39 vmulq_f32(m_sums1, vmovq_n_f32(1.0 - kernel_interpolation_factor)), 40 m_sums2, vmovq_n_f32(kernel_interpolation_factor)); 41 42 // Sum components together. 43 float32x2_t m_half = vadd_f32(vget_high_f32(m_sums1), vget_low_f32(m_sums1)); 44 return vget_lane_f32(vpadd_f32(m_half, m_half), 0); 45} 46 47} // namespace webrtc 48