Update audio code to use size_t more correctly, webrtc/common_audio/resampler/

webrtc/common_audio/resampler/sinc_resampler.cc

 /*
  *  Copyright (c) 2013 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.
  */
 
@@ skipping 131 matching lines @@
   convolve_proc_ = WebRtc_GetCPUFeaturesARM() & kCPUFeatureNEON ?
       Convolve_NEON : Convolve_C;
 }
 #else
 // Unknown architecture.
 #define CONVOLVE_FUNC Convolve_C
 void SincResampler::InitializeCPUSpecificFeatures() {}
 #endif
 
 SincResampler::SincResampler(double io_sample_rate_ratio,
-                             int request_frames,
+                             size_t request_frames,
                              SincResamplerCallback* read_cb)
     : io_sample_rate_ratio_(io_sample_rate_ratio),
       read_cb_(read_cb),
       request_frames_(request_frames),
       input_buffer_size_(request_frames_ + kKernelSize),
       // Create input buffers with a 16-byte alignment for SSE optimizations.
       kernel_storage_(static_cast<float*>(
           AlignedMalloc(sizeof(float) * kKernelStorageSize, 16))),
       kernel_pre_sinc_storage_(static_cast<float*>(
           AlignedMalloc(sizeof(float) * kKernelStorageSize, 16))),
@@ skipping 45 matching lines @@
 void SincResampler::InitializeKernel() {
   // Blackman window parameters.
   static const double kAlpha = 0.16;
   static const double kA0 = 0.5 * (1.0 - kAlpha);
   static const double kA1 = 0.5;
   static const double kA2 = 0.5 * kAlpha;
 
   // Generates a set of windowed sinc() kernels.
   // We generate a range of sub-sample offsets from 0.0 to 1.0.
   const double sinc_scale_factor = SincScaleFactor(io_sample_rate_ratio_);
-  for (int offset_idx = 0; offset_idx <= kKernelOffsetCount; ++offset_idx) {
+  for (size_t offset_idx = 0; offset_idx <= kKernelOffsetCount; ++offset_idx) {
     const float subsample_offset =
         static_cast<float>(offset_idx) / kKernelOffsetCount;
 
-    for (int i = 0; i < kKernelSize; ++i) {
-      const int idx = i + offset_idx * kKernelSize;
-      const float pre_sinc =
-          static_cast<float>(M_PI * (i - kKernelSize / 2 - subsample_offset));
+    for (size_t i = 0; i < kKernelSize; ++i) {
+      const size_t idx = i + offset_idx * kKernelSize;
+      const float pre_sinc = static_cast<float>(M_PI *
+          (static_cast<int>(i) - static_cast<int>(kKernelSize / 2) -
+           subsample_offset));
       kernel_pre_sinc_storage_[idx] = pre_sinc;
 
       // Compute Blackman window, matching the offset of the sinc().
       const float x = (i - subsample_offset) / kKernelSize;
       const float window = static_cast<float>(kA0 - kA1 * cos(2.0 * M_PI * x) +
           kA2 * cos(4.0 * M_PI * x));
       kernel_window_storage_[idx] = window;
 
       // Compute the sinc with offset, then window the sinc() function and store
       // at the correct offset.
       kernel_storage_[idx] = static_cast<float>(window *
           ((pre_sinc == 0) ?
               sinc_scale_factor :
               (sin(sinc_scale_factor * pre_sinc) / pre_sinc)));
     }
   }
 }
 
 void SincResampler::SetRatio(double io_sample_rate_ratio) {
   if (fabs(io_sample_rate_ratio_ - io_sample_rate_ratio) <
       std::numeric_limits<double>::epsilon()) {
     return;
   }
 
   io_sample_rate_ratio_ = io_sample_rate_ratio;
 
   // Optimize reinitialization by reusing values which are independent of
   // |sinc_scale_factor|.  Provides a 3x speedup.
   const double sinc_scale_factor = SincScaleFactor(io_sample_rate_ratio_);
-  for (int offset_idx = 0; offset_idx <= kKernelOffsetCount; ++offset_idx) {
-    for (int i = 0; i < kKernelSize; ++i) {
-      const int idx = i + offset_idx * kKernelSize;
+  for (size_t offset_idx = 0; offset_idx <= kKernelOffsetCount; ++offset_idx) {
+    for (size_t i = 0; i < kKernelSize; ++i) {
+      const size_t idx = i + offset_idx * kKernelSize;
       const float window = kernel_window_storage_[idx];
       const float pre_sinc = kernel_pre_sinc_storage_[idx];
 
       kernel_storage_[idx] = static_cast<float>(window *
           ((pre_sinc == 0) ?
               sinc_scale_factor :
               (sin(sinc_scale_factor * pre_sinc) / pre_sinc)));
     }
   }
 }
 
-void SincResampler::Resample(int frames, float* destination) {
-  int remaining_frames = frames;
+void SincResampler::Resample(size_t frames, float* destination) {
+  size_t remaining_frames = frames;
 
   // Step (1) -- Prime the input buffer at the start of the input stream.
   if (!buffer_primed_ && remaining_frames) {
     read_cb_->Run(request_frames_, r0_);
     buffer_primed_ = true;
   }
 
   // Step (2) -- Resample!  const what we can outside of the loop for speed.  It
   // actually has an impact on ARM performance.  See inner loop comment below.
   const double current_io_ratio = io_sample_rate_ratio_;
@@ skipping 55 matching lines @@
     if (r0_ == r2_)
       UpdateRegions(true);
 
     // Step (5) -- Refresh the buffer with more input.
     read_cb_->Run(request_frames_, r0_);
   }
 }
 
 #undef CONVOLVE_FUNC
 
-int SincResampler::ChunkSize() const {
-  return static_cast<int>(block_size_ / io_sample_rate_ratio_);
+size_t SincResampler::ChunkSize() const {
+  return static_cast<size_t>(block_size_ / io_sample_rate_ratio_);
 }
 
 void SincResampler::Flush() {
   virtual_source_idx_ = 0;
   buffer_primed_ = false;
   memset(input_buffer_.get(), 0,
          sizeof(*input_buffer_.get()) * input_buffer_size_);
   UpdateRegions(false);
 }
 
 float SincResampler::Convolve_C(const float* input_ptr, const float* k1,
                                 const float* k2,
                                 double kernel_interpolation_factor) {
   float sum1 = 0;
   float sum2 = 0;
 
   // Generate a single output sample.  Unrolling this loop hurt performance in
   // local testing.
-  int n = kKernelSize;
+  size_t n = kKernelSize;
   while (n--) {
     sum1 += *input_ptr * *k1++;
     sum2 += *input_ptr++ * *k2++;
   }
 
   // Linearly interpolate the two "convolutions".
   return static_cast<float>((1.0 - kernel_interpolation_factor) * sum1 +
       kernel_interpolation_factor * sum2);
 }
 
 }  // namespace webrtc