Update audio code to use size_t more correctly,

webrtc/modules/audio_coding/neteq/preemptive_expand.cc

 /*
  *  Copyright (c) 2012 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/modules/audio_coding/neteq/preemptive_expand.h"
 
 #include <algorithm>  // min, max
 
 #include "webrtc/common_audio/signal_processing/include/signal_processing_library.h"
 
 namespace webrtc {
 
 PreemptiveExpand::ReturnCodes PreemptiveExpand::Process(
     const int16_t* input,
-    int input_length,
-    int old_data_length,
+    size_t input_length,
+    size_t old_data_length,
     AudioMultiVector* output,
-    int16_t* length_change_samples) {
+    size_t* length_change_samples) {
   old_data_length_per_channel_ = old_data_length;
   // Input length must be (almost) 30 ms.
   // Also, the new part must be at least |overlap_samples_| elements.
   static const int k15ms = 120;  // 15 ms = 120 samples at 8 kHz sample rate.
   if (num_channels_ == 0 ||
       input_length / num_channels_ < (2 * k15ms - 1) * fs_mult_ ||
       old_data_length >= input_length / num_channels_ - overlap_samples_) {
     // Length of input data too short to do preemptive expand. Simply move all
     // data from input to output.
     output->PushBackInterleaved(input, input_length);
     return kError;
   }
   const bool kFastMode = false;  // Fast mode is not available for PE Expand.
   return TimeStretch::Process(input, input_length, kFastMode, output,
                               length_change_samples);
 }
 
 void PreemptiveExpand::SetParametersForPassiveSpeech(size_t len,
                                                      int16_t* best_correlation,
-                                                     int* peak_index) const {
+                                                     size_t* peak_index) const {
   // When the signal does not contain any active speech, the correlation does
   // not matter. Simply set it to zero.
   *best_correlation = 0;
 
   // For low energy expansion, the new data can be less than 15 ms,
   // but we must ensure that best_correlation is not larger than the length of
   // the new data.
   // but we must ensure that best_correlation is not larger than the new data.
   *peak_index = std::min(*peak_index,
-                         static_cast<int>(len - old_data_length_per_channel_));
+                         len - old_data_length_per_channel_);
 }
 
 PreemptiveExpand::ReturnCodes PreemptiveExpand::CheckCriteriaAndStretch(
     const int16_t* input,
     size_t input_length,
     size_t peak_index,
     int16_t best_correlation,
     bool active_speech,
     bool /*fast_mode*/,
     AudioMultiVector* output) const {
   // Pre-calculate common multiplication with |fs_mult_|.
   // 120 corresponds to 15 ms.
-  int fs_mult_120 = fs_mult_ * 120;
-  assert(old_data_length_per_channel_ >= 0);  // Make sure it's been set.
+  size_t fs_mult_120 = fs_mult_ * 120;

[hlundin-webrtc, 2015/08/10 11:30:01]

Keep the int.

[Peter Kasting, 2015/08/17 22:49:47]

This is an example of a place where I left |fs_mult_120| as size_t.  See how its
use below indicates that its units are the same as those for
|old_data_length_per_channel_| (which should definitely be a size_t).

[hlundin-webrtc, 2015/08/18 07:19:18]

Acknowledged.

   // Check for strong correlation (>0.9 in Q14) and at least 15 ms new data,
   // or passive speech.
   if (((best_correlation > kCorrelationThreshold) &&
       (old_data_length_per_channel_ <= fs_mult_120)) ||
       !active_speech) {
     // Do accelerate operation by overlap add.
 
     // Set length of the first part, not to be modified.
     size_t unmodified_length = std::max(old_data_length_per_channel_,
                                         fs_mult_120);
@@ skipping 21 matching lines @@
     // Accelerate not allowed. Simply move all data from decoded to outData.
     output->PushBackInterleaved(input, input_length);
     return kNoStretch;
   }
 }
 
 PreemptiveExpand* PreemptiveExpandFactory::Create(
     int sample_rate_hz,
     size_t num_channels,
     const BackgroundNoise& background_noise,
-    int overlap_samples) const {
+    size_t overlap_samples) const {
   return new PreemptiveExpand(
       sample_rate_hz, num_channels, background_noise, overlap_samples);
 }
 
 }  // namespace webrtc