Update a ton of audio code to use size_t more correctly and in general reduce

webrtc/modules/audio_processing/intelligibility/intelligibility_enhancer.cc

 /*
  *  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.
  */
 
@@ skipping 12 matching lines @@
 #include <numeric>
 
 #include "webrtc/base/checks.h"
 #include "webrtc/common_audio/include/audio_util.h"
 #include "webrtc/common_audio/window_generator.h"
 
 namespace webrtc {
 
 namespace {
 
-const int kErbResolution = 2;
+const size_t kErbResolution = 2;
 const int kWindowSizeMs = 2;
 const int kChunkSizeMs = 10;  // Size provided by APM.
 const float kClipFreq = 200.0f;
 const float kConfigRho = 0.02f;  // Default production and interpretation SNR.
 const float kKbdAlpha = 1.5f;
 const float kLambdaBot = -1.0f;      // Extreme values in bisection
 const float kLambdaTop = -10e-18f;  // search for lamda.
 
 }  // namespace
 
 using std::complex;
 using std::max;
 using std::min;
 using VarianceType = intelligibility::VarianceArray::StepType;
 
 IntelligibilityEnhancer::TransformCallback::TransformCallback(
     IntelligibilityEnhancer* parent,
     IntelligibilityEnhancer::AudioSource source)
     : parent_(parent), source_(source) {
 }
 
 void IntelligibilityEnhancer::TransformCallback::ProcessAudioBlock(
     const complex<float>* const* in_block,
     int in_channels,
-    int frames,
+    size_t frames,
     int /* out_channels */,
     complex<float>* const* out_block) {
   DCHECK_EQ(parent_->freqs_, frames);
   for (int i = 0; i < in_channels; ++i) {
     parent_->DispatchAudio(source_, in_block[i], out_block[i]);
   }
 }
 
 IntelligibilityEnhancer::IntelligibilityEnhancer()
     : IntelligibilityEnhancer(IntelligibilityEnhancer::Config()) {
 }
 
 IntelligibilityEnhancer::IntelligibilityEnhancer(const Config& config)
     : freqs_(RealFourier::ComplexLength(
           RealFourier::FftOrder(config.sample_rate_hz * kWindowSizeMs / 1000))),
-      window_size_(1 << RealFourier::FftOrder(freqs_)),
-      chunk_length_(config.sample_rate_hz * kChunkSizeMs / 1000),
+      window_size_(static_cast<size_t>(1 << RealFourier::FftOrder(freqs_))),
+      chunk_length_(
+          static_cast<size_t>(config.sample_rate_hz * kChunkSizeMs / 1000)),
       bank_size_(GetBankSize(config.sample_rate_hz, kErbResolution)),
       sample_rate_hz_(config.sample_rate_hz),
       erb_resolution_(kErbResolution),
       num_capture_channels_(config.num_capture_channels),
       num_render_channels_(config.num_render_channels),
       analysis_rate_(config.analysis_rate),
       active_(true),
       clear_variance_(freqs_,
                       config.var_type,
                       config.var_window_size,
@@ skipping 14 matching lines @@
       kbd_window_(new float[window_size_]),
       render_callback_(this, AudioSource::kRenderStream),
       capture_callback_(this, AudioSource::kCaptureStream),
       block_count_(0),
       analysis_step_(0) {
   DCHECK_LE(config.rho, 1.0f);
 
   CreateErbBank();
 
   // Assumes all rho equal.
-  for (int i = 0; i < bank_size_; ++i) {
+  for (size_t i = 0; i < bank_size_; ++i) {
     rho_[i] = config.rho * config.rho;
   }
 
   float freqs_khz = kClipFreq / 1000.0f;
-  int erb_index = static_cast<int>(ceilf(
+  size_t erb_index = static_cast<size_t>(ceilf(
       11.17f * logf((freqs_khz + 0.312f) / (freqs_khz + 14.6575f)) + 43.0f));
-  start_freq_ = max(1, erb_index * erb_resolution_);
+  start_freq_ = std::max(static_cast<size_t>(1), erb_index * erb_resolution_);
 
   WindowGenerator::KaiserBesselDerived(kKbdAlpha, window_size_,
                                        kbd_window_.get());
   render_mangler_.reset(new LappedTransform(
       num_render_channels_, num_render_channels_, chunk_length_,
       kbd_window_.get(), window_size_, window_size_ / 2, &render_callback_));
   capture_mangler_.reset(new LappedTransform(
       num_capture_channels_, num_capture_channels_, chunk_length_,
       kbd_window_.get(), window_size_, window_size_ / 2, &capture_callback_));
 }
@@ skipping 103 matching lines @@
       lambda_top = lambda;
     }
     power_ratio = std::fabs(power * reciprocal_power_target);
     ++iters;
   }
 }
 
 void IntelligibilityEnhancer::UpdateErbGains() {
   // (ERB gain) = filterbank' * (freq gain)
   float* gains = gain_applier_.target();
-  for (int i = 0; i < freqs_; ++i) {
+  for (size_t i = 0; i < freqs_; ++i) {
     gains[i] = 0.0f;
-    for (int j = 0; j < bank_size_; ++j) {
+    for (size_t j = 0; j < bank_size_; ++j) {
       gains[i] = fmaf(filter_bank_[j][i], gains_eq_[j], gains[i]);
     }
   }
 }
 
 void IntelligibilityEnhancer::ProcessNoiseBlock(const complex<float>* in_block,
                                                 complex<float>* /*out_block*/) {
   noise_variance_.Step(in_block);
 }
 
-int IntelligibilityEnhancer::GetBankSize(int sample_rate, int erb_resolution) {
+size_t IntelligibilityEnhancer::GetBankSize(int sample_rate,
+                                            size_t erb_resolution) {
   float freq_limit = sample_rate / 2000.0f;
-  int erb_scale = ceilf(
-      11.17f * logf((freq_limit + 0.312f) / (freq_limit + 14.6575f)) + 43.0f);
+  size_t erb_scale = static_cast<size_t>(ceilf(
+      11.17f * logf((freq_limit + 0.312f) / (freq_limit + 14.6575f)) + 43.0f));
   return erb_scale * erb_resolution;
 }
 
 void IntelligibilityEnhancer::CreateErbBank() {
-  int lf = 1, rf = 4;
+  size_t lf = 1, rf = 4;
 
-  for (int i = 0; i < bank_size_; ++i) {
+  for (size_t i = 0; i < bank_size_; ++i) {
     float abs_temp = fabsf((i + 1.0f) / static_cast<float>(erb_resolution_));
     center_freqs_[i] = 676170.4f / (47.06538f - expf(0.08950404f * abs_temp));
     center_freqs_[i] -= 14678.49f;
   }
   float last_center_freq = center_freqs_[bank_size_ - 1];
-  for (int i = 0; i < bank_size_; ++i) {
+  for (size_t i = 0; i < bank_size_; ++i) {
     center_freqs_[i] *= 0.5f * sample_rate_hz_ / last_center_freq;
   }
 
-  for (int i = 0; i < bank_size_; ++i) {
+  for (size_t i = 0; i < bank_size_; ++i) {
     filter_bank_[i].resize(freqs_);
   }
 
-  for (int i = 1; i <= bank_size_; ++i) {
-    int lll, ll, rr, rrr;
-    lll = round(center_freqs_[max(1, i - lf) - 1] * freqs_ /
-                (0.5f * sample_rate_hz_));
-    ll =
-        round(center_freqs_[max(1, i) - 1] * freqs_ / (0.5f * sample_rate_hz_));
-    lll = min(freqs_, max(lll, 1)) - 1;
-    ll = min(freqs_, max(ll, 1)) - 1;
+  for (size_t i = 1; i <= bank_size_; ++i) {
+    size_t lll, ll, rr, rrr;
+    static const size_t kOne = 1;  // Avoids repeated static_cast<>s below.
+    lll = static_cast<size_t>(round(
+        center_freqs_[max(kOne, i - lf) - 1] * freqs_ /
+            (0.5f * sample_rate_hz_)));
+    ll = static_cast<size_t>(round(
+        center_freqs_[max(kOne, i) - 1] * freqs_ / (0.5f * sample_rate_hz_)));
+    lll = min(freqs_, max(lll, kOne)) - 1;
+    ll = min(freqs_, max(ll, kOne)) - 1;
 
-    rrr = round(center_freqs_[min(bank_size_, i + rf) - 1] * freqs_ /
-                (0.5f * sample_rate_hz_));
-    rr = round(center_freqs_[min(bank_size_, i + 1) - 1] * freqs_ /
-               (0.5f * sample_rate_hz_));
-    rrr = min(freqs_, max(rrr, 1)) - 1;
-    rr = min(freqs_, max(rr, 1)) - 1;
+    rrr = static_cast<size_t>(round(
+        center_freqs_[min(bank_size_, i + rf) - 1] * freqs_ /
+            (0.5f * sample_rate_hz_)));
+    rr = static_cast<size_t>(round(
+        center_freqs_[min(bank_size_, i + 1) - 1] * freqs_ /
+            (0.5f * sample_rate_hz_)));
+    rrr = min(freqs_, max(rrr, kOne)) - 1;
+    rr = min(freqs_, max(rr, kOne)) - 1;
 
     float step, element;
 
     step = 1.0f / (ll - lll);
     element = 0.0f;
-    for (int j = lll; j <= ll; ++j) {
+    for (size_t j = lll; j <= ll; ++j) {
       filter_bank_[i - 1][j] = element;
       element += step;
     }
     step = 1.0f / (rrr - rr);
     element = 1.0f;
-    for (int j = rr; j <= rrr; ++j) {
+    for (size_t j = rr; j <= rrr; ++j) {
       filter_bank_[i - 1][j] = element;
       element -= step;
     }
-    for (int j = ll; j <= rr; ++j) {
+    for (size_t j = ll; j <= rr; ++j) {
       filter_bank_[i - 1][j] = 1.0f;
     }
   }
 
   float sum;
-  for (int i = 0; i < freqs_; ++i) {
+  for (size_t i = 0; i < freqs_; ++i) {
     sum = 0.0f;
-    for (int j = 0; j < bank_size_; ++j) {
+    for (size_t j = 0; j < bank_size_; ++j) {
       sum += filter_bank_[j][i];
     }
-    for (int j = 0; j < bank_size_; ++j) {
+    for (size_t j = 0; j < bank_size_; ++j) {
       filter_bank_[j][i] /= sum;
     }
   }
 }
 
 void IntelligibilityEnhancer::SolveForGainsGivenLambda(float lambda,
-                                                       int start_freq,
+                                                       size_t start_freq,
                                                        float* sols) {
   bool quadratic = (kConfigRho < 1.0f);
   const float* var_x0 = filtered_clear_var_.get();
   const float* var_n0 = filtered_noise_var_.get();
 
-  for (int n = 0; n < start_freq; ++n) {
+  for (size_t n = 0; n < start_freq; ++n) {
     sols[n] = 1.0f;
   }
 
   // Analytic solution for optimal gains. See paper for derivation.
-  for (int n = start_freq - 1; n < bank_size_; ++n) {
+  for (size_t n = start_freq - 1; n < bank_size_; ++n) {
     float alpha0, beta0, gamma0;
     gamma0 = 0.5f * rho_[n] * var_x0[n] * var_n0[n] +
              lambda * var_x0[n] * var_n0[n] * var_n0[n];
     beta0 = lambda * var_x0[n] * (2 - rho_[n]) * var_x0[n] * var_n0[n];
     if (quadratic) {
       alpha0 = lambda * var_x0[n] * (1 - rho_[n]) * var_x0[n] * var_x0[n];
       sols[n] =
           (-beta0 - sqrtf(beta0 * beta0 - 4 * alpha0 * gamma0)) / (2 * alpha0);
     } else {
       sols[n] = -gamma0 / beta0;
     }
     sols[n] = fmax(0, sols[n]);
   }
 }
 
 void IntelligibilityEnhancer::FilterVariance(const float* var, float* result) {
-  DCHECK_GT(freqs_, 0);
-  for (int i = 0; i < bank_size_; ++i) {
+  DCHECK_GT(freqs_, 0u);
+  for (size_t i = 0; i < bank_size_; ++i) {
     result[i] = DotProduct(&filter_bank_[i][0], var, freqs_);
   }
 }
 
 float IntelligibilityEnhancer::DotProduct(const float* a,
                                           const float* b,
-                                          int length) {
+                                          size_t length) {
   float ret = 0.0f;
 
-  for (int i = 0; i < length; ++i) {
+  for (size_t i = 0; i < length; ++i) {
     ret = fmaf(a[i], b[i], ret);
   }
   return ret;
 }
 
 bool IntelligibilityEnhancer::active() const {
   return active_;
 }
 
 }  // namespace webrtc