Reland: Drop the 16kHz sample rate restriction on AECM and zero out higher bands

webrtc/modules/audio_processing/echo_control_mobile_impl.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.
  */
 
@@ skipping 188 matching lines @@
           clean,
           audio->split_bands(i)[kBand0To8kHz],
           audio->num_frames_per_band(),
           apm_->stream_delay_ms());
 
       if (err != AudioProcessing::kNoError)
         return MapError(err);
 
       handle_index++;
     }
+    for (size_t band = 1u; band < audio->num_bands(); ++band) {
+      memset(audio->split_bands(i)[band],
+             0,
+             audio->num_frames_per_band() *
+                 sizeof(audio->split_bands(i)[band][0]));
+    }
   }
 
   return AudioProcessing::kNoError;
 }
 
 int EchoControlMobileImpl::Enable(bool enable) {
   // Ensure AEC and AECM are not both enabled.
   rtc::CritScope cs_render(crit_render_);
   rtc::CritScope cs_capture(crit_capture_);
   // The is_enabled call is safe from a deadlock perspective
@@ skipping 86 matching lines @@
   return AudioProcessing::kNoError;
 }
 
 int EchoControlMobileImpl::Initialize() {
   {
     rtc::CritScope cs_capture(crit_capture_);
     if (!is_component_enabled()) {
       return AudioProcessing::kNoError;
     }
   }
 

[peah-webrtc, 2016/03/11 11:34:39]

Regarding proc_split_sample_rate_hz(), can that ever be higher than 16 kHz?
Furthermore, can that be anything other than 16 kHz?

[aluebs-webrtc, 2016/03/11 13:27:05]

As it is today, it is always 16kHz except when the sample_rate is 8kHz, then the
split_sample_rate is also 8kHz.

[peah-webrtc, 2016/03/11 21:37:28]

We really need to change the names of these functions. In my mind, split rate
relates to the rate of the split signal. And the 8 and 16 kHz are not split so
then the name is quite misleading.

[aluebs-webrtc, 2016/03/14 17:30:40]

I agree it probably can have a better name, but the rename should be done in a
separate CL.

-  if (apm_->proc_sample_rate_hz() > AudioProcessing::kSampleRate16kHz) {
-    LOG(LS_ERROR) << "AECM only supports 16 kHz or lower sample rates";
+  if (apm_->proc_split_sample_rate_hz() > AudioProcessing::kSampleRate16kHz) {
+    LOG(LS_ERROR) << "AECM only supports 16 kHz or lower split sample rates";
     return AudioProcessing::kBadSampleRateError;
   }
 
   int err = ProcessingComponent::Initialize();
   if (err != AudioProcessing::kNoError) {
     return err;
   }
 
   AllocateRenderQueue();
 
@@ skipping 35 matching lines @@
   // This method is only called in a non-concurrent manner during APM
   // destruction.
   WebRtcAecm_Free(static_cast<Handle*>(handle));
 }
 
 int EchoControlMobileImpl::InitializeHandle(void* handle) const {
   rtc::CritScope cs_render(crit_render_);
   rtc::CritScope cs_capture(crit_capture_);
   assert(handle != NULL);
   Handle* my_handle = static_cast<Handle*>(handle);
-  if (WebRtcAecm_Init(my_handle, apm_->proc_sample_rate_hz()) != 0) {
+  if (WebRtcAecm_Init(my_handle, apm_->proc_split_sample_rate_hz()) != 0) {
     return GetHandleError(my_handle);
   }
   if (external_echo_path_ != NULL) {
     if (WebRtcAecm_InitEchoPath(my_handle,
                                 external_echo_path_,
                                 echo_path_size_bytes()) != 0) {
       return GetHandleError(my_handle);
     }
   }
 
@@ skipping 14 matching lines @@
   // Not locked as it only relies on APM public API which is threadsafe.
   return apm_->num_output_channels() * apm_->num_reverse_channels();
 }
 
 int EchoControlMobileImpl::GetHandleError(void* handle) const {
   // Not locked as it does not rely on anything in the state.
   assert(handle != NULL);
   return AudioProcessing::kUnspecifiedError;
 }
 }  // namespace webrtc