Allow more than 2 input channels in AudioProcessing.

webrtc/common_audio/wav_file.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 105 matching lines @@
 void WavWriter::WriteSamples(const int16_t* samples, size_t num_samples) {
 #ifndef WEBRTC_ARCH_LITTLE_ENDIAN
 #error "Need to convert samples to little-endian when writing to WAV file"
 #endif
   const size_t written =
       fwrite(samples, sizeof(*samples), num_samples, file_handle_);
   CHECK_EQ(num_samples, written);
   num_samples_ += static_cast<uint32_t>(written);
   CHECK(written <= std::numeric_limits<uint32_t>::max() ||
         num_samples_ >= written);  // detect uint32_t overflow
-  CHECK(CheckWavParameters(num_channels_,

[mgraczyk, 2015/07/10 00:33:36]

This check fails when the number of channels does not divide the buffet size. It
doesn't seem correct because we may have written a chunk that splits a frame
without writing all samples. The only thing that changes here is num_samples_
and the check happens on Close. If an invalid number of total samples have been
written, we will catch it there.

[Andrew MacDonald, 2015/07/22 22:47:21]

Agreed, this check seems misplaced. 

-                           sample_rate_,
-                           kWavFormat,
-                           kBytesPerSample,
-                           num_samples_));
 }
 
 void WavWriter::WriteSamples(const float* samples, size_t num_samples) {
   static const size_t kChunksize = 4096 / sizeof(uint16_t);
   for (size_t i = 0; i < num_samples; i += kChunksize) {
     int16_t isamples[kChunksize];
     const size_t chunk = std::min(kChunksize, num_samples - i);
     FloatS16ToS16(samples + i, chunk, isamples);
     WriteSamples(isamples, chunk);
   }
@@ skipping 32 matching lines @@
   return reinterpret_cast<const webrtc::WavWriter*>(wf)->sample_rate();
 }
 
 int rtc_WavNumChannels(const rtc_WavWriter* wf) {
   return reinterpret_cast<const webrtc::WavWriter*>(wf)->num_channels();
 }
 
 uint32_t rtc_WavNumSamples(const rtc_WavWriter* wf) {
   return reinterpret_cast<const webrtc::WavWriter*>(wf)->num_samples();
 }