Line data    Source code

       1             : /*
       2             :  *  Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
       3             :  *
       4             :  *  Use of this source code is governed by a BSD-style license
       5             :  *  that can be found in the LICENSE file in the root of the source
       6             :  *  tree. An additional intellectual property rights grant can be found
       7             :  *  in the file PATENTS.  All contributing project authors may
       8             :  *  be found in the AUTHORS file in the root of the source tree.
       9             :  */
      10             : 
      11             : #include "webrtc/modules/audio_processing/splitting_filter.h"
      12             : 
      13             : #include "webrtc/base/checks.h"
      14             : #include "webrtc/common_audio/signal_processing/include/signal_processing_library.h"
      15             : #include "webrtc/common_audio/channel_buffer.h"
      16             : 
      17             : namespace webrtc {
      18             : 
      19           0 : SplittingFilter::SplittingFilter(size_t num_channels,
      20             :                                  size_t num_bands,
      21           0 :                                  size_t num_frames)
      22           0 :     : num_bands_(num_bands) {
      23           0 :   RTC_CHECK(num_bands_ == 2 || num_bands_ == 3);
      24           0 :   if (num_bands_ == 2) {
      25           0 :     two_bands_states_.resize(num_channels);
      26           0 :   } else if (num_bands_ == 3) {
      27           0 :     for (size_t i = 0; i < num_channels; ++i) {
      28           0 :       three_band_filter_banks_.push_back(std::unique_ptr<ThreeBandFilterBank>(
      29           0 :           new ThreeBandFilterBank(num_frames)));
      30             :     }
      31             :   }
      32           0 : }
      33             : 
      34             : SplittingFilter::~SplittingFilter() = default;
      35             : 
      36           0 : void SplittingFilter::Analysis(const IFChannelBuffer* data,
      37             :                                IFChannelBuffer* bands) {
      38           0 :   RTC_DCHECK_EQ(num_bands_, bands->num_bands());
      39           0 :   RTC_DCHECK_EQ(data->num_channels(), bands->num_channels());
      40           0 :   RTC_DCHECK_EQ(data->num_frames(),
      41           0 :                 bands->num_frames_per_band() * bands->num_bands());
      42           0 :   if (bands->num_bands() == 2) {
      43           0 :     TwoBandsAnalysis(data, bands);
      44           0 :   } else if (bands->num_bands() == 3) {
      45           0 :     ThreeBandsAnalysis(data, bands);
      46             :   }
      47           0 : }
      48             : 
      49           0 : void SplittingFilter::Synthesis(const IFChannelBuffer* bands,
      50             :                                 IFChannelBuffer* data) {
      51           0 :   RTC_DCHECK_EQ(num_bands_, bands->num_bands());
      52           0 :   RTC_DCHECK_EQ(data->num_channels(), bands->num_channels());
      53           0 :   RTC_DCHECK_EQ(data->num_frames(),
      54           0 :                 bands->num_frames_per_band() * bands->num_bands());
      55           0 :   if (bands->num_bands() == 2) {
      56           0 :     TwoBandsSynthesis(bands, data);
      57           0 :   } else if (bands->num_bands() == 3) {
      58           0 :     ThreeBandsSynthesis(bands, data);
      59             :   }
      60           0 : }
      61             : 
      62           0 : void SplittingFilter::TwoBandsAnalysis(const IFChannelBuffer* data,
      63             :                                        IFChannelBuffer* bands) {
      64           0 :   RTC_DCHECK_EQ(two_bands_states_.size(), data->num_channels());
      65           0 :   for (size_t i = 0; i < two_bands_states_.size(); ++i) {
      66           0 :     WebRtcSpl_AnalysisQMF(data->ibuf_const()->channels()[i],
      67             :                           data->num_frames(),
      68           0 :                           bands->ibuf()->channels(0)[i],
      69           0 :                           bands->ibuf()->channels(1)[i],
      70           0 :                           two_bands_states_[i].analysis_state1,
      71           0 :                           two_bands_states_[i].analysis_state2);
      72             :   }
      73           0 : }
      74             : 
      75           0 : void SplittingFilter::TwoBandsSynthesis(const IFChannelBuffer* bands,
      76             :                                         IFChannelBuffer* data) {
      77           0 :   RTC_DCHECK_LE(data->num_channels(), two_bands_states_.size());
      78           0 :   for (size_t i = 0; i < data->num_channels(); ++i) {
      79           0 :     WebRtcSpl_SynthesisQMF(bands->ibuf_const()->channels(0)[i],
      80           0 :                            bands->ibuf_const()->channels(1)[i],
      81             :                            bands->num_frames_per_band(),
      82           0 :                            data->ibuf()->channels()[i],
      83           0 :                            two_bands_states_[i].synthesis_state1,
      84           0 :                            two_bands_states_[i].synthesis_state2);
      85             :   }
      86           0 : }
      87             : 
      88           0 : void SplittingFilter::ThreeBandsAnalysis(const IFChannelBuffer* data,
      89             :                                          IFChannelBuffer* bands) {
      90           0 :   RTC_DCHECK_EQ(three_band_filter_banks_.size(), data->num_channels());
      91           0 :   for (size_t i = 0; i < three_band_filter_banks_.size(); ++i) {
      92           0 :     three_band_filter_banks_[i]->Analysis(data->fbuf_const()->channels()[i],
      93             :                                           data->num_frames(),
      94           0 :                                           bands->fbuf()->bands(i));
      95             :   }
      96           0 : }
      97             : 
      98           0 : void SplittingFilter::ThreeBandsSynthesis(const IFChannelBuffer* bands,
      99             :                                           IFChannelBuffer* data) {
     100           0 :   RTC_DCHECK_LE(data->num_channels(), three_band_filter_banks_.size());
     101           0 :   for (size_t i = 0; i < data->num_channels(); ++i) {
     102           0 :     three_band_filter_banks_[i]->Synthesis(bands->fbuf_const()->bands(i),
     103             :                                            bands->num_frames_per_band(),
     104           0 :                                            data->fbuf()->channels()[i]);
     105             :   }
     106           0 : }
     107             : 
     108             : }  // namespace webrtc