third_party/WebKit/Source/modules/webaudio/BiquadFilterNode.cpp

/*
 * Copyright (C) 2011, Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1.  Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2.  Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 */

#include "modules/webaudio/BiquadFilterNode.h"

#include "modules/webaudio/AudioBasicProcessorHandler.h"
#include "modules/webaudio/BiquadFilterOptions.h"
#include "platform/Histogram.h"
#include "wtf/PtrUtil.h"

namespace blink {

BiquadFilterNode::BiquadFilterNode(BaseAudioContext& context)
    : AudioNode(context),
      m_frequency(AudioParam::create(context,
                                     ParamTypeBiquadFilterFrequency,
                                     350.0,
                                     0,
                                     context.sampleRate() / 2)),
      m_q(AudioParam::create(context, ParamTypeBiquadFilterQ, 1.0)),
      m_gain(AudioParam::create(context, ParamTypeBiquadFilterGain, 0.0)),
      m_detune(AudioParam::create(context, ParamTypeBiquadFilterDetune, 0.0)) {
  setHandler(AudioBasicProcessorHandler::create(
      AudioHandler::NodeTypeBiquadFilter, *this, context.sampleRate(),
      wrapUnique(new BiquadProcessor(context.sampleRate(), 1,
                                     m_frequency->handler(), m_q->handler(),
                                     m_gain->handler(), m_detune->handler()))));

  // Explicitly set the filter type so that any histograms get updated with the default value.
  // Otherwise, the histogram won't ever show it.
  setType("lowpass");
}

BiquadFilterNode* BiquadFilterNode::create(BaseAudioContext& context,
                                           ExceptionState& exceptionState) {
  DCHECK(isMainThread());

  if (context.isContextClosed()) {
    context.throwExceptionForClosedState(exceptionState);
    return nullptr;
  }

  return new BiquadFilterNode(context);
}

BiquadFilterNode* BiquadFilterNode::create(BaseAudioContext* context,
                                           const BiquadFilterOptions& options,
                                           ExceptionState& exceptionState) {
  BiquadFilterNode* node = create(*context, exceptionState);

  if (!node)
    return nullptr;

  node->handleChannelOptions(options, exceptionState);

  if (options.hasType())
    node->setType(options.type());
  if (options.hasQ())
    node->q()->setValue(options.Q());
  if (options.hasDetune())
    node->detune()->setValue(options.detune());
  if (options.hasFrequency())
    node->frequency()->setValue(options.frequency());
  if (options.hasGain())
    node->gain()->setValue(options.gain());

  return node;
}

DEFINE_TRACE(BiquadFilterNode) {
  visitor->trace(m_frequency);
  visitor->trace(m_q);
  visitor->trace(m_gain);
  visitor->trace(m_detune);
  AudioNode::trace(visitor);
}

BiquadProcessor* BiquadFilterNode::getBiquadProcessor() const {
  return static_cast<BiquadProcessor*>(
      static_cast<AudioBasicProcessorHandler&>(handler()).processor());
}

String BiquadFilterNode::type() const {
  switch (const_cast<BiquadFilterNode*>(this)->getBiquadProcessor()->type()) {
    case BiquadProcessor::LowPass:
      return "lowpass";
    case BiquadProcessor::HighPass:
      return "highpass";
    case BiquadProcessor::BandPass:
      return "bandpass";
    case BiquadProcessor::LowShelf:
      return "lowshelf";
    case BiquadProcessor::HighShelf:
      return "highshelf";
    case BiquadProcessor::Peaking:
      return "peaking";
    case BiquadProcessor::Notch:
      return "notch";
    case BiquadProcessor::Allpass:
      return "allpass";
    default:
      ASSERT_NOT_REACHED();
      return "lowpass";
  }
}

void BiquadFilterNode::setType(const String& type) {
  // For the Q histogram, we need to change the name of the AudioParam for the lowpass and
  // highpass filters so we know to count the Q value when it is set. And explicitly set the value
  // to itself so the histograms know the initial value.

  if (type == "lowpass") {
    setType(BiquadProcessor::LowPass);
    m_q->setParamType(ParamTypeBiquadFilterQLowpass);
    m_q->setValue(m_q->value());
  } else if (type == "highpass") {
    setType(BiquadProcessor::HighPass);
    m_q->setParamType(ParamTypeBiquadFilterQHighpass);
    m_q->setValue(m_q->value());
  } else if (type == "bandpass") {
    setType(BiquadProcessor::BandPass);
  } else if (type == "lowshelf") {
    setType(BiquadProcessor::LowShelf);
  } else if (type == "highshelf") {
    setType(BiquadProcessor::HighShelf);
  } else if (type == "peaking") {
    setType(BiquadProcessor::Peaking);
  } else if (type == "notch") {
    setType(BiquadProcessor::Notch);
  } else if (type == "allpass") {
    setType(BiquadProcessor::Allpass);
  }
}

bool BiquadFilterNode::setType(unsigned type) {
  if (type > BiquadProcessor::Allpass)
    return false;

  DEFINE_STATIC_LOCAL(
      EnumerationHistogram, filterTypeHistogram,
      ("WebAudio.BiquadFilter.Type", BiquadProcessor::Allpass + 1));
  filterTypeHistogram.count(type);

  getBiquadProcessor()->setType(static_cast<BiquadProcessor::FilterType>(type));
  return true;
}

void BiquadFilterNode::getFrequencyResponse(const DOMFloat32Array* frequencyHz,
                                            DOMFloat32Array* magResponse,
                                            DOMFloat32Array* phaseResponse) {
  DCHECK(frequencyHz);
  DCHECK(magResponse);
  DCHECK(phaseResponse);

  int n = std::min(frequencyHz->length(),
                   std::min(magResponse->length(), phaseResponse->length()));
  if (n)
    getBiquadProcessor()->getFrequencyResponse(
        n, frequencyHz->data(), magResponse->data(), phaseResponse->data());
}

}  // namespace blink