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/*
* Copyright (C) 2010, 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.
*/
#ifndef THIRD_PARTY_BLINK_RENDERER_MODULES_WEBAUDIO_SCRIPT_PROCESSOR_NODE_H_
#define THIRD_PARTY_BLINK_RENDERER_MODULES_WEBAUDIO_SCRIPT_PROCESSOR_NODE_H_
#include "base/gtest_prod_util.h"
#include "base/memory/scoped_refptr.h"
#include "third_party/blink/renderer/bindings/core/v8/active_script_wrappable.h"
#include "third_party/blink/renderer/modules/webaudio/audio_node.h"
#include "third_party/blink/renderer/platform/audio/audio_bus.h"
#include "third_party/blink/renderer/platform/heap/persistent.h"
#include "third_party/blink/renderer/platform/wtf/forward.h"
#include "third_party/blink/renderer/platform/wtf/vector.h"
namespace blink {
class BaseAudioContext;
class AudioBuffer;
class WaitableEvent;
// ScriptProcessorNode is an AudioNode which allows for arbitrary synthesis or
// processing directly using JavaScript. The API allows for a variable number
// of inputs and outputs, although it must have at least one input or output.
// This basic implementation supports no more than one input and output. The
// "onaudioprocess" attribute is an event listener which will get called
// periodically with an AudioProcessingEvent which has AudioBuffers for each
// input and output.
class ScriptProcessorHandler final : public AudioHandler {
public:
static scoped_refptr<ScriptProcessorHandler> Create(
AudioNode&,
float sample_rate,
size_t buffer_size,
unsigned number_of_input_channels,
unsigned number_of_output_channels);
~ScriptProcessorHandler() override;
// AudioHandler
void Process(size_t frames_to_process) override;
void Initialize() override;
size_t BufferSize() const { return buffer_size_; }
void SetChannelCount(unsigned long, ExceptionState&) override;
void SetChannelCountMode(const String&, ExceptionState&) override;
unsigned NumberOfOutputChannels() const override {
return number_of_output_channels_;
}
private:
ScriptProcessorHandler(AudioNode&,
float sample_rate,
size_t buffer_size,
unsigned number_of_input_channels,
unsigned number_of_output_channels);
double TailTime() const override;
double LatencyTime() const override;
bool RequiresTailProcessing() const final;
void FireProcessEvent(unsigned);
void FireProcessEventForOfflineAudioContext(unsigned, WaitableEvent*);
// Double buffering
unsigned DoubleBufferIndex() const { return double_buffer_index_; }
void SwapBuffers() { double_buffer_index_ = 1 - double_buffer_index_; }
unsigned double_buffer_index_;
// These Persistent don't make reference cycles including the owner
// ScriptProcessorNode.
CrossThreadPersistent<HeapVector<Member<AudioBuffer>>> input_buffers_;
CrossThreadPersistent<HeapVector<Member<AudioBuffer>>> output_buffers_;
size_t buffer_size_;
unsigned buffer_read_write_index_;
unsigned number_of_input_channels_;
unsigned number_of_output_channels_;
scoped_refptr<AudioBus> internal_input_bus_;
// Synchronize process() with fireProcessEvent().
mutable Mutex process_event_lock_;
scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
FRIEND_TEST_ALL_PREFIXES(ScriptProcessorNodeTest, BufferLifetime);
};
class ScriptProcessorNode final
: public AudioNode,
public ActiveScriptWrappable<ScriptProcessorNode> {
DEFINE_WRAPPERTYPEINFO();
USING_GARBAGE_COLLECTED_MIXIN(ScriptProcessorNode);
public:
// bufferSize must be one of the following values: 256, 512, 1024, 2048,
// 4096, 8192, 16384.
// This value controls how frequently the onaudioprocess event handler is
// called and how many sample-frames need to be processed each call.
// Lower numbers for bufferSize will result in a lower (better)
// latency. Higher numbers will be necessary to avoid audio breakup and
// glitches.
// The value chosen must carefully balance between latency and audio quality.
static ScriptProcessorNode* Create(BaseAudioContext&, ExceptionState&);
static ScriptProcessorNode* Create(BaseAudioContext&,
size_t requested_buffer_size,
ExceptionState&);
static ScriptProcessorNode* Create(BaseAudioContext&,
size_t requested_buffer_size,
unsigned number_of_input_channels,
ExceptionState&);
static ScriptProcessorNode* Create(BaseAudioContext&,
size_t requested_buffer_size,
unsigned number_of_input_channels,
unsigned number_of_output_channels,
ExceptionState&);
DEFINE_ATTRIBUTE_EVENT_LISTENER(audioprocess);
size_t bufferSize() const;
// ScriptWrappable
bool HasPendingActivity() const final;
void Trace(blink::Visitor* visitor) override { AudioNode::Trace(visitor); }
private:
ScriptProcessorNode(BaseAudioContext&,
float sample_rate,
size_t buffer_size,
unsigned number_of_input_channels,
unsigned number_of_output_channels);
};
} // namespace blink
#endif // THIRD_PARTY_BLINK_RENDERER_MODULES_WEBAUDIO_SCRIPT_PROCESSOR_NODE_H_
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