reverb_convolver.cc | Explore in Territory

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#include "third_party/blink/renderer/platform/audio/reverb_convolver.h"

#include <memory>
#include <utility>

#include "base/location.h"
#include "third_party/blink/renderer/platform/audio/audio_bus.h"
#include "third_party/blink/renderer/platform/audio/vector_math.h"
#include "third_party/blink/renderer/platform/scheduler/public/post_cross_thread_task.h"
#include "third_party/blink/renderer/platform/wtf/cross_thread_functional.h"

namespace blink {

const int kInputBufferSize = …;

// We only process the leading portion of the impulse response in the real-time
// thread.  We don't exceed this length.  It turns out then, that the
// background thread has about 278msec of scheduling slop.  Empirically, this
// has been found to be a good compromise between giving enough time for
// scheduling slop, while still minimizing the amount of processing done in the
// primary (high-priority) thread.  This was found to be a good value on Mac OS
// X, and may work well on other platforms as well, assuming the very rough
// scheduling latencies are similar on these time-scales.  Of course, this code
// may need to be tuned for individual platforms if this assumption is found to
// be incorrect.
const size_t kRealtimeFrameLimit = …;  // ~278msec @ 44.1KHz

const unsigned kMinFFTSize = …;
const unsigned kMaxRealtimeFFTSize = …;

ReverbConvolver::ReverbConvolver(AudioChannel* impulse_response,
                                 unsigned render_slice_size,
                                 unsigned max_fft_size,
                                 size_t convolver_render_phase,
                                 bool use_background_threads,
                                 float scale)
    : … { … }

ReverbConvolver::~ReverbConvolver() { … }

void ReverbConvolver::ProcessInBackground() { … }

void ReverbConvolver::Process(const AudioChannel* source_channel,
                              AudioChannel* destination_channel,
                              uint32_t frames_to_process) { … }

void ReverbConvolver::Reset() { … }

size_t ReverbConvolver::LatencyFrames() const { … }

}  // namespace blink
chromium/third_party/blink/renderer/platform/audio/reverb_convolver.cc
