MultiChannelResampler does not need to recreate a ChannelProvider for every process call
https://bugs.webkit.org/show_bug.cgi?id=202982
Reviewed by Eric Carlson.
We no longer allocate a new ChannelProvider for every process call.
No observable change of behavior.
* platform/audio/MultiChannelResampler.cpp:
(WebCore::MultiChannelResampler::ChannelProvider::ChannelProvider):
(WebCore::MultiChannelResampler::ChannelProvider::setProvider):
(WebCore::MultiChannelResampler::MultiChannelResampler):
(WebCore::MultiChannelResampler::process):
* platform/audio/MultiChannelResampler.h:
git-svn-id: http://svn.webkit.org/repository/webkit/trunk@251230 268f45cc-cd09-0410-ab3c-d52691b4dbfc
diff --git a/Source/WebCore/ChangeLog b/Source/WebCore/ChangeLog
index 41fb475..71c789f 100644
--- a/Source/WebCore/ChangeLog
+++ b/Source/WebCore/ChangeLog
@@ -1,3 +1,20 @@
+2019-10-17 Youenn Fablet <youenn@apple.com>
+
+ MultiChannelResampler does not need to recreate a ChannelProvider for every process call
+ https://bugs.webkit.org/show_bug.cgi?id=202982
+
+ Reviewed by Eric Carlson.
+
+ We no longer allocate a new ChannelProvider for every process call.
+ No observable change of behavior.
+
+ * platform/audio/MultiChannelResampler.cpp:
+ (WebCore::MultiChannelResampler::ChannelProvider::ChannelProvider):
+ (WebCore::MultiChannelResampler::ChannelProvider::setProvider):
+ (WebCore::MultiChannelResampler::MultiChannelResampler):
+ (WebCore::MultiChannelResampler::process):
+ * platform/audio/MultiChannelResampler.h:
+
2019-10-17 Devin Rousso <drousso@apple.com>
Web Inspector: rework frontend agent construction to allow commands/events to be controlled by the related target's type
diff --git a/Source/WebCore/platform/audio/MultiChannelResampler.cpp b/Source/WebCore/platform/audio/MultiChannelResampler.cpp
index 5bf9ab9..5e6268d 100644
--- a/Source/WebCore/platform/audio/MultiChannelResampler.cpp
+++ b/Source/WebCore/platform/audio/MultiChannelResampler.cpp
@@ -36,21 +36,23 @@
namespace WebCore {
-namespace {
-
// ChannelProvider provides a single channel of audio data (one channel at a time) for each channel
// of data provided to us in a multi-channel provider.
-
-class ChannelProvider : public AudioSourceProvider {
+class MultiChannelResampler::ChannelProvider : public AudioSourceProvider {
+ WTF_MAKE_FAST_ALLOCATED;
public:
- ChannelProvider(AudioSourceProvider* multiChannelProvider, unsigned numberOfChannels)
- : m_multiChannelProvider(multiChannelProvider)
- , m_numberOfChannels(numberOfChannels)
- , m_currentChannel(0)
- , m_framesToProcess(0)
+ explicit ChannelProvider(unsigned numberOfChannels)
+ : m_numberOfChannels(numberOfChannels)
{
}
+ void setProvider(AudioSourceProvider* multiChannelProvider)
+ {
+ m_currentChannel = 0;
+ m_framesToProcess = 0;
+ m_multiChannelProvider = multiChannelProvider;
+ }
+
// provideInput() will be called once for each channel, starting with the first channel.
// Each time it's called, it will provide the next channel of data.
void provideInput(AudioBus* bus, size_t framesToProcess) override
@@ -83,23 +85,24 @@
}
private:
- AudioSourceProvider* m_multiChannelProvider;
+ AudioSourceProvider* m_multiChannelProvider { nullptr };
RefPtr<AudioBus> m_multiChannelBus;
- unsigned m_numberOfChannels;
- unsigned m_currentChannel;
- size_t m_framesToProcess; // Used to verify that all channels ask for the same amount.
+ unsigned m_numberOfChannels { 0 };
+ unsigned m_currentChannel { 0 };
+ size_t m_framesToProcess { 0 }; // Used to verify that all channels ask for the same amount.
};
-} // namespace
-
MultiChannelResampler::MultiChannelResampler(double scaleFactor, unsigned numberOfChannels)
: m_numberOfChannels(numberOfChannels)
+ , m_channelProvider(makeUnique<ChannelProvider>(m_numberOfChannels))
{
// Create each channel's resampler.
for (unsigned channelIndex = 0; channelIndex < numberOfChannels; ++channelIndex)
m_kernels.append(makeUnique<SincResampler>(scaleFactor));
}
+MultiChannelResampler::~MultiChannelResampler() = default;
+
void MultiChannelResampler::process(AudioSourceProvider* provider, AudioBus* destination, size_t framesToProcess)
{
ASSERT(m_numberOfChannels == destination->numberOfChannels());
@@ -107,17 +110,19 @@
// The provider can provide us with multi-channel audio data. But each of our single-channel resamplers (kernels)
// below requires a provider which provides a single unique channel of data.
// channelProvider wraps the original multi-channel provider and dishes out one channel at a time.
- ChannelProvider channelProvider(provider, m_numberOfChannels);
+ m_channelProvider->setProvider(provider);
for (unsigned channelIndex = 0; channelIndex < m_numberOfChannels; ++channelIndex) {
// Depending on the sample-rate scale factor, and the internal buffering used in a SincResampler
// kernel, this call to process() will only sometimes call provideInput() on the channelProvider.
// However, if it calls provideInput() for the first channel, then it will call it for the remaining
// channels, since they all buffer in the same way and are processing the same number of frames.
- m_kernels[channelIndex]->process(&channelProvider,
+ m_kernels[channelIndex]->process(m_channelProvider.get(),
destination->channel(channelIndex)->mutableData(),
framesToProcess);
}
+
+ m_channelProvider->setProvider(nullptr);
}
} // namespace WebCore
diff --git a/Source/WebCore/platform/audio/MultiChannelResampler.h b/Source/WebCore/platform/audio/MultiChannelResampler.h
index 6146e92..ac81bec 100644
--- a/Source/WebCore/platform/audio/MultiChannelResampler.h
+++ b/Source/WebCore/platform/audio/MultiChannelResampler.h
@@ -36,12 +36,13 @@
namespace WebCore {
class AudioBus;
-
+
class MultiChannelResampler final {
WTF_MAKE_FAST_ALLOCATED;
public:
explicit MultiChannelResampler(double scaleFactor, unsigned numberOfChannels);
-
+ ~MultiChannelResampler();
+
// Process given AudioSourceProvider for streaming applications.
void process(AudioSourceProvider*, AudioBus* destination, size_t framesToProcess);
@@ -54,6 +55,9 @@
Vector<std::unique_ptr<SincResampler>> m_kernels;
unsigned m_numberOfChannels;
+
+ class ChannelProvider;
+ std::unique_ptr<ChannelProvider> m_channelProvider;
};
} // namespace WebCore
