void ChannelMergerNode::process(size_t framesToProcess)
{
AudioNodeOutput* output = this->output(0);
ASSERT(output);
ASSERT_UNUSED(framesToProcess, framesToProcess == output->bus()->length());
// Output bus not updated yet, so just output silence.
if (m_desiredNumberOfOutputChannels != output->numberOfChannels()) {
output->bus()->zero();
return;
}
// Merge all the channels from all the inputs into one output.
unsigned outputChannelIndex = 0;
for (unsigned i = 0; i < numberOfInputs(); ++i) {
AudioNodeInput* input = this->input(i);
if (input->isConnected()) {
unsigned numberOfInputChannels = input->bus()->numberOfChannels();
// Merge channels from this particular input.
for (unsigned j = 0; j < numberOfInputChannels; ++j) {
AudioChannel* inputChannel = input->bus()->channel(j);
AudioChannel* outputChannel = output->bus()->channel(outputChannelIndex);
outputChannel->copyFrom(inputChannel);
++outputChannelIndex;
}
}
}
ASSERT(outputChannelIndex == output->numberOfChannels());
}
unsigned AudioNodeInput::numberOfChannels() const
{
// Find the number of channels of the connection with the largest number of channels.
unsigned maxChannels = 1; // one channel is the minimum allowed
for (HashSet<AudioNodeOutput*>::iterator i = m_outputs.begin(); i != m_outputs.end(); ++i) {
AudioNodeOutput* output = *i;
maxChannels = max(maxChannels, output->bus()->numberOfChannels());
}
return maxChannels;
}
void ChannelMergerNode::process(size_t framesToProcess)
{
AudioNodeOutput* output = this->output(0);
ASSERT(output);
ASSERT_UNUSED(framesToProcess, framesToProcess == output->bus()->length());
// Output bus not updated yet, so just output silence.
if (m_desiredNumberOfOutputChannels != output->numberOfChannels()) {
output->bus()->zero();
return;
}
// Merge all the channels from all the inputs into one output.
unsigned outputChannelIndex = 0;
unsigned maxAllowedOutputChannels = output->numberOfChannels();
for (unsigned i = 0; i < numberOfInputs(); ++i) {
AudioNodeInput* input = this->input(i);
if (input->isConnected()) {
unsigned numberOfInputChannels = input->bus()->numberOfChannels();
// Merge channels from this particular input, but be careful not to exceed the number of
// output channels. (This can happen if there are many inputs with each input
// containing many channels.)
for (unsigned j = 0; j < numberOfInputChannels; ++j) {
if (outputChannelIndex < maxAllowedOutputChannels) {
AudioChannel* inputChannel = input->bus()->channel(j);
AudioChannel* outputChannel = output->bus()->channel(outputChannelIndex);
outputChannel->copyFrom(inputChannel);
++outputChannelIndex;
}
}
}
if (outputChannelIndex >= maxAllowedOutputChannels)
break;
}
ASSERT(outputChannelIndex == output->numberOfChannels());
}