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Added pausing, rewind, fast forward, and playing (and different speeds). Still a bit buggy and experimental with fast forward and rewinding (due to seek bugs in readers).

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Jonathan Thomas
2014-03-23 01:12:29 -05:00
parent 2ba83486c9
commit a77de842e4
13 changed files with 346 additions and 54 deletions
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48
src/AudioReaderSource.cpp
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@@ -33,7 +33,7 @@ using namespace openshot;
// Constructor that reads samples from a reader
AudioReaderSource::AudioReaderSource(ReaderBase *audio_reader, int64 starting_frame_number, int buffer_size)
: reader(audio_reader), frame_number(starting_frame_number), original_frame_number(starting_frame_number),
size(buffer_size), position(0), frame_position(0), estimated_frame(0) {
size(buffer_size), position(0), frame_position(0), estimated_frame(0), speed(1) {
// Initialize an audio buffer (based on reader)
buffer = new juce::AudioSampleBuffer(reader->info.channels, size);
@@ -79,13 +79,14 @@ void AudioReaderSource::GetMoreSamplesFromReader() {
position = 0;
// Loop through frames until buffer filled
while (amount_needed > 0) {
while (amount_needed > 0 && speed != 0) {
// Get the next frame (if position is zero)
if (frame_position == 0) {
try {
// Get frame object
frame = reader->GetFrameSafe(frame_number++);
frame = reader->GetFrameSafe(frame_number);
frame_number = frame_number + speed;
} catch (const ReaderClosed & e) {
break;
@@ -110,7 +111,12 @@ void AudioReaderSource::GetMoreSamplesFromReader() {
// Load all of its samples into the buffer
for (int channel = 0; channel < new_buffer->getNumChannels(); channel++)
new_buffer->addFrom(channel, position, *frame->GetAudioSampleBuffer(), channel, frame_position, amount_to_copy);
if (speed >= 0)
// playback normal
new_buffer->addFrom(channel, position, *frame->GetAudioSampleBuffer(), channel, frame_position, amount_to_copy);
else
// reverse playback
new_buffer->addFrom(channel, position, *reverse_buffer(frame->GetAudioSampleBuffer()), channel, frame_position, amount_to_copy);
// Adjust remaining samples
position += amount_to_copy;
@@ -131,6 +137,37 @@ void AudioReaderSource::GetMoreSamplesFromReader() {
position = 0;
}
// Reverse an audio buffer
juce::AudioSampleBuffer* AudioReaderSource::reverse_buffer(juce::AudioSampleBuffer* buffer)
{
int number_of_samples = buffer->getNumSamples();
int channels = buffer->getNumChannels();
// Reverse array (create new buffer to hold the reversed version)
AudioSampleBuffer *reversed = new juce::AudioSampleBuffer(channels, number_of_samples);
reversed->clear();
for (int channel = 0; channel < channels; channel++)
{
int n=0;
for (int s = number_of_samples - 1; s >= 0; s--, n++)
reversed->getSampleData(channel)[n] = buffer->getSampleData(channel)[s];
}
// Copy the samples back to the original array
buffer->clear();
// Loop through channels, and get audio samples
for (int channel = 0; channel < channels; channel++)
// Get the audio samples for this channel
buffer->addFrom(channel, 0, reversed->getSampleData(channel), number_of_samples, 1.0f);
delete reversed;
reversed = NULL;
// return pointer or passed in object (so this method can be chained together)
return buffer;
}
// Get the next block of audio samples
void AudioReaderSource::getNextAudioBlock (const AudioSourceChannelInfo& info)
{
@@ -182,7 +219,8 @@ void AudioReaderSource::getNextAudioBlock (const AudioSourceChannelInfo& info)
// Adjust estimate frame number (the estimated frame number that is being played)
estimated_samples_per_frame = Frame::GetSamplesPerFrame(estimated_frame, reader->info.fps, reader->info.sample_rate);
estimated_frame += double(info.numSamples) / double(estimated_samples_per_frame);
if (speed != 0)
estimated_frame += double(info.numSamples) / double(estimated_samples_per_frame);
}
}