public:
AudioMerger (int channels, boost::function<F (T)> t_to_f, boost::function<T (F)> f_to_t)
: _buffers (new AudioBuffers (channels, 0))
- , _next_out (0)
+ , _last_pull (0)
, _t_to_f (t_to_f)
, _f_to_t (f_to_t)
{}
+ /** Pull audio up to a given time; after this call, no more data can be pushed
+ * before the specified time.
+ */
TimedAudioBuffers<T>
- push (boost::shared_ptr<const AudioBuffers> audio, T time)
+ pull (T time)
{
- assert (time >= _next_out);
-
+ assert (time >= _last_pull);
+
TimedAudioBuffers<T> out;
- if (time > _next_out) {
- /* We can return some audio from our buffer; this is how many frames
- we are going to return.
- */
- F const to_return = _t_to_f (time - _next_out);
- out.audio.reset (new AudioBuffers (_buffers->channels(), to_return));
- /* And this is how many we will get from our buffer */
- F const to_return_from_buffers = min (to_return, _buffers->frames ());
-
- /* Copy the data that we have to the back end of the return buffer */
- out.audio->copy_from (_buffers.get(), to_return_from_buffers, 0, to_return - to_return_from_buffers);
- /* Silence any gap at the start */
- out.audio->make_silent (0, to_return - to_return_from_buffers);
-
- out.time = _next_out;
- _next_out += _f_to_t (to_return);
-
- /* And remove the data we're returning from our buffers */
- if (_buffers->frames() > to_return_from_buffers) {
- _buffers->move (to_return_from_buffers, 0, _buffers->frames() - to_return_from_buffers);
- }
- _buffers->set_frames (_buffers->frames() - to_return_from_buffers);
+ F const to_return = _t_to_f (time - _last_pull);
+ out.audio.reset (new AudioBuffers (_buffers->channels(), to_return));
+ /* And this is how many we will get from our buffer */
+ F const to_return_from_buffers = min (to_return, _buffers->frames ());
+
+ /* Copy the data that we have to the back end of the return buffer */
+ out.audio->copy_from (_buffers.get(), to_return_from_buffers, 0, to_return - to_return_from_buffers);
+ /* Silence any gap at the start */
+ out.audio->make_silent (0, to_return - to_return_from_buffers);
+
+ out.time = _last_pull;
+ _last_pull = time;
+
+ /* And remove the data we're returning from our buffers */
+ if (_buffers->frames() > to_return_from_buffers) {
+ _buffers->move (to_return_from_buffers, 0, _buffers->frames() - to_return_from_buffers);
}
+ _buffers->set_frames (_buffers->frames() - to_return_from_buffers);
+
+ return out;
+ }
+
+ void
+ push (boost::shared_ptr<const AudioBuffers> audio, T time)
+ {
+ assert (time >= _last_pull);
- /* Now accumulate the new audio into our buffers */
F frame = _t_to_f (time);
- F after = max (_buffers->frames(), frame + audio->frames() - _t_to_f (_next_out));
+ F after = max (_buffers->frames(), frame + audio->frames() - _t_to_f (_last_pull));
_buffers->ensure_size (after);
- _buffers->accumulate_frames (audio.get(), 0, frame - _t_to_f (_next_out), audio->frames ());
+ _buffers->accumulate_frames (audio.get(), 0, frame - _t_to_f (_last_pull), audio->frames ());
_buffers->set_frames (after);
-
- return out;
}
F min (F a, int b)
if (_buffers->frames() == 0) {
return TimedAudioBuffers<T> ();
}
-
- return TimedAudioBuffers<T> (_buffers, _next_out);
+
+ return TimedAudioBuffers<T> (_buffers, _last_pull);
+ }
+
+ void
+ clear (DCPTime t)
+ {
+ _last_pull = t;
+ _buffers.reset (new AudioBuffers (_buffers->channels(), 0));
}
private:
boost::shared_ptr<AudioBuffers> _buffers;
- T _next_out;
+ T _last_pull;
boost::function<F (T)> _t_to_f;
boost::function<T (F)> _f_to_t;
};