Don't overlap simultaneous video content in the timeline. Fix keep-aligned for separ...

[dcpomatic.git] / src / lib / audio_merger.h

diff --git a/src/lib/audio_merger.h b/src/lib/audio_merger.h
index afb21871bd0c72f031acae149ff69eaa7aa11c23..226601e0ec61dffc92726bd8f98bbd976f21e9ad 100644 (file)
--- a/src/lib/audio_merger.h
+++ b/src/lib/audio_merger.h
@@ -26,50 +26,51 @@ class AudioMerger
 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);
-
                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);
+               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);
 
-                       out.time = _next_out;
-                       _next_out += _f_to_t (to_return);
+               return out;
+       }
 
-                       /* 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);
-               }
+       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)
@@ -97,12 +98,12 @@ public:
                        return TimedAudioBuffers<T> ();
                }
                
-               return TimedAudioBuffers<T> (_buffers, _next_out);
+               return TimedAudioBuffers<T> (_buffers, _last_pull);
        }
        
 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;
 };