First cut.

1 files changed, 116 insertions, 32 deletions

diff --git a/src/lib/matcher.cc b/src/lib/matcher.cc
index 3a513b24e..70a9b2a85 100644
--- a/src/lib/matcher.cc
+++ b/src/lib/matcher.cc
@@ -24,6 +24,8 @@
 #include "i18n.h"
 
 using std::min;
+using std::cout;
+using std::list;
 using boost::shared_ptr;
 
 Matcher::Matcher (Log* log, int sample_rate, float frames_per_second)
@@ -37,22 +39,72 @@ Matcher::Matcher (Log* log, int sample_rate, float frames_per_second)
 }
 
 void
-Matcher::process_video (boost::shared_ptr<Image> i, bool same, boost::shared_ptr<Subtitle> s, double)
+Matcher::process_video (boost::shared_ptr<Image> image, bool same, boost::shared_ptr<Subtitle> sub, double t)
 {
-	Video (i, same, s);
-	_video_frames++;
+	_pixel_format = image->pixel_format ();
+	_size = image->size ();
 
-	_pixel_format = i->pixel_format ();
-	_size = i->size ();
+	if (!_first_input) {
+		_first_input = t;
+	}
+	
+	if (_audio_frames == 0 && _pending_audio.empty ()) {
+		/* No audio yet; we must postpone this frame until we have some */
+		_pending_video.push_back (VideoRecord (image, same, sub, t));
+	} else if (!_pending_audio.empty() && _pending_video.empty ()) {
+		/* First video since we got audio */
+		_pending_video.push_back (VideoRecord (image, same, sub, t));
+		fix_start ();
+	} else {
+		/* Normal running */
+
+		/* Difference between where this video is and where it should be */
+		double const delta = t - _first_input.get() - _video_frames / _frames_per_second;
+		double const one_frame = 1 / _frames_per_second;
+
+		if (delta > one_frame) {
+			/* Insert frames to make up the difference */
+			int const extra = rint (delta / one_frame);
+			for (int i = 0; i < extra; ++i) {
+				repeat_last_video ();
+				_log->log (String::compose ("Extra video frame inserted at %1s", _video_frames / _frames_per_second));
+			}
+		}
+
+		if (delta > -one_frame) {
+			Video (image, same, sub);
+			++_video_frames;
+		} else {
+			/* We are omitting a frame to keep things right */
+			_log->log (String::compose ("Frame removed at %1s", t));
+		}
+	}
+		
+	_last_image = image;
+	_last_subtitle = sub;
 }
 
 void
-Matcher::process_audio (boost::shared_ptr<AudioBuffers> b, double)
+Matcher::process_audio (boost::shared_ptr<AudioBuffers> b, double t)
 {
-	Audio (b);
-	_audio_frames += b->frames ();
-
 	_channels = b->channels ();
+	
+	if (!_first_input) {
+		_first_input = t;
+	}
+	
+	if (_video_frames == 0 && _pending_video.empty ()) {
+		/* No video yet; we must postpone these data until we have some */
+		_pending_audio.push_back (AudioRecord (b, t));
+	} else if (!_pending_video.empty() && _pending_audio.empty ()) {
+		/* First audio since we got video */
+		_pending_audio.push_back (AudioRecord (b, t));
+		fix_start ();
+	} else {
+		/* Normal running.  We assume audio time stamps are consecutive */
+		Audio (b);
+		_audio_frames += b->frames ();
+	}
 }
 
 void
@@ -63,38 +115,58 @@ Matcher::process_end ()
 		return;
 	}
 	
-	int64_t audio_short_by_frames = video_frames_to_audio_frames (_video_frames, _sample_rate, _frames_per_second) - _audio_frames;
-
-	_log->log (
-		String::compose (
-			N_("Matching processor has seen %1 video frames (which equals %2 audio frames) and %3 audio frames"),
-			_video_frames,
-			video_frames_to_audio_frames (_video_frames, _sample_rate, _frames_per_second),
-			_audio_frames
-			)
-		);
+	match ((double (_audio_frames) / _sample_rate) - (double (_video_frames) / _frames_per_second));
+}
+
+void
+Matcher::fix_start ()
+{
+	assert (!_pending_video.empty ());
+	assert (!_pending_audio.empty ());
+
+	_log->log (String::compose ("Fixing start; video at %1, audio at %2", _pending_video.front().time, _pending_audio.front().time));
+
+	match (_pending_video.front().time - _pending_audio.front().time);
+
+	for (list<VideoRecord>::iterator i = _pending_video.begin(); i != _pending_video.end(); ++i) {
+		Video (i->image, i->same, i->subtitle);
+	}
+
+	for (list<AudioRecord>::iterator i = _pending_audio.begin(); i != _pending_audio.end(); ++i) {
+		Audio (i->audio);
+	}
 	
-	if (audio_short_by_frames < 0) {
-		
-		_log->log (String::compose (N_("%1 too many audio frames"), -audio_short_by_frames));
-		
-		/* We have seen more audio than video.  Emit enough black video frames so that we reverse this */
-		int const black_video_frames = ceil (-audio_short_by_frames * _frames_per_second / _sample_rate);
+	_pending_video.clear ();
+	_pending_audio.clear ();
+}
+
+void
+Matcher::match (double extra_video_needed)
+{
+	if (extra_video_needed) {
+
+		/* Emit black video frames */
 		
+		int const black_video_frames = ceil (extra_video_needed * _frames_per_second);
+
 		_log->log (String::compose (N_("Emitting %1 frames of black video"), black_video_frames));
 
 		shared_ptr<Image> black (new SimpleImage (_pixel_format.get(), _size.get(), true));
 		black->make_black ();
 		for (int i = 0; i < black_video_frames; ++i) {
 			Video (black, i != 0, shared_ptr<Subtitle>());
+			++_video_frames;
 		}
-		
-		/* Now recompute our check value */
-		audio_short_by_frames = video_frames_to_audio_frames (_video_frames, _sample_rate, _frames_per_second) - _audio_frames;
+
+		extra_video_needed -= black_video_frames / _frames_per_second;
 	}
-	
-	if (audio_short_by_frames > 0) {
-		_log->log (String::compose (N_("Emitted %1 too few audio frames"), audio_short_by_frames));
+
+	if (extra_video_needed < 0) {
+		
+		/* Emit silence */
+		
+		int64_t to_do = rint (-extra_video_needed * _sample_rate);
+		_log->log (String::compose (N_("Emitted %1 frames of silence"), to_do));
 
 		/* Do things in half second blocks as I think there may be limits
 		   to what FFmpeg (and in particular the resampler) can cope with.
@@ -103,7 +175,6 @@ Matcher::process_end ()
 		shared_ptr<AudioBuffers> b (new AudioBuffers (_channels.get(), block));
 		b->make_silent ();
 		
-		int64_t to_do = audio_short_by_frames;
 		while (to_do > 0) {
 			int64_t const this_time = min (to_do, block);
 			b->set_frames (this_time);
@@ -113,3 +184,16 @@ Matcher::process_end ()
 		}
 	}
 }
+
+void
+Matcher::repeat_last_video ()
+{
+	if (!_last_image) {
+		_last_image.reset (new SimpleImage (_pixel_format.get(), _size.get(), true));
+		_last_image->make_black ();
+	}
+
+	Video (_last_image, true, _last_subtitle);
+	++_video_frames;
+}
+