Don't bother decoding video frames when we're seeking around trying to find subtitles.

16 files changed, 37 insertions, 27 deletions

diff --git a/src/lib/audio_decoder.cc b/src/lib/audio_decoder.cc
index 22376e3e3..f6133947a 100644
--- a/src/lib/audio_decoder.cc
+++ b/src/lib/audio_decoder.cc
@@ -80,10 +80,10 @@ AudioDecoder::get_audio (AudioFrame frame, AudioFrame length, bool accurate)
 	 */
 	if (accurate) {
 		/* Keep stuffing data into _decoded_audio until we have enough data, or the subclass does not want to give us any more */
-		while ((_decoded_audio.frame > frame || (_decoded_audio.frame + _decoded_audio.audio->frames()) < end) && !pass ()) {}
+		while ((_decoded_audio.frame > frame || (_decoded_audio.frame + _decoded_audio.audio->frames()) < end) && !pass (PASS_REASON_AUDIO)) {}
 		decoded_offset = frame - _decoded_audio.frame;
 	} else {
-		while (_decoded_audio.audio->frames() < length && !pass ()) {}
+		while (_decoded_audio.audio->frames() < length && !pass (PASS_REASON_AUDIO)) {}
 		/* Use decoded_offset of 0, as we don't really care what frames we return */
 	}
 
diff --git a/src/lib/dcp_decoder.cc b/src/lib/dcp_decoder.cc
index ab0df8a86..3bfbd7720 100644
--- a/src/lib/dcp_decoder.cc
+++ b/src/lib/dcp_decoder.cc
@@ -55,7 +55,7 @@ DCPDecoder::DCPDecoder (shared_ptr<const DCPContent> c)
 }
 
 bool
-DCPDecoder::pass ()
+DCPDecoder::pass (PassReason)
 {
 	if (_reel == _reels.end () || !_dcp_content->can_be_played ()) {
 		return true;
diff --git a/src/lib/dcp_decoder.h b/src/lib/dcp_decoder.h
index 20ca2bb67..3a05325c7 100644
--- a/src/lib/dcp_decoder.h
+++ b/src/lib/dcp_decoder.h
@@ -38,8 +38,9 @@ public:
 	DCPDecoder (boost::shared_ptr<const DCPContent>);
 
 private:
+	bool pass (PassReason);
 	void seek (ContentTime t, bool accurate);
-	bool pass ();
+	
 	std::list<ContentTimePeriod> image_subtitles_during (ContentTimePeriod, bool starting) const;
 	std::list<ContentTimePeriod> text_subtitles_during (ContentTimePeriod, bool starting) const;
 
diff --git a/src/lib/dcp_subtitle_decoder.cc b/src/lib/dcp_subtitle_decoder.cc
index 236e99996..93a122590 100644
--- a/src/lib/dcp_subtitle_decoder.cc
+++ b/src/lib/dcp_subtitle_decoder.cc
@@ -46,7 +46,7 @@ DCPSubtitleDecoder::seek (ContentTime time, bool accurate)
 }
 
 bool
-DCPSubtitleDecoder::pass ()
+DCPSubtitleDecoder::pass (PassReason)
 {
 	if (_next == _subtitles.end ()) {
 		return true;
diff --git a/src/lib/dcp_subtitle_decoder.h b/src/lib/dcp_subtitle_decoder.h
index 9a16fb7c8..52e400416 100644
--- a/src/lib/dcp_subtitle_decoder.h
+++ b/src/lib/dcp_subtitle_decoder.h
@@ -28,8 +28,8 @@ public:
 	DCPSubtitleDecoder (boost::shared_ptr<const DCPSubtitleContent>);
 
 protected:
+	bool pass (PassReason);
 	void seek (ContentTime time, bool accurate);
-	bool pass ();
 
 private:
 	std::list<ContentTimePeriod> image_subtitles_during (ContentTimePeriod, bool starting) const;
diff --git a/src/lib/decoder.h b/src/lib/decoder.h
index c1b859865..0703a5426 100644
--- a/src/lib/decoder.h
+++ b/src/lib/decoder.h
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2012-2013 Carl Hetherington <cth@carlh.net>
+    Copyright (C) 2012-2015 Carl Hetherington <cth@carlh.net>
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -41,6 +41,7 @@ public:
 	virtual ~Decoder () {}
 
 protected:	
+
 	/** Seek so that the next pass() will yield the next thing
 	 *  (video/sound frame, subtitle etc.) at or after the requested
 	 *  time.  Pass accurate = true to try harder to ensure that, at worst,
@@ -50,7 +51,14 @@ protected:
 	 *  it may seek to just the right spot.
 	 */
 	virtual void seek (ContentTime time, bool accurate) = 0;
-	virtual bool pass () = 0;
+
+	enum PassReason {
+		PASS_REASON_VIDEO,
+		PASS_REASON_AUDIO,
+		PASS_REASON_SUBTITLE
+	};
+	
+	virtual bool pass (PassReason reason) = 0;
 };
 
 #endif
diff --git a/src/lib/ffmpeg_decoder.cc b/src/lib/ffmpeg_decoder.cc
index a3d647cde..6122a547e 100644
--- a/src/lib/ffmpeg_decoder.cc
+++ b/src/lib/ffmpeg_decoder.cc
@@ -132,7 +132,7 @@ FFmpegDecoder::flush ()
 }
 
 bool
-FFmpegDecoder::pass ()
+FFmpegDecoder::pass (PassReason reason)
 {
 	int r = av_read_frame (_format_context, &_packet);
 
@@ -153,12 +153,13 @@ FFmpegDecoder::pass ()
 	}
 
 	int const si = _packet.stream_index;
+	shared_ptr<const FFmpegContent> fc = _ffmpeg_content;
 
-	if (si == _video_stream && !_ignore_video) {
+	if (si == _video_stream && !_ignore_video && reason != PASS_REASON_SUBTITLE) {
 		decode_video_packet ();
-	} else if (_ffmpeg_content->audio_stream() && _ffmpeg_content->audio_stream()->uses_index (_format_context, si)) {
+	} else if (fc->audio_stream() && fc->audio_stream()->uses_index (_format_context, si) && reason != PASS_REASON_SUBTITLE) {
 		decode_audio_packet ();
-	} else if (_ffmpeg_content->subtitle_stream() && _ffmpeg_content->subtitle_stream()->uses_index (_format_context, si)) {
+	} else if (fc->subtitle_stream() && fc->subtitle_stream()->uses_index (_format_context, si)) {
 		decode_subtitle_packet ();
 	}
 
diff --git a/src/lib/ffmpeg_decoder.h b/src/lib/ffmpeg_decoder.h
index 0a0eea18a..616fa88dd 100644
--- a/src/lib/ffmpeg_decoder.h
+++ b/src/lib/ffmpeg_decoder.h
@@ -53,8 +53,8 @@ public:
 private:
 	friend struct ::ffmpeg_pts_offset_test;
 
+	bool pass (PassReason reason);
 	void seek (ContentTime time, bool);
-	bool pass ();
 	void flush ();
 
 	AVSampleFormat audio_sample_format () const;
diff --git a/src/lib/image_decoder.cc b/src/lib/image_decoder.cc
index 78201fc23..250c8f845 100644
--- a/src/lib/image_decoder.cc
+++ b/src/lib/image_decoder.cc
@@ -43,7 +43,7 @@ ImageDecoder::ImageDecoder (shared_ptr<const ImageContent> c)
 }
 
 bool
-ImageDecoder::pass ()
+ImageDecoder::pass (PassReason)
 {
 	if (_video_position >= _image_content->video_length().frames (_image_content->video_frame_rate ())) {
 		return true;
diff --git a/src/lib/image_decoder.h b/src/lib/image_decoder.h
index 242f69477..ec90051da 100644
--- a/src/lib/image_decoder.h
+++ b/src/lib/image_decoder.h
@@ -34,10 +34,9 @@ public:
 		return _image_content;
 	}
 
-	void seek (ContentTime, bool);
-
 private:
-	bool pass ();
+	bool pass (PassReason);
+	void seek (ContentTime, bool);
 	
 	boost::shared_ptr<const ImageContent> _image_content;
 	boost::shared_ptr<ImageProxy> _image;
diff --git a/src/lib/sndfile_decoder.cc b/src/lib/sndfile_decoder.cc
index 602014d58..09059a8b0 100644
--- a/src/lib/sndfile_decoder.cc
+++ b/src/lib/sndfile_decoder.cc
@@ -65,7 +65,7 @@ SndfileDecoder::~SndfileDecoder ()
 }
 
 bool
-SndfileDecoder::pass ()
+SndfileDecoder::pass (PassReason)
 {
 	if (_remaining == 0) {
 		return true;
diff --git a/src/lib/sndfile_decoder.h b/src/lib/sndfile_decoder.h
index 5ebe1da7b..68c8633a0 100644
--- a/src/lib/sndfile_decoder.h
+++ b/src/lib/sndfile_decoder.h
@@ -30,14 +30,13 @@ public:
 	SndfileDecoder (boost::shared_ptr<const SndfileContent> c);
 	~SndfileDecoder ();
 
-	void seek (ContentTime, bool);
-
 	int audio_channels () const;
 	ContentTime audio_length () const;
 	int audio_frame_rate () const;
 
 private:
-	bool pass ();
+	bool pass (PassReason);
+	void seek (ContentTime, bool);
 	
 	boost::shared_ptr<const SndfileContent> _sndfile_content;
 	SNDFILE* _sndfile;
diff --git a/src/lib/subrip_decoder.cc b/src/lib/subrip_decoder.cc
index bef48ba78..6ed2e5254 100644
--- a/src/lib/subrip_decoder.cc
+++ b/src/lib/subrip_decoder.cc
@@ -48,7 +48,7 @@ SubRipDecoder::seek (ContentTime time, bool accurate)
 }
 
 bool
-SubRipDecoder::pass ()
+SubRipDecoder::pass (PassReason)
 {
 	if (_next >= _subtitles.size ()) {
 		return true;
diff --git a/src/lib/subrip_decoder.h b/src/lib/subrip_decoder.h
index 876f763d3..264ca8899 100644
--- a/src/lib/subrip_decoder.h
+++ b/src/lib/subrip_decoder.h
@@ -32,7 +32,7 @@ public:
 
 protected:
 	void seek (ContentTime time, bool accurate);
-	bool pass ();
+	bool pass (PassReason);
 
 private:
 	std::list<ContentTimePeriod> image_subtitles_during (ContentTimePeriod, bool starting) const;
diff --git a/src/lib/subtitle_decoder.cc b/src/lib/subtitle_decoder.cc
index ac9a67e33..edb291ab8 100644
--- a/src/lib/subtitle_decoder.cc
+++ b/src/lib/subtitle_decoder.cc
@@ -70,7 +70,7 @@ SubtitleDecoder::get (list<T> const & subs, list<ContentTimePeriod> const & sp,
 	 *  (a) give us what we want, or
 	 *  (b) hit the end of the decoder.
 	 */
-	while (!pass() && (subs.empty() || (subs.back().period().to < sp.back().to))) {}
+	while (!pass(PASS_REASON_SUBTITLE) && (subs.empty() || (subs.back().period().to < sp.back().to))) {}
 
 	/* Now look for what we wanted in the data we have collected */
 	/* XXX: inefficient */
@@ -82,6 +82,8 @@ SubtitleDecoder::get (list<T> const & subs, list<ContentTimePeriod> const & sp,
 		}
 	}
 
+	/* XXX: should clear out _decoded_* at some point */
+
 	return out;
 }
 
diff --git a/src/lib/video_decoder.cc b/src/lib/video_decoder.cc
index b7cf1641b..31dc3cdc2 100644
--- a/src/lib/video_decoder.cc
+++ b/src/lib/video_decoder.cc
@@ -96,7 +96,7 @@ VideoDecoder::get_video (VideoFrame frame, bool accurate)
 				break;
 			}
 
-			if (pass ()) {
+			if (pass (PASS_REASON_VIDEO)) {
 				/* The decoder has nothing more for us */
 				break;
 			}
@@ -113,7 +113,7 @@ VideoDecoder::get_video (VideoFrame frame, bool accurate)
 		dec = decoded_video (frame);
 	} else {
 		/* Any frame will do: use the first one that comes out of pass() */
-		while (_decoded_video.empty() && !pass ()) {}
+		while (_decoded_video.empty() && !pass (PASS_REASON_VIDEO)) {}
 		if (!_decoded_video.empty ()) {
 			dec.push_back (_decoded_video.front ());
 		}
@@ -237,7 +237,7 @@ VideoDecoder::video (shared_ptr<const ImageProxy> image, VideoFrame frame)
 	if (_ignore_video) {
 		return;
 	}
-	
+
 	/* We may receive the same frame index twice for 3D, and we need to know
 	   when that happens.
 	*/