Move trimming into the encoder; seems to be cleaner.

26 files changed, 155 insertions, 152 deletions

diff --git a/src/lib/ab_transcoder.cc b/src/lib/ab_transcoder.cc
index 0579aa4ff..c40c0916e 100644
--- a/src/lib/ab_transcoder.cc
+++ b/src/lib/ab_transcoder.cc
@@ -57,7 +57,7 @@ ABTranscoder::ABTranscoder (
 
 	_da->Video.connect (bind (&ABTranscoder::process_video, this, _1, _2, _3, 0));
 	_db->Video.connect (bind (&ABTranscoder::process_video, this, _1, _2, _3, 1));
-	_da->Audio.connect (bind (&Encoder::process_audio, e, _1));
+	_da->Audio.connect (bind (&Encoder::process_audio, e, _1, _2));
 }
 
 ABTranscoder::~ABTranscoder ()
diff --git a/src/lib/decoder.cc b/src/lib/decoder.cc
index 617d57ff6..347c5dbbb 100644
--- a/src/lib/decoder.cc
+++ b/src/lib/decoder.cc
@@ -50,15 +50,12 @@ using boost::shared_ptr;
  *  @param minimal true to do the bare minimum of work; just run through the content.  Useful for acquiring
  *  accurate frame counts as quickly as possible.  This generates no video or audio output.
  */
-Decoder::Decoder (boost::shared_ptr<Film> f, boost::shared_ptr<const Options> o, Job* j, bool minimal)
+Decoder::Decoder (boost::shared_ptr<Film> f, boost::shared_ptr<const Options> o, Job* j)
 	: _film (f)
 	, _opt (o)
 	, _job (j)
-	, _minimal (minimal)
-	, _video_frames_in (0)
-	, _video_frames_out (0)
-	, _audio_frames_in (0)
-	, _audio_frames_out (0)
+	, _video_frame (0)
+	, _audio_frame (0)
 	, _delay_line (0)
 	, _delay_in_frames (0)
 {
@@ -94,13 +91,15 @@ Decoder::process_end ()
 
 		/* Ensure that our video and audio emissions are the same length */
 
-		int64_t audio_short_by_frames = video_frames_to_audio_frames (_video_frames_out) - _audio_frames_out;
+		int64_t audio_short_by_frames = video_frames_to_audio_frames (_video_frame, audio_sample_rate(), frames_per_second()) - _audio_frame;
 
 		_film->log()->log (
-			String::compose ("Decoder has emitted %1 video frames (which equals %2 audio frames) and %3 audio frames",
-					 _video_frames_out,
-					 video_frames_to_audio_frames (_video_frames_out),
-					 _audio_frames_out)
+			String::compose (
+				"Decoder has emitted %1 video frames (which equals %2 audio frames) and %3 audio frames",
+				_video_frame,
+				video_frames_to_audio_frames (_video_frame, audio_sample_rate(), frames_per_second()),
+				_audio_frame
+				)
 			);
 
 		if (audio_short_by_frames < 0) {
@@ -116,15 +115,10 @@ Decoder::process_end ()
 			black->make_black ();
 			for (int i = 0; i < black_video_frames; ++i) {
 				emit_video (black, shared_ptr<Subtitle> ());
-
-				/* This is a bit of a hack, but you can sort-of justify it if you squint at it right.
-				   It's important because the encoder will probably use this to name its output frame.
-				*/
-				++_video_frames_in;
 			}
 
 			/* Now recompute our check value */
-			audio_short_by_frames = video_frames_to_audio_frames (_video_frames_out) - _audio_frames_out;
+			audio_short_by_frames = video_frames_to_audio_frames (_video_frame, audio_sample_rate(), frames_per_second()) - _audio_frame;
 		}
 	
 		if (audio_short_by_frames > 0) {
@@ -147,8 +141,8 @@ Decoder::go ()
 	}
 
 	while (pass () == false) {
-		if (_job && _film->dcp_length()) {
-			_job->set_progress (float (_video_frames_out) / _film->dcp_length().get());
+		if (_job) {
+			_job->set_progress (float (_video_frame) / _film->length().get());
 		}
 	}
 
@@ -162,6 +156,7 @@ Decoder::go ()
 void
 Decoder::process_audio (uint8_t* data, int size)
 {
+	/* XXX: could this be removed? */
 	if (size == 0) {
 		return;
 	}
@@ -236,48 +231,7 @@ Decoder::process_audio (uint8_t* data, int size)
 	}
 
 	_delay_line->feed (audio);
-
-	int const in_frames = audio->frames ();
-
-	if (_opt->decode_range) {
-		/* Decode range in audio frames */
-		pair<int64_t, int64_t> required_range (
-			video_frames_to_audio_frames (_opt->decode_range.get().first),
-			video_frames_to_audio_frames (_opt->decode_range.get().second)
-			);
-		
-		/* Range of this block of data */
-		pair<int64_t, int64_t> this_range (
-			_audio_frames_in,
-			_audio_frames_in + audio->frames()
-			);
-
-		if (this_range.second < required_range.first || required_range.second < this_range.first) {
-			/* No part of this audio is within the required range */
-			audio->set_frames (0);
-		} else if (required_range.first >= this_range.first && required_range.first < this_range.second) {
-			/* Trim start */
-			int64_t const shift = required_range.first - this_range.first;
-			audio->move (shift, 0, audio->frames() - shift);
-			audio->set_frames (audio->frames() - shift);
-		} else if (required_range.second >= this_range.first && required_range.second < this_range.second) {
-			/* Trim end */
-			audio->set_frames (required_range.second - this_range.first);
-		}
-	}
-		
-	if (audio->frames()) {
-		emit_audio (audio);
-	}
-
-	_audio_frames_in += in_frames;
-}
-
-void
-Decoder::emit_audio (shared_ptr<AudioBuffers> audio)
-{
-	Audio (audio);
-	_audio_frames_out += audio->frames ();
+	emit_audio (audio);
 }
 
 /** Called by subclasses to tell the world that some video data is ready.
@@ -287,24 +241,6 @@ Decoder::emit_audio (shared_ptr<AudioBuffers> audio)
 void
 Decoder::process_video (AVFrame* frame)
 {
-	if (_minimal) {
-		++_video_frames_in;
-		return;
-	}
-
-	if (_opt->decode_video_skip != 0 && (_video_frames_in % _opt->decode_video_skip) != 0) {
-		++_video_frames_in;
-		return;
-	}
-
-	if (_opt->decode_range) {
-		pair<SourceFrame, SourceFrame> r = _opt->decode_range.get();
-		if (_video_frames_in < r.first || _video_frames_in >= r.second) {
-			++_video_frames_in;
-			return;
-		}
-	}
-
 	shared_ptr<FilterGraph> graph;
 
 	list<shared_ptr<FilterGraph> >::iterator i = _filter_graphs.begin();
@@ -324,12 +260,11 @@ Decoder::process_video (AVFrame* frame)
 
 	for (list<shared_ptr<Image> >::iterator i = images.begin(); i != images.end(); ++i) {
 		shared_ptr<Subtitle> sub;
-		if (_timed_subtitle && _timed_subtitle->displayed_at (double (video_frames_in()) / _film->frames_per_second())) {
+		if (_timed_subtitle && _timed_subtitle->displayed_at (double (video_frame()) / _film->frames_per_second())) {
 			sub = _timed_subtitle->subtitle ();
 		}
 
 		emit_video (*i, sub);
-		++_video_frames_in;
 	}
 }
 
@@ -342,20 +277,27 @@ Decoder::repeat_last_video ()
 	}
 
 	emit_video (_last_image, _last_subtitle);
-	++_video_frames_in;
 }
 
 void
 Decoder::emit_video (shared_ptr<Image> image, shared_ptr<Subtitle> sub)
 {
-	TIMING ("Decoder emits %1", _video_frames_out);
-	Video (image, _video_frames_in, sub);
-	++_video_frames_out;
+	TIMING ("Decoder emits %1", _video_frame);
+	Video (image, _video_frame, sub);
+	++_video_frame;
+
 	_last_image = image;
 	_last_subtitle = sub;
 }
 
 void
+Decoder::emit_audio (shared_ptr<AudioBuffers> audio)
+{
+	Audio (audio, _audio_frame);
+	_audio_frame += audio->frames ();
+}
+
+void
 Decoder::process_subtitle (shared_ptr<TimedSubtitle> s)
 {
 	_timed_subtitle = s;
@@ -366,15 +308,8 @@ Decoder::process_subtitle (shared_ptr<TimedSubtitle> s)
 	}
 }
 
-
 int
 Decoder::bytes_per_audio_sample () const
 {
 	return av_get_bytes_per_sample (audio_sample_format ());
 }
-
-int64_t
-Decoder::video_frames_to_audio_frames (SourceFrame v) const
-{
-	return ((int64_t) v * audio_sample_rate() / frames_per_second());
-}
diff --git a/src/lib/decoder.h b/src/lib/decoder.h
index 2154da8bf..9f47bf425 100644
--- a/src/lib/decoder.h
+++ b/src/lib/decoder.h
@@ -52,7 +52,7 @@ class FilterGraph;
 class Decoder
 {
 public:
-	Decoder (boost::shared_ptr<Film>, boost::shared_ptr<const Options>, Job *, bool);
+	Decoder (boost::shared_ptr<Film>, boost::shared_ptr<const Options>, Job *);
 	virtual ~Decoder ();
 
 	/* Methods to query our input video */
@@ -80,9 +80,8 @@ public:
 	void process_end ();
 	void go ();
 
-	/** @return the number of video frames we got from the source in the last run */
-	SourceFrame video_frames_in () const {
-		return _video_frames_in;
+	SourceFrame video_frame () const {
+		return _video_frame;
 	}
 
 	virtual std::vector<AudioStream> audio_streams () const {
@@ -101,7 +100,7 @@ public:
 	boost::signals2::signal<void (boost::shared_ptr<Image>, SourceFrame, boost::shared_ptr<Subtitle>)> Video;
 
 	/** Emitted when some audio data is ready */
-	boost::signals2::signal<void (boost::shared_ptr<AudioBuffers>)> Audio;
+	boost::signals2::signal<void (boost::shared_ptr<AudioBuffers>, int64_t)> Audio;
 
 protected:
 	
@@ -121,21 +120,12 @@ protected:
 	/** associated Job, or 0 */
 	Job* _job;
 
-	/** true to do the bare minimum of work; just run through the content.  Useful for acquiring
-	 *  accurate frame counts as quickly as possible.  This generates no video or audio output.
-	 */
-	bool _minimal;
-
 private:
 	void emit_video (boost::shared_ptr<Image>, boost::shared_ptr<Subtitle>);
 	void emit_audio (boost::shared_ptr<AudioBuffers>);
 
-	int64_t video_frames_to_audio_frames (SourceFrame v) const;
-	
-	SourceFrame _video_frames_in;
-	SourceFrame _video_frames_out;
-	int64_t _audio_frames_in;
-	int64_t _audio_frames_out;
+	SourceFrame _video_frame;
+	int64_t _audio_frame;
 	
 	std::list<boost::shared_ptr<FilterGraph> > _filter_graphs;
 
diff --git a/src/lib/decoder_factory.cc b/src/lib/decoder_factory.cc
index 287bba0da..d4a91d8d9 100644
--- a/src/lib/decoder_factory.cc
+++ b/src/lib/decoder_factory.cc
@@ -32,17 +32,17 @@ using boost::shared_ptr;
 
 shared_ptr<Decoder>
 decoder_factory (
-	shared_ptr<Film> f, shared_ptr<const Options> o, Job* j, bool minimal = false
+	shared_ptr<Film> f, shared_ptr<const Options> o, Job* j
 	)
 {
 	if (boost::filesystem::is_directory (f->content_path ())) {
 		/* Assume a directory contains TIFFs */
-		return shared_ptr<Decoder> (new TIFFDecoder (f, o, j, minimal));
+		return shared_ptr<Decoder> (new TIFFDecoder (f, o, j));
 	}
 
 	if (f->content_type() == STILL) {
-		return shared_ptr<Decoder> (new ImageMagickDecoder (f, o, j, minimal));
+		return shared_ptr<Decoder> (new ImageMagickDecoder (f, o, j));
 	}
 	
-	return shared_ptr<Decoder> (new FFmpegDecoder (f, o, j, minimal));
+	return shared_ptr<Decoder> (new FFmpegDecoder (f, o, j));
 }
diff --git a/src/lib/decoder_factory.h b/src/lib/decoder_factory.h
index b86c60c70..765b38816 100644
--- a/src/lib/decoder_factory.h
+++ b/src/lib/decoder_factory.h
@@ -28,5 +28,5 @@ class Job;
 class Log;
 
 extern boost::shared_ptr<Decoder> decoder_factory (
-	boost::shared_ptr<Film>, boost::shared_ptr<const Options>, Job *, bool minimal = false
+	boost::shared_ptr<Film>, boost::shared_ptr<const Options>, Job *
 	);
diff --git a/src/lib/encoder.cc b/src/lib/encoder.cc
index bb23c9e59..b322be04c 100644
--- a/src/lib/encoder.cc
+++ b/src/lib/encoder.cc
@@ -23,7 +23,9 @@
 
 #include "encoder.h"
 #include "util.h"
+#include "options.h"
 
+using std::pair;
 using namespace boost;
 
 int const Encoder::_history_size = 25;
@@ -101,3 +103,51 @@ Encoder::frame_skipped ()
 	boost::mutex::scoped_lock lock (_history_mutex);
 	_just_skipped = true;
 }
+
+void
+Encoder::process_video (shared_ptr<const Image> i, SourceFrame f, boost::shared_ptr<Subtitle> s)
+{
+	if (_opt->decode_video_skip != 0 && (f % _opt->decode_video_skip) != 0) {
+		return;
+	}
+
+	if (_opt->video_decode_range) {
+		pair<SourceFrame, SourceFrame> const r = _opt->video_decode_range.get();
+		if (f < r.first || f >= r.second) {
+			return;
+		}
+	}
+
+	do_process_video (i, f, s);
+}
+
+void
+Encoder::process_audio (shared_ptr<const AudioBuffers> data, int64_t f)
+{
+	if (_opt->audio_decode_range) {
+
+		shared_ptr<AudioBuffers> trimmed (new AudioBuffers (*data.get ()));
+		
+		/* Range that we are encoding */
+		pair<int64_t, int64_t> required_range = _opt->audio_decode_range.get();
+		/* Range of this block of data */
+		pair<int64_t, int64_t> this_range (f, f + trimmed->frames());
+
+		if (this_range.second < required_range.first || required_range.second < this_range.first) {
+			/* No part of this audio is within the required range */
+			return;
+		} else if (required_range.first >= this_range.first && required_range.first < this_range.second) {
+			/* Trim start */
+			int64_t const shift = required_range.first - this_range.first;
+			trimmed->move (shift, 0, trimmed->frames() - shift);
+			trimmed->set_frames (trimmed->frames() - shift);
+		} else if (required_range.second >= this_range.first && required_range.second < this_range.second) {
+			/* Trim end */
+			trimmed->set_frames (required_range.second - this_range.first);
+		}
+
+		data = trimmed;
+	}
+
+	do_process_audio (data);
+}
diff --git a/src/lib/encoder.h b/src/lib/encoder.h
index 704b55e46..2d9780b52 100644
--- a/src/lib/encoder.h
+++ b/src/lib/encoder.h
@@ -57,18 +57,15 @@ public:
 	/** Called to indicate that a processing run is about to begin */
 	virtual void process_begin (int64_t audio_channel_layout) = 0;
 
-	/** Called with a frame of video.
+	/** Call with a frame of video.
 	 *  @param i Video frame image.
 	 *  @param f Frame number within the film's source.
 	 *  @param s A subtitle that should be on this frame, or 0.
 	 */
-	virtual void process_video (boost::shared_ptr<const Image> i, SourceFrame f, boost::shared_ptr<Subtitle> s) = 0;
+	void process_video (boost::shared_ptr<const Image> i, SourceFrame f, boost::shared_ptr<Subtitle> s);
 
-	/** Called with some audio data.
-	 *  @param d Array of pointers to floating point sample data for each channel.
-	 *  @param s Number of frames (ie number of samples in each channel)
-	 */
-	virtual void process_audio (boost::shared_ptr<const AudioBuffers>) = 0;
+	/** Call with some audio data */
+	void process_audio (boost::shared_ptr<const AudioBuffers>, int64_t);
 
 	/** Called when a processing run has finished */
 	virtual void process_end () = 0;
@@ -78,6 +75,17 @@ public:
 	SourceFrame last_frame () const;
 
 protected:
+
+	/** Called with a frame of video.
+	 *  @param i Video frame image.
+	 *  @param f Frame number within the film's source.
+	 *  @param s A subtitle that should be on this frame, or 0.
+	 */
+	virtual void do_process_video (boost::shared_ptr<const Image> i, SourceFrame f, boost::shared_ptr<Subtitle> s) = 0;
+	
+	/** Called with some audio data */
+	virtual void do_process_audio (boost::shared_ptr<const AudioBuffers>) = 0;
+	
 	void frame_done (SourceFrame n);
 	void frame_skipped ();
 	
diff --git a/src/lib/examine_content_job.cc b/src/lib/examine_content_job.cc
index d325102a3..4646fe8fc 100644
--- a/src/lib/examine_content_job.cc
+++ b/src/lib/examine_content_job.cc
@@ -66,10 +66,10 @@ ExamineContentJob::run ()
 
 	descend (0.5);
 
-	_decoder = decoder_factory (_film, o, this, true);
+	_decoder = decoder_factory (_film, o, this);
 	_decoder->go ();
 
-	_film->set_length (_decoder->video_frames_in());
+	_film->set_length (_decoder->video_frame());
 
 	_film->log()->log (String::compose ("Video length is %1 frames", _film->length()));
 
diff --git a/src/lib/ffmpeg_decoder.cc b/src/lib/ffmpeg_decoder.cc
index fa6500b9e..a2ca739e2 100644
--- a/src/lib/ffmpeg_decoder.cc
+++ b/src/lib/ffmpeg_decoder.cc
@@ -55,8 +55,8 @@ using std::vector;
 using std::stringstream;
 using boost::shared_ptr;
 
-FFmpegDecoder::FFmpegDecoder (shared_ptr<Film> f, shared_ptr<const Options> o, Job* j, bool minimal)
-	: Decoder (f, o, j, minimal)
+FFmpegDecoder::FFmpegDecoder (shared_ptr<Film> f, shared_ptr<const Options> o, Job* j)
+	: Decoder (f, o, j)
 	, _format_context (0)
 	, _video_stream (-1)
 	, _audio_stream (-1)
@@ -270,7 +270,7 @@ FFmpegDecoder::pass ()
 			}
 
 			/* Where we are in the output, in seconds */
-			double const out_pts_seconds = video_frames_in() / frames_per_second();
+			double const out_pts_seconds = video_frame() / frames_per_second();
 
 			/* Where we are in the source, in seconds */
 			double const source_pts_seconds = av_q2d (_format_context->streams[_packet.stream_index]->time_base)
@@ -292,7 +292,7 @@ FFmpegDecoder::pass ()
 					_film->log()->log (
 						String::compose (
 							"Extra frame inserted at %1s; source frame %2, source PTS %3",
-							out_pts_seconds, video_frames_in(), source_pts_seconds
+							out_pts_seconds, video_frame(), source_pts_seconds
 							)
 						);
 				}
diff --git a/src/lib/ffmpeg_decoder.h b/src/lib/ffmpeg_decoder.h
index fbd9e5255..0265f7478 100644
--- a/src/lib/ffmpeg_decoder.h
+++ b/src/lib/ffmpeg_decoder.h
@@ -52,7 +52,7 @@ class Log;
 class FFmpegDecoder : public Decoder
 {
 public:
-	FFmpegDecoder (boost::shared_ptr<Film>, boost::shared_ptr<const Options>, Job *, bool);
+	FFmpegDecoder (boost::shared_ptr<Film>, boost::shared_ptr<const Options>, Job *);
 	~FFmpegDecoder ();
 
 	/* Methods to query our input video */
diff --git a/src/lib/film.cc b/src/lib/film.cc
index 26edc80b0..b335f8cc3 100644
--- a/src/lib/film.cc
+++ b/src/lib/film.cc
@@ -259,7 +259,12 @@ Film::make_dcp (bool transcode)
 	o->padding = format()->dcp_padding (shared_from_this ());
 	o->ratio = format()->ratio_as_float (shared_from_this ());
 	if (dcp_length ()) {
-		o->decode_range = make_pair (dcp_trim_start(), dcp_trim_start() + dcp_length().get());
+		o->video_decode_range = make_pair (dcp_trim_start(), dcp_trim_start() + dcp_length().get());
+		o->audio_decode_range = make_pair (
+			video_frames_to_audio_frames (o->video_decode_range.get().first, audio_sample_rate(), frames_per_second()),
+			video_frames_to_audio_frames (o->video_decode_range.get().second, audio_sample_rate(), frames_per_second())
+			);
+			
 	}
 	o->decode_subtitles = with_subtitles ();
 	o->decode_video_skip = dcp_frame_rate (frames_per_second()).skip;
@@ -881,7 +886,7 @@ Film::set_content (string c)
 		shared_ptr<Options> o (new Options ("", "", ""));
 		o->out_size = Size (1024, 1024);
 		
-		shared_ptr<Decoder> d = decoder_factory (shared_from_this(), o, 0, 0);
+		shared_ptr<Decoder> d = decoder_factory (shared_from_this(), o, 0);
 		
 		set_size (d->native_size ());
 		set_frames_per_second (d->frames_per_second ());
@@ -1328,3 +1333,4 @@ Film::set_dci_date_today ()
 {
 	_dci_date = boost::gregorian::day_clock::local_day ();
 }
+
diff --git a/src/lib/film.h b/src/lib/film.h
index 06ebba3ce..ee640f33b 100644
--- a/src/lib/film.h
+++ b/src/lib/film.h
@@ -396,7 +396,7 @@ private:
 	std::string thumb_base_for_frame (SourceFrame) const;
 	void signal_changed (Property);
 	void examine_content_finished ();
-	
+
 	/** Complete path to directory containing the film metadata;
 	 *  must not be relative.
 	 */
diff --git a/src/lib/imagemagick_decoder.cc b/src/lib/imagemagick_decoder.cc
index 81349beca..cc2fd9d23 100644
--- a/src/lib/imagemagick_decoder.cc
+++ b/src/lib/imagemagick_decoder.cc
@@ -27,8 +27,8 @@ using namespace std;
 using namespace boost;
 
 ImageMagickDecoder::ImageMagickDecoder (
-	boost::shared_ptr<Film> f, boost::shared_ptr<const Options> o, Job* j, bool minimal)
-	: Decoder (f, o, j, minimal)
+	boost::shared_ptr<Film> f, boost::shared_ptr<const Options> o, Job* j)
+	: Decoder (f, o, j)
 	, _done (false)
 {
 	_magick_image = new Magick::Image (_film->content_path ());
diff --git a/src/lib/imagemagick_decoder.h b/src/lib/imagemagick_decoder.h
index 85bcf4c5b..b7ab9af18 100644
--- a/src/lib/imagemagick_decoder.h
+++ b/src/lib/imagemagick_decoder.h
@@ -26,7 +26,7 @@ namespace Magick {
 class ImageMagickDecoder : public Decoder
 {
 public:
-	ImageMagickDecoder (boost::shared_ptr<Film>, boost::shared_ptr<const Options>, Job *, bool);
+	ImageMagickDecoder (boost::shared_ptr<Film>, boost::shared_ptr<const Options>, Job *);
 
 	float frames_per_second () const {
 		return static_frames_per_second ();
diff --git a/src/lib/imagemagick_encoder.cc b/src/lib/imagemagick_encoder.cc
index e0e2d1cdc..6c70e3749 100644
--- a/src/lib/imagemagick_encoder.cc
+++ b/src/lib/imagemagick_encoder.cc
@@ -50,7 +50,7 @@ ImageMagickEncoder::ImageMagickEncoder (shared_ptr<const Film> f, shared_ptr<con
 }
 
 void
-ImageMagickEncoder::process_video (shared_ptr<const Image> image, SourceFrame frame, shared_ptr<Subtitle> sub)
+ImageMagickEncoder::do_process_video (shared_ptr<const Image> image, SourceFrame frame, shared_ptr<Subtitle> sub)
 {
 	shared_ptr<Image> scaled = image->scale_and_convert_to_rgb (_opt->out_size, _opt->padding, _film->scaler());
 	shared_ptr<Image> compact (new CompactImage (scaled));
diff --git a/src/lib/imagemagick_encoder.h b/src/lib/imagemagick_encoder.h
index 3d8edd25e..9adfbf56b 100644
--- a/src/lib/imagemagick_encoder.h
+++ b/src/lib/imagemagick_encoder.h
@@ -37,7 +37,9 @@ public:
 	ImageMagickEncoder (boost::shared_ptr<const Film> f, boost::shared_ptr<const Options> o);
 
 	void process_begin (int64_t audio_channel_layout) {}
-	void process_video (boost::shared_ptr<const Image>, SourceFrame, boost::shared_ptr<Subtitle>);
-	void process_audio (boost::shared_ptr<const AudioBuffers>) {}
 	void process_end () {}
+
+private:	
+	void do_process_video (boost::shared_ptr<const Image>, SourceFrame, boost::shared_ptr<Subtitle>);
+	void do_process_audio (boost::shared_ptr<const AudioBuffers>) {}
 };
diff --git a/src/lib/j2k_still_encoder.cc b/src/lib/j2k_still_encoder.cc
index aab686417..2d6c457fc 100644
--- a/src/lib/j2k_still_encoder.cc
+++ b/src/lib/j2k_still_encoder.cc
@@ -49,7 +49,7 @@ J2KStillEncoder::J2KStillEncoder (shared_ptr<const Film> f, shared_ptr<const Opt
 }
 
 void
-J2KStillEncoder::process_video (shared_ptr<const Image> yuv, SourceFrame frame, shared_ptr<Subtitle> sub)
+J2KStillEncoder::do_process_video (shared_ptr<const Image> yuv, SourceFrame frame, shared_ptr<Subtitle> sub)
 {
 	pair<string, string> const s = Filter::ffmpeg_strings (_film->filters());
 	DCPVideoFrame* f = new DCPVideoFrame (
diff --git a/src/lib/j2k_still_encoder.h b/src/lib/j2k_still_encoder.h
index 89222ce18..bc324e967 100644
--- a/src/lib/j2k_still_encoder.h
+++ b/src/lib/j2k_still_encoder.h
@@ -37,7 +37,9 @@ public:
 	J2KStillEncoder (boost::shared_ptr<const Film>, boost::shared_ptr<const Options>);
 
 	void process_begin (int64_t audio_channel_layout) {}
-	void process_video (boost::shared_ptr<const Image>, SourceFrame, boost::shared_ptr<Subtitle>);
-	void process_audio (boost::shared_ptr<const AudioBuffers>) {}
 	void process_end () {}
+
+private:
+	void do_process_video (boost::shared_ptr<const Image>, SourceFrame, boost::shared_ptr<Subtitle>);
+	void do_process_audio (boost::shared_ptr<const AudioBuffers>) {}
 };
diff --git a/src/lib/j2k_wav_encoder.cc b/src/lib/j2k_wav_encoder.cc
index 09e877579..6d777babb 100644
--- a/src/lib/j2k_wav_encoder.cc
+++ b/src/lib/j2k_wav_encoder.cc
@@ -106,7 +106,7 @@ J2KWAVEncoder::close_sound_files ()
 }	
 
 void
-J2KWAVEncoder::process_video (shared_ptr<const Image> yuv, SourceFrame frame, shared_ptr<Subtitle> sub)
+J2KWAVEncoder::do_process_video (shared_ptr<const Image> yuv, SourceFrame frame, shared_ptr<Subtitle> sub)
 {
 	boost::mutex::scoped_lock lock (_worker_mutex);
 
@@ -351,7 +351,7 @@ J2KWAVEncoder::process_end ()
 }
 
 void
-J2KWAVEncoder::process_audio (shared_ptr<const AudioBuffers> audio)
+J2KWAVEncoder::do_process_audio (shared_ptr<const AudioBuffers> audio)
 {
 	shared_ptr<AudioBuffers> resampled;
 	
diff --git a/src/lib/j2k_wav_encoder.h b/src/lib/j2k_wav_encoder.h
index 2272d7f49..b494be8e5 100644
--- a/src/lib/j2k_wav_encoder.h
+++ b/src/lib/j2k_wav_encoder.h
@@ -51,12 +51,13 @@ public:
 	~J2KWAVEncoder ();
 
 	void process_begin (int64_t audio_channel_layout);
-	void process_video (boost::shared_ptr<const Image>, SourceFrame, boost::shared_ptr<Subtitle>);
-	void process_audio (boost::shared_ptr<const AudioBuffers>);
 	void process_end ();
 
 private:
 
+	void do_process_video (boost::shared_ptr<const Image>, SourceFrame, boost::shared_ptr<Subtitle>);
+	void do_process_audio (boost::shared_ptr<const AudioBuffers>);
+	
 	void write_audio (boost::shared_ptr<const AudioBuffers> audio);
 	void encoder_thread (ServerDescription *);
 	void close_sound_files ();
diff --git a/src/lib/options.h b/src/lib/options.h
index 68786c730..29b3b71cd 100644
--- a/src/lib/options.h
+++ b/src/lib/options.h
@@ -24,6 +24,7 @@
 #include <string>
 #include <iomanip>
 #include <sstream>
+#include <boost/optional.hpp>
 #include "util.h"
 
 /** @class Options
@@ -98,8 +99,10 @@ public:
 	bool apply_crop;            ///< true to apply cropping
 
 	/** Range of video frames to decode */
-	boost::optional<std::pair<SourceFrame, SourceFrame> > decode_range;
-
+	boost::optional<std::pair<SourceFrame, SourceFrame> > video_decode_range;
+	/** Range of audio frames to decode */
+	boost::optional<std::pair<int64_t, int64_t> > audio_decode_range;
+	
 	/** Skip frames such that we don't decode any frame where (index % decode_video_skip) != 0; e.g.
 	 *  1 for every frame, 2 for every other frame, etc.
 	 */
diff --git a/src/lib/tiff_decoder.cc b/src/lib/tiff_decoder.cc
index 2c050def6..7cca511dd 100644
--- a/src/lib/tiff_decoder.cc
+++ b/src/lib/tiff_decoder.cc
@@ -44,11 +44,9 @@ using namespace boost;
 /** @param f Our Film.
  *  @param o Options.
  *  @param j Job that we are associated with, or 0.
- *  @param minimal true to do the bare minimum of work; just run through the content.  Useful for acquiring
- *  accurate frame counts as quickly as possible.  This generates no video or audio output.
  */
-TIFFDecoder::TIFFDecoder (boost::shared_ptr<Film> f, boost::shared_ptr<const Options> o, Job* j, bool minimal)
-	: Decoder (f, o, j, minimal)
+TIFFDecoder::TIFFDecoder (boost::shared_ptr<Film> f, boost::shared_ptr<const Options> o, Job* j)
+	: Decoder (f, o, j)
 {
 	string const dir = _film->content_path ();
 	
diff --git a/src/lib/tiff_decoder.h b/src/lib/tiff_decoder.h
index c02a1d03d..1c33443cf 100644
--- a/src/lib/tiff_decoder.h
+++ b/src/lib/tiff_decoder.h
@@ -42,7 +42,7 @@ class Image;
 class TIFFDecoder : public Decoder
 {
 public:
-	TIFFDecoder (boost::shared_ptr<Film>, boost::shared_ptr<const Options>, Job *, bool);
+	TIFFDecoder (boost::shared_ptr<Film>, boost::shared_ptr<const Options>, Job *);
 
 	/* Methods to query our input video */
 	float frames_per_second () const;
diff --git a/src/lib/transcoder.cc b/src/lib/transcoder.cc
index 9515a4344..66d5606af 100644
--- a/src/lib/transcoder.cc
+++ b/src/lib/transcoder.cc
@@ -47,7 +47,7 @@ Transcoder::Transcoder (shared_ptr<Film> f, shared_ptr<const Options> o, Job* j,
 	assert (_encoder);
 	
 	_decoder->Video.connect (bind (&Encoder::process_video, e, _1, _2, _3));
-	_decoder->Audio.connect (bind (&Encoder::process_audio, e, _1));
+	_decoder->Audio.connect (bind (&Encoder::process_audio, e, _1, _2));
 }
 
 /** Run the decoder, passing its output to the encoder, until the decoder
diff --git a/src/lib/util.cc b/src/lib/util.cc
index 5dd39c0e8..219441865 100644
--- a/src/lib/util.cc
+++ b/src/lib/util.cc
@@ -815,3 +815,9 @@ ensure_ui_thread ()
 {
 	assert (this_thread::get_id() == ui_thread);
 }
+
+int64_t
+video_frames_to_audio_frames (SourceFrame v, float audio_sample_rate, float frames_per_second)
+{
+	return ((int64_t) v * audio_sample_rate / frames_per_second);
+}
diff --git a/src/lib/util.h b/src/lib/util.h
index bb0a70a05..7aa9f25e1 100644
--- a/src/lib/util.h
+++ b/src/lib/util.h
@@ -251,5 +251,7 @@ private:
 	float** _data;
 };
 
+extern int64_t video_frames_to_audio_frames (SourceFrame v, float audio_sample_rate, float frames_per_second);
+
 #endif