Fix alpha blending with with offset; should help with #1155.

7 files changed, 91 insertions, 87 deletions

diff --git a/src/lib/audio_decoder.cc b/src/lib/audio_decoder.cc
index 5df4047db..4bd6535d8 100644
--- a/src/lib/audio_decoder.cc
+++ b/src/lib/audio_decoder.cc
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2012-2017 Carl Hetherington <cth@carlh.net>
+    Copyright (C) 2012-2018 Carl Hetherington <cth@carlh.net>
 
     This file is part of DCP-o-matic.
 
@@ -98,7 +98,8 @@ AudioDecoder::emit (AudioStreamPtr stream, shared_ptr<const AudioBuffers> data,
 		data = ro;
 	}
 
-	_positions[stream] += Data(stream, ContentAudio (data, _positions[stream])).get_value_or(0);
+	Data(stream, ContentAudio (data, _positions[stream]));
+	_positions[stream] += data->frames();
 }
 
 /** @return Time just after the last thing that was emitted from a given stream */
diff --git a/src/lib/audio_decoder.h b/src/lib/audio_decoder.h
index ba1520ef5..69655cceb 100644
--- a/src/lib/audio_decoder.h
+++ b/src/lib/audio_decoder.h
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2012-2017 Carl Hetherington <cth@carlh.net>
+    Copyright (C) 2012-2018 Carl Hetherington <cth@carlh.net>
 
     This file is part of DCP-o-matic.
 
@@ -54,7 +54,7 @@ public:
 	ContentTime stream_position (AudioStreamPtr stream) const;
 
 	/** @return Number of frames of data that were accepted */
-	boost::signals2::signal<Frame (AudioStreamPtr, ContentAudio)> Data;
+	boost::signals2::signal<void (AudioStreamPtr, ContentAudio)> Data;
 
 private:
 	void silence (int milliseconds);
diff --git a/src/lib/image.cc b/src/lib/image.cc
index 33a0077db..b85451fb3 100644
--- a/src/lib/image.cc
+++ b/src/lib/image.cc
@@ -436,40 +436,6 @@ Image::make_transparent ()
 	memset (data()[0], 0, sample_size(0).height * stride()[0]);
 }
 
-template <class T>
-void
-component (
-	int n,
-	Image* base,
-	shared_ptr<const Image> other,
-	shared_ptr<const Image> rgba,
-	int start_base_x, int start_base_y,
-	int start_other_x, int start_other_y
-	)
-{
-	dcp::Size const base_size = base->sample_size(n);
-	dcp::Size const other_size = other->sample_size(n);
-	int const bhf = base->horizontal_factor(n);
-	int const bvf = base->vertical_factor(n);
-	int const ohf = other->horizontal_factor(n);
-	int const ovf = other->vertical_factor(n);
-	for (int by = start_base_y / bvf, oy = start_other_y / ovf, ry = start_other_y; by < base_size.height && oy < other_size.height; ++by, ++oy, ry += ovf) {
-		/* base image */
-		T* bp = ((T*) (base->data()[n] + by * base->stride()[n])) + start_base_x / bhf;
-		/* overlay image */
-		T* op = ((T*) (other->data()[n] + oy * other->stride()[n]));
-		/* original RGBA for alpha channel */
-		uint8_t* rp = rgba->data()[0] + ry * rgba->stride()[0];
-		for (int bx = start_base_x / bhf, ox = start_other_x / ohf; bx < base_size.width && ox < other_size.width; ++bx, ++ox) {
-			float const alpha = float (rp[3]) / 255;
-			*bp = *op * alpha + *bp * (1 - alpha);
-			++bp;
-			++op;
-			rp += 4 * ohf;
-		}
-	}
-}
-
 void
 Image::alpha_blend (shared_ptr<const Image> other, Position<int> position)
 {
@@ -590,18 +556,66 @@ Image::alpha_blend (shared_ptr<const Image> other, Position<int> position)
 	case AV_PIX_FMT_YUV420P:
 	{
 		shared_ptr<Image> yuv = other->convert_pixel_format (dcp::YUV_TO_RGB_REC709, _pixel_format, false, false);
-		component<uint8_t> (0, this, yuv, other, start_tx, start_ty, start_ox, start_oy);
-		component<uint8_t> (1, this, yuv, other, start_tx, start_ty, start_ox, start_oy);
-		component<uint8_t> (2, this, yuv, other, start_tx, start_ty, start_ox, start_oy);
+		dcp::Size const ts = size();
+		dcp::Size const os = yuv->size();
+		for (int ty = start_ty, oy = start_oy; ty < ts.height && oy < os.height; ++ty, ++oy) {
+			int const hty = ty / 2;
+			int const hoy = oy / 2;
+			uint8_t* tY = data()[0] + (ty * stride()[0]) + start_tx;
+			uint8_t* tU = data()[1] + (hty * stride()[1]) + start_tx / 2;
+			uint8_t* tV = data()[2] + (hty * stride()[2]) + start_tx / 2;
+			uint8_t* oY = yuv->data()[0] + (oy * yuv->stride()[0]) + start_ox;
+			uint8_t* oU = yuv->data()[1] + (hoy * yuv->stride()[1]) + start_ox / 2;
+			uint8_t* oV = yuv->data()[2] + (hoy * yuv->stride()[2]) + start_ox / 2;
+			uint8_t* alpha = other->data()[0] + (oy * other->stride()[0]) + start_ox * 4;
+			for (int tx = start_tx, ox = start_ox; tx < ts.width && ox < os.width; ++tx, ++ox) {
+				float const a = float(alpha[3]) / 255;
+				*tY = *oY * a + *tY * (1 - a);
+				*tU = *oU * a + *tU * (1 - a);
+				*tV = *oV * a + *tV * (1 - a);
+				++tY;
+				++oY;
+				if (tx % 2) {
+					++tU;
+					++tV;
+				}
+				if (ox % 2) {
+					++oU;
+					++oV;
+				}
+				alpha += 4;
+			}
+		}
 		break;
 	}
 	case AV_PIX_FMT_YUV420P10:
 	case AV_PIX_FMT_YUV422P10LE:
 	{
 		shared_ptr<Image> yuv = other->convert_pixel_format (dcp::YUV_TO_RGB_REC709, _pixel_format, false, false);
-		component<uint16_t> (0, this, yuv, other, start_tx, start_ty, start_ox, start_oy);
-		component<uint8_t>  (1, this, yuv, other, start_tx, start_ty, start_ox, start_oy);
-		component<uint8_t>  (2, this, yuv, other, start_tx, start_ty, start_ox, start_oy);
+		dcp::Size const ts = size();
+		dcp::Size const os = yuv->size();
+		for (int ty = start_ty, oy = start_oy; ty < ts.height && oy < os.height; ++ty, ++oy) {
+			uint16_t* tY = (uint16_t *) (data()[0] + (ty * stride()[0])) + start_tx;
+			uint8_t* tU = data()[1] + (ty * stride()[1]) + start_tx;
+			uint8_t* tV = data()[2] + (ty * stride()[2]) + start_tx;
+			uint16_t* oY = (uint16_t *) (yuv->data()[0] + (oy * yuv->stride()[0])) + start_ox;
+			uint8_t* oU = yuv->data()[1] + (oy * yuv->stride()[1]) + start_ox;
+			uint8_t* oV = yuv->data()[2] + (oy * yuv->stride()[2]) + start_ox;
+			uint8_t* alpha = other->data()[0] + (oy * other->stride()[0]) + start_ox * 4;
+			for (int tx = start_tx, ox = start_ox; tx < ts.width && ox < os.width; ++tx, ++ox) {
+				float const a = float(alpha[3]) / 255;
+				*tY = *oY * a + *tY * (1 - a);
+				*tU = *oU * a + *tU * (1 - a);
+				*tV = *oV * a + *tV * (1 - a);
+				++tY;
+				++tU;
+				++tV;
+				++oY;
+				++oU;
+				++oV;
+				alpha += 4;
+			}
+		}
 		break;
 	}
 	default:
diff --git a/src/lib/player.cc b/src/lib/player.cc
index 0bc460465..df0b955a8 100644
--- a/src/lib/player.cc
+++ b/src/lib/player.cc
@@ -526,8 +526,14 @@ Player::pass ()
 	optional<DCPTime> earliest_time;
 
 	BOOST_FOREACH (shared_ptr<Piece> i, _pieces) {
-		if (!i->done) {
-			DCPTime const t = content_time_to_dcp (i, i->decoder->position());
+		if (i->done) {
+			continue;
+		}
+
+		DCPTime const t = content_time_to_dcp (i, i->decoder->position());
+		if (t > i->content->end()) {
+			i->done = true;
+		} else {
 			/* Given two choices at the same time, pick the one with a subtitle so we see it before
 			   the video.
 			*/
@@ -638,17 +644,17 @@ Player::subtitles_for_frame (DCPTime time) const
 	return merge (subtitles);
 }
 
-bool
+void
 Player::video (weak_ptr<Piece> wp, ContentVideo video)
 {
 	shared_ptr<Piece> piece = wp.lock ();
 	if (!piece) {
-		return false;
+		return;
 	}
 
 	FrameRateChange frc(piece->content->active_video_frame_rate(), _film->video_frame_rate());
 	if (frc.skip && (video.frame % 2) == 1) {
-		return false;
+		return;
 	}
 
 	/* Time of the first frame we will emit */
@@ -659,7 +665,7 @@ Player::video (weak_ptr<Piece> wp, ContentVideo video)
 		time < piece->content->position() ||
 		time >= piece->content->end() ||
 		(_last_video_time && time < *_last_video_time)) {
-		return false;
+		return;
 	}
 
 	/* Fill gaps that we discover now that we have some video which needs to be emitted */
@@ -697,21 +703,16 @@ Player::video (weak_ptr<Piece> wp, ContentVideo video)
 		emit_video (_last_video[wp], t);
 		t += one_video_frame ();
 	}
-
-	return true;
 }
 
-/** @return Number of input frames that were `accepted'.  This is the number of frames passed in
- *  unless some were discarded at the end of the block.
- */
-Frame
+void
 Player::audio (weak_ptr<Piece> wp, AudioStreamPtr stream, ContentAudio content_audio)
 {
 	DCPOMATIC_ASSERT (content_audio.audio->frames() > 0);
 
 	shared_ptr<Piece> piece = wp.lock ();
 	if (!piece) {
-		return 0;
+		return;
 	}
 
 	shared_ptr<AudioContent> content = piece->content->audio;
@@ -722,33 +723,26 @@ Player::audio (weak_ptr<Piece> wp, AudioStreamPtr stream, ContentAudio content_a
 	/* And the end of this block in the DCP */
 	DCPTime end = time + DCPTime::from_frames(content_audio.audio->frames(), content->resampled_frame_rate());
 
-	/* We consider frames trimmed off the beginning to nevertheless be `accepted'; it's only frames trimmed
-	   off the end that are considered as discarded.  This logic is necessary to ensure correct reel lengths,
-	   although the precise details escape me at the moment.
-	*/
-	Frame accepted = content_audio.audio->frames();
-
 	/* Remove anything that comes before the start or after the end of the content */
 	if (time < piece->content->position()) {
 		pair<shared_ptr<AudioBuffers>, DCPTime> cut = discard_audio (content_audio.audio, time, piece->content->position());
 		if (!cut.first) {
 			/* This audio is entirely discarded */
-			return accepted;
+			return;
 		}
 		content_audio.audio = cut.first;
 		time = cut.second;
 	} else if (time > piece->content->end()) {
 		/* Discard it all */
-		return 0;
+		return;
 	} else if (end > piece->content->end()) {
 		Frame const remaining_frames = DCPTime(piece->content->end() - time).frames_round(_film->audio_frame_rate());
 		if (remaining_frames == 0) {
-			return 0;
+			return;
 		}
 		shared_ptr<AudioBuffers> cut (new AudioBuffers (content_audio.audio->channels(), remaining_frames));
 		cut->copy_from (content_audio.audio.get(), remaining_frames, 0, 0);
 		content_audio.audio = cut;
-		accepted = content_audio.audio->frames();
 	}
 
 	DCPOMATIC_ASSERT (content_audio.audio->frames() > 0);
@@ -776,7 +770,6 @@ Player::audio (weak_ptr<Piece> wp, AudioStreamPtr stream, ContentAudio content_a
 	_audio_merger.push (content_audio.audio, time);
 	DCPOMATIC_ASSERT (_stream_states.find (stream) != _stream_states.end ());
 	_stream_states[stream].last_push_end = time + DCPTime::from_frames (content_audio.audio->frames(), _film->audio_frame_rate());
-	return accepted;
 }
 
 void
diff --git a/src/lib/player.h b/src/lib/player.h
index ed55b6284..9dd5afd26 100644
--- a/src/lib/player.h
+++ b/src/lib/player.h
@@ -105,8 +105,8 @@ private:
 	ContentTime dcp_to_content_time (boost::shared_ptr<const Piece> piece, DCPTime t) const;
 	DCPTime content_time_to_dcp (boost::shared_ptr<const Piece> piece, ContentTime t) const;
 	boost::shared_ptr<PlayerVideo> black_player_video_frame () const;
-	bool video (boost::weak_ptr<Piece>, ContentVideo);
-	Frame audio (boost::weak_ptr<Piece>, AudioStreamPtr, ContentAudio);
+	void video (boost::weak_ptr<Piece>, ContentVideo);
+	void audio (boost::weak_ptr<Piece>, AudioStreamPtr, ContentAudio);
 	void image_subtitle_start (boost::weak_ptr<Piece>, ContentImageSubtitle);
 	void text_subtitle_start (boost::weak_ptr<Piece>, ContentTextSubtitle);
 	void subtitle_stop (boost::weak_ptr<Piece>, ContentTime);
diff --git a/src/lib/video_decoder.cc b/src/lib/video_decoder.cc
index b9ead52c8..3625e074f 100644
--- a/src/lib/video_decoder.cc
+++ b/src/lib/video_decoder.cc
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2012-2016 Carl Hetherington <cth@carlh.net>
+    Copyright (C) 2012-2018 Carl Hetherington <cth@carlh.net>
 
     This file is part of DCP-o-matic.
 
@@ -59,11 +59,9 @@ VideoDecoder::emit (shared_ptr<const ImageProxy> image, Frame frame)
 		return;
 	}
 
-	optional<bool> taken;
-
 	switch (_content->video->frame_type ()) {
 	case VIDEO_FRAME_TYPE_2D:
-		taken = Data (ContentVideo (image, frame, EYES_BOTH, PART_WHOLE));
+		Data (ContentVideo (image, frame, EYES_BOTH, PART_WHOLE));
 		break;
 	case VIDEO_FRAME_TYPE_3D:
 	{
@@ -71,35 +69,33 @@ VideoDecoder::emit (shared_ptr<const ImageProxy> image, Frame frame)
 		   frame this one is.
 		*/
 		bool const same = (_last_emitted && _last_emitted.get() == frame);
-		taken = Data (ContentVideo (image, frame, same ? EYES_RIGHT : EYES_LEFT, PART_WHOLE));
+		Data (ContentVideo (image, frame, same ? EYES_RIGHT : EYES_LEFT, PART_WHOLE));
 		_last_emitted = frame;
 		break;
 	}
 	case VIDEO_FRAME_TYPE_3D_ALTERNATE:
-		taken = Data (ContentVideo (image, frame / 2, (frame % 2) ? EYES_RIGHT : EYES_LEFT, PART_WHOLE));
+		Data (ContentVideo (image, frame / 2, (frame % 2) ? EYES_RIGHT : EYES_LEFT, PART_WHOLE));
 		frame /= 2;
 		break;
 	case VIDEO_FRAME_TYPE_3D_LEFT_RIGHT:
-		taken = Data (ContentVideo (image, frame, EYES_LEFT, PART_LEFT_HALF));
-		taken = Data (ContentVideo (image, frame, EYES_RIGHT, PART_RIGHT_HALF));
+		Data (ContentVideo (image, frame, EYES_LEFT, PART_LEFT_HALF));
+		Data (ContentVideo (image, frame, EYES_RIGHT, PART_RIGHT_HALF));
 		break;
 	case VIDEO_FRAME_TYPE_3D_TOP_BOTTOM:
-		taken = Data (ContentVideo (image, frame, EYES_LEFT, PART_TOP_HALF));
-		taken = Data (ContentVideo (image, frame, EYES_RIGHT, PART_BOTTOM_HALF));
+		Data (ContentVideo (image, frame, EYES_LEFT, PART_TOP_HALF));
+		Data (ContentVideo (image, frame, EYES_RIGHT, PART_BOTTOM_HALF));
 		break;
 	case VIDEO_FRAME_TYPE_3D_LEFT:
-		taken = Data (ContentVideo (image, frame, EYES_LEFT, PART_WHOLE));
+		Data (ContentVideo (image, frame, EYES_LEFT, PART_WHOLE));
 		break;
 	case VIDEO_FRAME_TYPE_3D_RIGHT:
-		taken = Data (ContentVideo (image, frame, EYES_RIGHT, PART_WHOLE));
+		Data (ContentVideo (image, frame, EYES_RIGHT, PART_WHOLE));
 		break;
 	default:
 		DCPOMATIC_ASSERT (false);
 	}
 
-	if (taken.get_value_or(false)) {
-		_position = ContentTime::from_frames (frame, _content->active_video_frame_rate ());
-	}
+	_position = ContentTime::from_frames (frame, _content->active_video_frame_rate ());
 }
 
 void
diff --git a/src/lib/video_decoder.h b/src/lib/video_decoder.h
index c5e2ea4cf..959ff7ac7 100644
--- a/src/lib/video_decoder.h
+++ b/src/lib/video_decoder.h
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2012-2016 Carl Hetherington <cth@carlh.net>
+    Copyright (C) 2012-2018 Carl Hetherington <cth@carlh.net>
 
     This file is part of DCP-o-matic.
 
@@ -60,7 +60,7 @@ public:
 	void emit (boost::shared_ptr<const ImageProxy>, Frame frame);
 
 	/** @return true if the emitted data was accepted, false if not */
-	boost::signals2::signal<bool (ContentVideo)> Data;
+	boost::signals2::signal<void (ContentVideo)> Data;
 
 private:
 	boost::shared_ptr<const Content> _content;