Try moving subtitle adjustment for crop into the decoder.

4 files changed, 43 insertions, 55 deletions

diff --git a/src/lib/decoder.cc b/src/lib/decoder.cc
index e4b892ea4..c4759a872 100644
--- a/src/lib/decoder.cc
+++ b/src/lib/decoder.cc
@@ -48,6 +48,7 @@ extern "C" {
 #include "filter.h"
 #include "delay_line.h"
 #include "ffmpeg_compatibility.h"
+#include "subtitle.h"
 
 using namespace std;
 using namespace boost;
@@ -303,6 +304,14 @@ Decoder::process_video (AVFrame* frame, shared_ptr<Subtitle> sub)
 				image->make_black ();
 			}
 
+			if (sub && _opt->apply_crop) {
+				list<shared_ptr<SubtitleImage> > im = sub->images ();
+				for (list<shared_ptr<SubtitleImage> >::iterator i = im.begin(); i != im.end(); ++i) {
+					Position p = (*i)->position ();
+					(*i)->set_position (Position (p.x - _fs->crop.left, p.y - _fs->crop.top));
+				}
+			}
+
 			TIMING ("Decoder emits %1", _video_frame);
 			Video (image, _video_frame, sub);
 			++_video_frame;
diff --git a/src/lib/subtitle.cc b/src/lib/subtitle.cc
index 040a057fc..0ea5a72d5 100644
--- a/src/lib/subtitle.cc
+++ b/src/lib/subtitle.cc
@@ -70,46 +70,27 @@ SubtitleImage::SubtitleImage (AVSubtitleRect const * rect)
 	}
 }
 
-SubtitleTransform
-subtitle_transform (
-	int target_base_width, int target_base_height,
+Rectangle
+transformed_subtitle_area (
 	float target_x_scale, float target_y_scale,
-	Position sub_pos, int sub_width, int sub_height,
+	Rectangle sub_area,
 	shared_ptr<FilmState> fs
 	)
 {
-	SubtitleTransform tx;
+	Rectangle tx;
 
-	/* The area of the original subtitle, in the coordinate space of the source video frame */
-	Rectangle sub_area (sub_pos.x, sub_pos.y + fs->subtitle_offset, sub_width, sub_height);
-
-	/* The cropped area of the source video frame, in the same coordinate space */
-	Rectangle cropped_target_area (
-		fs->crop.left,
-		fs->crop.top,
-		target_base_width - (fs->crop.left + fs->crop.right),
-		target_base_height - (fs->crop.top + fs->crop.bottom)
-		);
-
-	/* Hence the area of the cropped subtitle, in the same coordinate space */
-	Rectangle cropped_sub_area = sub_area.intersection (cropped_target_area);
-
-	/* The crop that should be applied to the subtitle, in its coordinate space */
-	tx.crop.x = cropped_sub_area.x - sub_area.x;
-	tx.crop.y = cropped_sub_area.y - sub_area.y;
-	tx.crop.w = cropped_sub_area.w;
-	tx.crop.h = cropped_sub_area.h;
+	sub_area.y += fs->subtitle_offset;
 
 	/* We will scale the subtitle by the same amount as the video frame, and also by the additional
 	   subtitle_scale
 	*/
-	tx.transformed.w = cropped_sub_area.w * target_x_scale * fs->subtitle_scale;
-	tx.transformed.h = cropped_sub_area.h * target_y_scale * fs->subtitle_scale;
+	tx.w = sub_area.w * target_x_scale * fs->subtitle_scale;
+	tx.h = sub_area.h * target_y_scale * fs->subtitle_scale;
 
 	/* Then we need a corrective translation, consisting of two parts:
 	 *
 	 * 1.  that which is the result of the scaling of the subtitle by target_x_scale and target_y_scale; this will be
-	 *     (sub_area.x - fs->crop_left) * target_x_scale and (sub_area.y - fs->crop_top) * target_y_scale.
+	 *     sub_area.x * target_x_scale and sub_area.y * target_y_scale.
 	 *
 	 * 2.  that to shift the origin of the scale by fs->subtitle_scale to the centre of the subtitle; this will be
 	 *     (width_before_subtitle_scale * (1 - fs->subtitle_scale) / 2) and
@@ -118,8 +99,8 @@ subtitle_transform (
 	 * Combining these two translations gives these expressions.
 	 */
 	
-	tx.transformed.x = target_x_scale * ((sub_area.x - fs->crop.left) + (cropped_sub_area.w * (1 - fs->subtitle_scale) / 2));
-	tx.transformed.y = target_y_scale * ((sub_area.y - fs->crop.top) + (cropped_sub_area.h * (1 - fs->subtitle_scale) / 2));
+	tx.x = target_x_scale * (sub_area.x + (sub_area.w * (1 - fs->subtitle_scale) / 2));
+	tx.y = target_y_scale * (sub_area.y + (sub_area.h * (1 - fs->subtitle_scale) / 2));
 
 	return tx;
 }
diff --git a/src/lib/subtitle.h b/src/lib/subtitle.h
index fcb6bc70c..0b82320a1 100644
--- a/src/lib/subtitle.h
+++ b/src/lib/subtitle.h
@@ -45,17 +45,9 @@ private:
 	std::list<boost::shared_ptr<SubtitleImage> > _images;
 };
 
-struct SubtitleTransform
-{
-public:
-	Rectangle crop;
-	Rectangle transformed;
-};
-
-extern SubtitleTransform subtitle_transform (
-	int target_base_width, int target_base_height,
+extern Rectangle transformed_subtitle_area (
 	float target_x_scale, float target_y_scale,
-	Position sub_pos, int sub_width, int sub_height,
+	Rectangle sub_area,
 	boost::shared_ptr<FilmState> fs
 	);
 
@@ -64,6 +56,10 @@ class SubtitleImage
 public:
 	SubtitleImage (AVSubtitleRect const *);
 
+	void set_position (Position p) {
+		_position = p;
+	}
+
 	Position position () const {
 		return _position;
 	}
diff --git a/src/wx/film_viewer.cc b/src/wx/film_viewer.cc
index 725ba57de..bfeb44cb9 100644
--- a/src/wx/film_viewer.cc
+++ b/src/wx/film_viewer.cc
@@ -50,11 +50,11 @@ public:
 	/** Handle a paint event */
 	void paint_event (wxPaintEvent& ev)
 	{
-		if (!_film) {
+		if (!_film || _film->num_thumbs() == 0) {
 			wxPaintDC dc (this);
 			return;
 		}
-		
+
 		if (_frame_rebuild_needed) {
 			_image.reset (new wxImage (std_to_wx (_film->thumb_file (_index))));
 
@@ -82,7 +82,7 @@ public:
 
 		if (_film->with_subtitles ()) {
 			for (list<SubtitleView>::iterator i = _subtitles.begin(); i != _subtitles.end(); ++i) {
-				dc.DrawBitmap (*i->bitmap, i->transformed_position.x, i->transformed_position.y, true);
+				dc.DrawBitmap (*i->bitmap, i->transformed_area.x, i->transformed_area.y, true);
 			}
 		}
 	}
@@ -178,16 +178,14 @@ private:
 
 		for (list<SubtitleView>::iterator i = _subtitles.begin(); i != _subtitles.end(); ++i) {
 
-			SubtitleTransform tx = subtitle_transform (
-				_image->GetWidth(), _image->GetHeight(),
-				x_scale, y_scale,
-				i->base_position, i->base_image.GetWidth(), i->base_image.GetHeight(),
-				_film->state_copy()
+			i->transformed_area = transformed_subtitle_area (
+				x_scale, y_scale, i->base_area,	_film->state_copy()
 				);
 
-			i->transformed_image = i->base_image.GetSubImage (wxRect (tx.crop.x, tx.crop.y, tx.crop.w, tx.crop.h));
-			i->transformed_image.Rescale (tx.transformed.w, tx.transformed.h, wxIMAGE_QUALITY_HIGH);
-			i->transformed_position = Position (tx.transformed.x, tx.transformed.y);
+			i->transformed_image = i->base_image;
+			i->transformed_image.Rescale (i->transformed_area.w, i->transformed_area.h, wxIMAGE_QUALITY_HIGH);
+			i->transformed_area.x -= _film->crop().left;
+			i->transformed_area.y -= _film->crop().top;
 			i->bitmap.reset (new wxBitmap (i->transformed_image));
 		}
 	}
@@ -204,12 +202,16 @@ private:
 	struct SubtitleView
 	{
 		SubtitleView (Position p, wxString const & i)
-			: base_position (p)
-			, base_image (i)
-		{}
+			: base_image (i)
+		{
+			base_area.x = p.x;
+			base_area.y = p.y;
+			base_area.w = base_image.GetWidth ();
+			base_area.h = base_image.GetHeight ();
+		}
 
-		Position base_position;
-		Position transformed_position;
+		Rectangle base_area;
+		Rectangle transformed_area;
 		wxImage base_image;
 		wxImage transformed_image;
 		shared_ptr<wxBitmap> bitmap;