[Gstreamer-bugs] [Bug 111296] New - text overlay plugin

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http://bugzilla.gnome.org/show_bug.cgi?id=111296

Changed by gjc at inescporto.pt.

--- shadow/111296	Mon Apr 21 16:32:00 2003
+++ shadow/111296.tmp.5887	Mon Apr 21 16:32:00 2003
@@ -0,0 +1,59 @@
+Bug#: 111296
+Product: GStreamer
+Version: 0.6.x CVS
+OS: Linux
+OS Details: 
+Status: NEW   
+Resolution: 
+Severity: normal
+Priority: Normal
+Component: gst-plugins
+AssignedTo: gstreamer-maint at bugzilla.gnome.org                            
+ReportedBy: gjc at inescporto.pt               
+QAContact: gstreamer-maint at bugzilla.gnome.org
+TargetMilestone: 0.6.x
+URL: 
+Summary: text overlay plugin
+
+I've made a plugin that renders a text string onto a video frame using the
+pango-ft2 engine.
+
+It has a 'text' property consisting on the text string to render.  It still
+has some problems: 1. the black margin around the text is not smoothed; 2.
+I cannot get the position right, possibly because I don't understand YUV
+very well (can someone help me with this?).  TODO: 1. more properties
+(configuring font, position, etc.)
+
+I would like to add subtitles support to gst-player using this plugin. 
+Ronald Bultje sent to the mailing list the following comments:
+
+-----Ronald Bultje's comments----
+The 'pipeline' idea is that this happens within the gstreamer pipeline
+as well. mpegdemux, for example, can separate the subtitle streams.
+There's another plugin (mpeg2subt) that decodes it into timestamped text
+buffers, and the text plugin should read this and blit it onto the video
+buffer. It can use the timestamp on the buffer for timing etc.
+Properties and so on is nice, but it's basically a quick hack that
+requires a lot of information from the application, while the idea of
+gst is to keep apps simple and have plugins do all the work... The
+pipeline then looks like:
+
+filesrc->mpegdemux.video_00->   mpeg2dec-> textoverlay->xvideosink
+                \\\                                     ///
+                 \\\  .subtitle_00->mpeg2subt->///
+                  \\\
+                   \\\.audio_00->mad->osssink
+
+See? In case of a separate subtitle file, you would open that using a
+separate filesrc:
+
+filesrc->subtitleparse->                     \\\
+                                                      \\\
+filesrc->mpegdemux.video_00->mpeg2dec-> textoverlay->xvideosink
+                  \\\
+                   \\\.audio_00->mad->osssink
+
+This is the design proposed some time ago. You still need the
+textoverlay plugin you've designed, don't worry about that, but you
+transfer the text over a GstPad (timestamped) rather than over a
+property.