[gst-devel] Re: [gst-cvs] dschleef gst-plugins: gst-plugins/ext/pango/

David Schleef ds at schleef.org
Wed Jul 2 15:02:05 CEST 2003

On Wed, Jul 02, 2003 at 01:11:02PM +0200, Ronald Bultje wrote:
> Hey Dave,
> On Wed, 2003-07-02 at 10:07, David Schleef wrote:
> > overlays text of the current timestamp
> Cool! But one small comment, though. ;). I'd prefer if this consisted of
> two plugins, one that overlays random text on the image, and one text
> input plugin.

Heh.  And they both use pango.  Silly me.  The timeoverlay element
was mainly intended to be a proof of concent for using pango, but
I see that has already been done. :)

I'm not entirely sure that having an element that extracts a timestamp
and turns it into a text stream is a better solution than an element
that just overlays the timestamp of the buffer onto the video.  Making
elements as general as possible is nice, but in this case, it pushes
a lot of unnecessary programming (connecting elements and such) up
the next level.

It might be a good idea to create a base class for text overlay, but
timeoverlay is exactly 104 lines more code than the videofilter
template (eveything up to the definition of plugin_desc).  It
seems silly.  Even with a text overlay base class, it would
probably take 104 lines.  (Adding parameters to change font, size,
etc., will change this balance, though.)

Timeoverlay does one thing, does it well, and does it in a very small
amount of code.  I like that.

> The text-overlay plugin is basically similar to the
> subtitle overlay plugin, although that one works on I420 frames. We
> could probably combine these into a general textoverlay plugin that
> overlays any text on any type of raw input image, and then create a
> separate time-text-input plugin and move the actual subtitle plugin from
> Thomas over to HEAD CVS, too.

MPEG subtitles, or subtitles from attached files?  The former are
not text.

Followups to bug #116556.


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