GNOME Bugzilla – Bug 515240
Draw subtitles after scaling video
Last modified: 2014-12-07 17:56:14 UTC
Please describe the problem: The video subtitles are very pixelized. Steps to reproduce: 1. 2. 3. Actual results: Expected results: Does this happen every time? Yes Other information: This not deppends on font type and neither on its size
Hello, Could you elaborate a little more and add a screenshot of the problem please ?
And tell us which backend you use as well, and a way to reproduce the problem.
This happens at least with the gstreamer backend (I haven't tried with the xine backend). The problem is easy to see if you use a really large subtitle font. Please see attached screenshot.
Created attachment 108071 [details] screenshot of the problem
What's the resolution of the video? Does it happen with another (larger) video? I'm guessing it would be because the subtitles are blended into the video, and then scaled, rather than being added after the scaling (which is usually done by the Xv adapter).
(In reply to comment #5) > What's the resolution of the video? Does it happen with another (larger) video? The resolution of the video where the screenshot is from is 800 x 336. I don't have video with higher resolution at hand. > I'm guessing it would be because the subtitles are blended into the video, and > then scaled, rather than being added after the scaling (which is usually done > by the Xv adapter). Would it be possible to add the subtitles after scaling the video?
(In reply to comment #6) > (In reply to comment #5) > > What's the resolution of the video? Does it happen with another (larger) video? > > The resolution of the video where the screenshot is from is 800 x 336. I don't > have video with higher resolution at hand. There's HD trailers to download on the internet... > > I'm guessing it would be because the subtitles are blended into the video, and > > then scaled, rather than being added after the scaling (which is usually done > > by the Xv adapter). > > Would it be possible to add the subtitles after scaling the video? The hardware does the scaling, so it would need to be done in a completely different way.
(In reply to comment #7) > There's HD trailers to download on the internet... My computer can't manage those. Someone else will have to test that.
Moving that to GStreamer, as Totem doesn't do the subtitle rendering anyway. The drawing of the subtitles is currently done before passing the video to the video sink, in the original size. Instead, the overlay should be drawn after the video has been scaled, but before it is displayed.
*** Bug 622444 has been marked as a duplicate of this bug. ***
I don't open a new bug report, but when viewing a video, and changing aspect ratio of the video, the subtitles (LOADED from an SRT file) also change of aspect ratio which is rather a bad behavior to my point of view. joined screenshots to illustrate
well is it another bug ? when I take screenshot with totem, it does not take into account the aspect ratio I have chosen. So I had to use a screenshot utility to show you what I want... sight
Created attachment 192035 [details] default aspect ratio 2.35:1
Created attachment 192036 [details] aspect ratio 16/9
Created attachment 192037 [details] aspect ratio 4:3
I think textoverlay not taking into account the aspect-ratio is a separate bug in its own right, even if a solution for this bug would probably fix that issue as well.
*** Bug 370733 has been marked as a duplicate of this bug. ***
*** Bug 736001 has been marked as a duplicate of this bug. ***
Will be fixed in GNOME 3.16 with the new clutter-gst support. See bug 731848 for details.