codeblog code is freedom — patching my itch

July 13, 2008

zooming in Xine

Filed under: Blogging,Multimedia,Ubuntu — kees @ 11:34 pm

I use Xine to watch DVDs. In the past I’ve encountered “full screen” (4:3) DVDs that carried a wide-screen (16:9) image. This means there were black bars on the top and bottom of the video frame. When watching this sort of video on a 16:9 monitor, you end up with a full border of black surrounding the image. I have encountered this much more frequently when recording standard definition TV that contains wide-screen video. For example, many music videos on MTV have a wide aspect, but are displayed with top/bottom bars in the 4:3 standard definition frame:

16:9 displayed in 4:3 with black top/bottom bars

Displayed on a 16:9 monitor, in Xine:

16:9 within 4:3 on a 16:9 display resulting in black border

In MythTV, there is a “zoom” function that zooms the video, matching the width of the frame to the width of the display. This ends up cropping the top and bottom black bars, allowing the zoom to fit to the width of the frame:

zoomed to 16:9, cropping unneeded 4:3 bars

I have been unable to find such a feature in either Xine or MPlayer. A weekend ago I ran into another DVD doing the wide-screen-in-4:3 trick, and wrote a patch to Xine to create a zoom post-processing filter. Now I can start Xine like this:

xine --disable-post --post zoom path/to/video

And Ctrl-Alt-Shift-P will let me enable-disable post processing. In my case, I’ll be mapping the VPProcessEnable to the same lirc button I use for zooming in MythTV.

© 2008 – 2015, Kees Cook. This work is licensed under a Creative Commons Attribution-ShareAlike 3.0 License.
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