GNOME Bugzilla – Bug 742817
avvideoscale: Fix element and enable it again
Last modified: 2016-12-27 09:26:39 UTC
On both iOS and OS X versions i get error that element 'avvideoscale' does not exist though libav is enabled.
Per Christian's replay porting of this element is still work in progress.
It's disabled by this commit:
Author: Tim-Philipp Müller <email@example.com>
Date: Thu Jan 17 23:56:17 2013 +0000
Disable libswscale/avvideoscale plugin until it works at least somewhat
It needs some fixing.
Do we really want to re-enable these? Do they provide additional features or better performance?
I think one advantage used to be that you could do conversion+scaling in one go, but videoscale can do that as well now if I'm not mistaken (at least the internal VideoConverter, not sure if it was enabled in the elements).
*** Bug 703712 has been marked as a duplicate of this bug. ***
IMHO no reason, especially not after enabling conversion+scaling in videoconvert/videoscale at once.
I patched avvideoscale and found it significantly faster than videoscale for lanczos(and also other methods). Here is the run time
gst-launch-1.0 filesrc location=/root/images/skyline2.jpg ! decodebin ! imagefreeze ! avvideoscale method=9 ! video/x-raw,width=640,height=360 ! fakesink num-buffers=1000
Execution ended after 0:00:14.8238
gst-launch-1.0 filesrc location=/root/images/skyline2.jpg ! decodebin ! imagefreeze ! videoscale method=3 ! video/x-raw,width=640,height=360 ! fakesink num-buffers=1000
Execution ended after 0:00:37.7101
Visually there is very little difference, though avvideoscale output is mildly sharper
Input image is a 4k image converted to 640x360
Am I missing something?