Raptor Computing Systems Community Forums (BETA)

Software => Applications and Porting => Topic started by: pocock on June 02, 2020, 03:01:38 pm

Title: gstreamer performance, lessons from ffmpeg efforts?
Post by: pocock on June 02, 2020, 03:01:38 pm

A bounty recently provided fixes for ffmpeg (https://www.bountysource.com/issues/34315232-power8-vsx-vectorization-libswscale-input-c)

Are similar fixes needed for gstreamer or any of its dependencies?

Could lessons from the ffmpeg porting be applied to any other similar multimedia frameworks, for example, gstreamer, the WebRTC media stacks in Firefox and Chrome?

Title: Re: gstreamer performance, lessons from ffmpeg efforts?
Post by: pocock on June 04, 2020, 03:44:50 am

Mozilla's bug tracker lists a range of PPC related issues, including problems with the WebRTC stack and Youtube:
https://bugzilla.mozilla.org/buglist.cgi?quicksearch=ppc

I made a post about the bounties on the gstreamer-devel mailing list, some suggestions about future bounty projects have already appeared:
https://lists.freedesktop.org/archives/gstreamer-devel/2020-June/075144.html

Title: Re: gstreamer performance, lessons from ffmpeg efforts?
Post by: Borley on June 04, 2020, 10:05:20 pm

Could this have had anything to do with why my gif and video work ends up producing rows of vertical artifacts in ffmpeg? It's like the render is there, color-wise, but everything is compressed into these one pixel wide lines.

Title: Re: gstreamer performance, lessons from ffmpeg efforts?
Post by: pocock on June 05, 2020, 02:10:26 am

For anything like the problem you describe, the best thing to do is to open a bug report and give them a sample input file, output file and command line

It is also important to give them output of these commands:

ffmpeg -v

ffmpeg -buildconf

This particular thread was about performance but obviously correct functionality is even more important than speed.

Title: Re: gstreamer performance, lessons from ffmpeg efforts?
Post by: Borley on July 19, 2020, 06:37:00 pm

I opened an issue for it at https://trac.ffmpeg.org/ticket/8802

I can still create grainy, slow-to-encode gifs in the meantime.