[mythtv-users] Live TV Jitter and CODEC Selection

[Ben Healy]

From: jim <jim_32766 at hotmail.com>
>To: mythtv-users at mythtv.org 
>Sent: Thursday, 26 February 2015, 13:05
>Subject: [mythtv-users] Live TV Jitter and CODEC Selection
> 
>
>Playback of recorded media or streams is smooth. Sometimes live tv is 
>smooth and other times it has an irritating jitter. A little 
>investigation revealed that playback of recorded media always uses VAAPI 
>acceleration ( my system uses an Intel I3 4330 ) and live tv appears to 
>sometimes use ffmpeg instead of VAAPI. The live tv is smooth with VAAPI 
>and has jitter with ffmpeg. I've checked my setup and VAAPI is the only 
>codec selected in Setup->Video->Playback in the Current Video Playback 
>Profile. I added a VAAPI High Quality choice and made VAAPI the only 
>codec option.
>
>Does anyone know why ffmpeg is sometimes used for live tv and, more 
>importantly, how to make VAAPI be the only codec used for live tv?
>
>Thanks,
>
>Jim
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I believe there is a bug with Live TV, where every second channel change VAAPI will be unavailable and will fall back to ffmpeg.

I'm using a Chromebox which is a Haswell celeron 2955u with graphics equivalent to HD4000 and I find that the OpenGL normal profile gives better quality on interlaced content than VAAPI. Perhaps give it a try.

Ben