[mythtv-users] Varying data formats during digital reception

HP-mini blm-ubunet at slingshot.co.nz
Mon Nov 5 18:46:32 UTC 2012

> (ii) For digital reception, the tuner does exactly that, it tunes to the 
> multiplex and either pulls a stream out or passes the whole mux forward, ie 
> there is /no/ encoding. Whatever is received gets dumped to disk as is.
> The problem is that the broadcaster may vary the bitrate, resolution, framerate 
> etc of the transmission at any time. Within the contents of a Transport Stream 
> (TS) this is perfectly valid: any TV just decodes what it gets from moment to 
> moment and throws it onto the screen.
> "I am not sure if you loaded these recordings yourself or there is some issue 
> with the database but no matter what Lossless Cut needs to find the type "32" 
> recordedmarkup record and a valid FPS number. Typically the recordedmarkup 
> records are created by MythTV as soon as the recording starts. Lossless cut uses 
> the chanid, starttime and type=32 as the keys to find the correct record."

> The question is: What changes are being made to mythtv to cope with the fact 
> that the bitrate, framerate, resolution, etc of any recorded file may change 
> from instant to instant?
There can be multiple MARK_VIDEO_RATE = "32" entries in recordedmarkup
table. Each entry contains the new/now framerate. The recording process
should be updating this as it builds the recordedseek table.

AFAIK the ffmpeg decoder has to be closed/reopened for all resolution (&
framerate?) changes.

So as you stated..any changes in framerate, resolution has a big impact.

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