[mythtv-users] mplayer digital vs. mythtv digital

Brian Wood beww at beww.org
Sat Jul 24 15:09:56 UTC 2010


On Saturday, July 24, 2010 08:59:35 am Michael R. Hines wrote:
> Hi,
> 
> I'm trying to determine why mythtv's digital live TV capture has
> different output than mplayer's live TV capture.
> 
> So, I did the following:
> 
> bash$ scan /usr/share/dvb/atsc/us-NTSC-center-frequencies-8VSB | tee
> .mplayer/channels.conf # found several channels, great
> bash$ mplayer dvb://NJN-1    # this is my local PBS station
> 
> The output of mplayer is fantastic. Nice signal. Smooth audio/video
> playback.
> 
> But when I play it back in mythtv, it's choppy with lots of beeping
> noises in the audio. The output on my external TV tuner is also very
> good, but for some reason, myth just isn't playing it back as "nicely"
> as mplayer.
> 
> Any reason for this? How could I track this problem down?

Remember that Myth is doing a lot more than just playing the file, thus comparing it to mplayer is not comparing apples and 
apples. Among other things, Myth is checking the database for commercial flags, which means the overhead for MySQL et al.

I'm not sure about the audio beeping, but this is the sort of thing that causes most people to recommend you have your OS 
and database on a separate spindle from your video storage. Myth will make more demands on your system than just playing 
the file. Are you running close to the edge of system performance?

Some system details might help track things down.

beww (former Secaucus resident, who has climbed NJN's Lawrenceville tower many times)





More information about the mythtv-users mailing list