how to turn my computer into a TV

VDR User user.vdr at gmail.com
Mon Jun 18 15:59:43 UTC 2012


On Sun, Jun 17, 2012 at 6:31 PM, Dieter BSD <dieterbsd at engineer.com> wrote:
> [ Added multimedia@ as that is a more appropriate list than hackers ]
>
>> I just moved into a very cramped apartment
>> we are using a broadcast signal only [current US {NYC} standards]
>
> Recording ATSC takes very little CPU.  Recording NTSC takes either
> a lot of CPU or hardware compression.  Decoding either takes a lot of CPU
> (or hardware decoding which AFAIK FreeBSD doesn't have). You can use
> at(1) for automated recordings.  A full ATSC channel is 19.3 Mbps.
> Some tuners allow filtering by PID, which saves disk space.

Recording doesn't require any compression unless you are transcoding
in real-time. There's no difference between recording ATSC, NTSC, PAL,
etc, and it's actually irrelevant what the stream is. The broadcast
streams are digital so when you "record" them, you are actually just
saving the stream to some type of media (usually a harddrive). It's
like saving a file where the file contents is audio/video, and it
takes however long your show/timer/etc is. The only impact on the cpu
is the same impact you have when you save any big file -- very little
on any modern cpu.

Lastly, it's possible to save a single channel or the entire stream
which usually contains several channels. Even when saving the full
stream, it likely uses far less bandwidth than your media offers so
there's no problem there.


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