[mythtv-users] 1394

[Andrew Dodd]

Quoting Chris Moseng <mosengch at grinnell.edu>:

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> I've gone back and tried to find a discussion about the relationship
> between 1394 DV and MythTV and I'm still just as confused as when I
> started.
>
> Is the reason that MythTV seems to have a blindspot for 1394 simply
> because nobody has needed to scratch that itch in this community?
>
> I have a Sony DVMC-DA2 that converts analog A/V to firewire, and back
> again. It seems (to someone without the nitty gritty, bit-level
> familiarity of MPEG-2 transport and display) a perfect device to
> digitize digital video for MythTV. As would most 1394 DV devices.
>
> So what exactly would I need to overcome to use this box as an input?
> Would a mere pipe take care of it, or is there something I'm missing
> that makes it clear why this is such a difficult/inappropriate
> technological marriage? It seems a shame to have this nifty little
> breakout box so capable of MPEG-2 encoding, but be unable to use it.
Um, you're not making much sense here...

DV and MPEG-2 are entirely different codecs - DV is essentially high-quality
MJPEG.

Support for DV video is relatively mature under Linux.

Support for MPEG-2 transport streams under Linux is extremely immature.  There's
hardly been any work done on it due to the fact that until recently, HDTV tuners
with MPEG-2 outputs were almost impossible to find.  It won't be long before
those that do have 1394 outputs use 5C encryption.

DV is completely unsuited to PVR functionality due to its insanely high bitrate
- 13 GB/hour or so for 720x480 video.  An analog-to-DV box without a tuner runs
a minimum of $200.  An internal PCI card that records to MPEG-2 can be had for
less than $100.