[mythtv-users] Best Sat receiver for Dish Network
Michael T. Dean
mtdean at thirdcontact.com
Wed Mar 8 22:38:36 UTC 2006
On 03/08/2006 04:35 PM, Brian Wood wrote:
> On Mar 8, 2006, at 2:22 PM, Michael T. Dean wrote:
>> On 03/08/2006 04:17 PM, Brian Wood wrote:
>>> My Dish Network receiver does get several HD channels and outputs them via component analog or HDMI digital, but only on the first channel of a two-channel receiver.
>> But, as today's general-purpose processors struggle to /decode/ HDTV in real-time, there's no way you could /encode/ HDTV in real-time without some specialized equipment using application specific processors.
>>> It can record HD as well, storing up to 24 hours of 1080i content.
>> But, it won't output that HDTV for you to put on your Myth box.
>
> Well I admit I haven't tried connecting any HD into my Myth box yet, but the receiver outputs live or recorded HD as un-encrypted normal component analog or digital HDMI video, which can feed any HD-capable monitor. There is nothing "proprietary" about the signals it outputs. I'm sad to hear this is not the case with DirecTV, sounds like I
> chose the right satellite provider.
Actually, DirecTV will also output component analog or digital DVI/HDMI,
but it does us no good.
Even if you cobbled together an array of BTTV capture cards (and worked
up a driver) to grab that analog output or created your own DVI/HDMI
capture mechanism, you'd be looking at some serious storage
requirements. Uncompressed 16-bit color video at 720x480 (interlaced at
30 frames/sec and 60 fields/sec) takes about 70GiB/hr and 105GiB/hr for
24-bit color. Since we can't encode it in real time, we'd have to store
the uncompressed, then let the CPU crunch for hours to encode each hour
captured.
With ATSC, the storage requirements are much greater:
Format 16-bit Color 24-bit Color
------ ----------- ------------
720p24 148 GiB/hr 222GiB/hr
720p30 185 GiB/hr 278GiB/hr
720p60 371 GiB/hr 556GiB/hr=9.3Gib/min
1080p24 334 GiB/hr 501GiB/hr
1080p30 417 GiB/hr 626GiB/hr=10.4GiB/min
1080i60 (same as 1080p30)
And, on top of that, you'll need to store the audio (which you should be
able to compress in real-time ;).
> I haven't heard of an HD capture card that accepts baseband input,
> but there are some very fast CPUs out there now, and when you think
> about it most of us are using specialized processors to encode SD
> (ie: PVRs), so there's no reason to think that HD equivalents are too
> far in the future.
Yeah--as soon as those guys from the MPAA, etc. say it's OK to release
them (which will happen as soon as they get their broadcast flag,
analog-hole protection, etc.). ;)
So, basically, you won't get HDTV from a satellite box at this time. I
don't expect to see it being possible for quite some time--at least not
in the US.
Mike
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