[mythtv-users] Intro & question

[Aaron Howard]

(Replying to Ivan and Chad in one go...)

On 7/27/06, Ivan Kowalenko <ivan.kowalenko at gmail.com> wrote:
>
> Welcome to the community!
>

Thanks.  I've been following the dev list for some time as I'm
actually a coder (not done anything with MythTV yet, though...still
thinking about it...) but just joined the user list.

On 7/27/06, Ivan Kowalenko <ivan.kowalenko at gmail.com> wrote:
>
> If you're going with HD, you're going to want to upgrade that.

Then Chad <masterclc at gmail.com> wrote:
>
> I agree with Ivan mostly, but I think you might be able to try it in this order:
> Up the storage, definitely up the storage.  Assuming you are going to
> be driving that projector at it's native res (of 1280x720) with actual
> HD content, you'll definitely want more storage.  I'm at ~750GB and
> eyeballing about another 1TB or so...

Okay...so a couple 300GB drives are in my future.  Looks like Newegg
has some Maxtor 300GB 7200RPM 16MB Cache drives for under ~$97/ea.

Chad also wrote:
> Upgrade the Video to a 5200 or 6200

And at one point Ivan wrote:
> Well, probably a DVI port, not an HDMI port, so it would be the same
> cable. People around here seem to like the GeForce FX 5200. It's
> powerful enough to squeeze out 1080p (with a good enough CPU), so
> it's highly probable that the 5200 should handle your requested 720p.

Looks like Newegg also has a Gigabyte-made FX5200 card for $30.99 and
an ASUS-made 6200 card for $39.99.  Side by side comparison has them
nearly identical (DVI, 128MB, etc.) with the 6200 having a bit higher
clock (500Mhz vs. 333Mhz).  Think it's worth the $9?

Back to Ivan, who wrote:
>
> Actually, if you have *just* a Digital Cable box, not an HD digital
> cable box, and it doesn't have HDMI-out or FireWire-out (if it's not
> an HD box, it probably won't), you're not going to get 480p out of it.
>

Right.  In my original plan (before this HD projector destroyed my
impulse control) I was purchasing a native 480p projector, sticking
with SD 480i for TV/cable and using 480p EDTV for DVDs (and GameCube
now-n-then).  But now I have a native 720p projector on a FedEx truck
about to arrive at my door and I'll likely go ahead and get the HD box
from TWC.

>
> Make sure you shield your cable! It may sound paranoid, but over
> whatever distance you're going, it's possible that you'll get signal
> degredation.
>

Do you mean buy shielded cable or somehow shield it myself as well?

>
> I'm surprised they manage to stay in business with a proprietary
> connection, and no way to convert it to a standardized connection
> (HDMI, Component, etc.)
>

It's actually labeled as a DVI input.  The M1 port on the InFocus
projectors might actually even take a DVI connection directly.  It's
just that it's a bit longer than a standard DVI port, so they have
adaper cables (as do 3rd parties) for connecting HDMI and even some
other options to it.

>
> Actually, that isn't *always* true, from what I've heard. Probably
> worth investigating, though.
>

And Chad wrote...
> Yeah, probably a good way to do it.  You may find that your projector
> will scale *any* res you send it, so sending it the native res is
> probably the best to keep scaling minimized (scale once not 8 times).
> So scaling it at the Video cards output res is probably the best
> option, though some may have other ideas.  MythDVD (assuming you use
> mplayer and not xine, the internal player, vlc or whatever other DVD
> player might be used) should be scaling to full screen, so yeah,
> scaling is done before your projector gets it in that case as well.

The projector apparently has a setting for leaving whatever input
signal you send it in its native format (no scaling/stretching, etc.)
If it can fit the image in 1280x720 it will center it, if it can't fit
the image, the projector crops it.  That's largely why I figure if I
can set the video card to 1280x720 and let Linux/the video
driver/MythTV handle scaling the projector can just display it "pass
through" (that's how the manual describes it).

Back to Ivan again...
> Time for a quick lesson in HD: [snip lesson]
> Quick Lesson in Cable and HD: [more snippage]
>

You know, now that you mention it, I knew this already.  I had
forgotten about the DTV standards and how the encoding was done and
such but I did know it.

For the record, I called TW Cable and asked what model I would get if
I upgraded to the HD box.  It's an SA8300HD.  I checked on this and it
apparently does have firewire at least on some models, so I should be
able to get one with it.  But I couldn't find any info on whether it
would work with MythTV or not.  Seems people are having success with
the SA3250 line, however.  Maybe this one will work.  I'm planning on
calling WOW cable tomorrow to see what model box they use for HD
digital subscribers.  I'm not above switching.

And back to Chad's comments...
> So the signal sent by your cable provider may or
> may not be encrypted, it's not decrypted/encoded by the card, so it's
> up to your provider on how they play the game.  Also, in my
> experience, QAM is not as easy to get working as OTA is.  Using an
> external antenna (rabbit ears work for some people, I was fortunate
> enough to have a rooftop antenna in my attic that works great) you can
> get a lot of HD programming that is unencrypted just floating around
> in the air.  You won't get HBO-HD though, but this is really not an
> option for most people anyway since even the firewire will encrypted
> HBO-HD, and the only way to get it is to downgrade it's signal into
> something like a PVR-500's input (max capture is 720x480).

Yeah, I'd like to be able to use MythTV to record from HBO-HD.  HBO is
one of the only reasons I even have cable in the first place.  One of
the things I liked about the pcHDTV card is its support for QAM.  It
seemed to me that QAM support meant I could plug my coax line from TWC
directly into the pcHDTV card and it could decode the OTA stations
(because they're not encrypted) directly.  They're coming down the
wire already...it's just that I don't currently have any equipment
capable of decoding the signal...and it's either get the ATSC signal
OTA for local HD broadcasts and ignore the cable HD channels, or try
to get a cable box w/ Firewire to get the HD signal off the cable box,
excepting any 5C encrypted channels...which would likely be all of the
ones except the OTA channels anyway.  So no ability to record (or even
watch through a MythTV box) HBO-HD shows or ESPN-HD,etc.

I'd really, really like to avoid having multiple inputs into the
projector or having to use a switch box of some kind.

> I actually don't think the GF3 works with the
> Linux Nvidia drivers to output XvMC but I could be dead wrong.

I'm not 100% sure, but I think you are.  I have MythTV running on my
machine with XvMC enabled.  It may have silently just ignored that,
but it didn't hiccup or anything and appears to be working.

> I don't think you'll find and HDMI output on a decently priced
> videocard; if any.  HDMI (my understanding anyway) is basically
> Digital Coax and DVI in 1 small cable.  In this case, a videocard does
> have DVI out and can be combined with a DVI-HDMI dongle.
>

That's my understanding as well (HDMI = DVI + Digital audio).  I'd
like to just use the DVI port off the video card into the projector
and use Firewire to communicate between the MythTV box and the cable
box.

I must say in dealing with this, it is apparent how difficult cable
companies, et. al., make it to DIY and I am sorely tempted to just
pony up the $6.95/mo extra to get their HD DVR solution...that plan I
think has a high WAF but it iritates me to no end.

>
> Good Luck, the MythTV mailing list is archived on Gossamer Threads,
> they are searchable and make for a great reference:
> http://www.gossamer-threads.com/lists/mythtv/

Yeah. I've been searching them a lot.

One last question for anybody still reading this:

I can actually use an RS-232 connection directly to the projector to
control it from the MythTV box, and hopefully will be able to use
firewire to control the cable box, so I just need a remote to control
MythTV and can write scripts or whatever is needed to let it control
everything else when I push button A, etc...but does anybody know of
an RF remote solution that works with MythTV?  I've read plenty about
lirc and IR remotes and whatnot but since my dream setup has a MythTV
box (combined back-end+front-end) in a separate "media room" off to
the side of the home theater, an RF remote solution would be awesome.

Thanks again for the great input!

-Aaron