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#1 problem with HDTV - no DVI/component-in PVR

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Anonymous
October 12, 2004 3:59:21 PM

Archived from groups: alt.tv.tech.hdtv (More info?)

My major frustration with HDTV is this: why hasnt anyone yet designed
an HDPVR
which simply accepts component and/or DVI input????

We've got OTA HD tuner card-based solutions, we've got DirecTivo HD
for satellite tuning, and the cable companies have started launching
their own mediocre cable-tuning HDTV PVRs...someone even has a QUAM
(sp?) card cable HDTV tuner. There are firewire solutions emerging,
but not every tuner has a firewire out...

But I dont understand why no one just simply has a DVI-in or
component-in card for PCs! This is exactly how TiVo took off - nearly
every video system has a composite out S-VIDEO, or can be fitted with
a converter for composite, so Tivo could be hooked up to anything.

Seemingly, no one wants to design the obvious solution - a
DVI/component-in PVR, with an IR blaster and composite/optical audio
in.

Anyone know *why*??
Anonymous
October 12, 2004 5:33:19 PM

Archived from groups: alt.tv.tech.hdtv (More info?)

On 12 Oct 2004 11:59:21 -0700, in article
<53e2ec95.0410121059.5704565c@posting.google.com>,
brundlefly76@hotmail.com (Seth Brundle) wrote:

>We've got OTA HD tuner card-based solutions, we've got DirecTivo HD
>for satellite tuning, and the cable companies have started launching
>their own mediocre cable-tuning HDTV PVRs...someone even has a QUAM
>(sp?) card cable HDTV tuner. There are firewire solutions emerging,
>but not every tuner has a firewire out...
>
>Seemingly, no one wants to design the obvious solution - a
>DVI/component-in PVR, with an IR blaster and composite/optical audio
>in.
>
>Anyone know *why*??

They *are* designing the obvious solution. Your idea isn't it. It's
much more straightforward, cheaper, and higher quality to just store the
incoming already compressed bits from whatever source you are using,
than to take uncompressed HD video & recompress it, which takes
expensive HD MPEG encoding hardware and introduces another generation of
encoding loss. DVI recording would also encounter encryption
difficulties.
--
Stephen Tu
stephtu@surfbest.net
Anonymous
October 12, 2004 9:47:23 PM

Archived from groups: alt.tv.tech.hdtv (More info?)

"Seth Brundle" <brundlefly76@hotmail.com> wrote in message
news:53e2ec95.0410121059.5704565c@posting.google.com...
> My major frustration with HDTV is this: why hasnt anyone yet designed
> an HDPVR
> which simply accepts component and/or DVI input????
>
> We've got OTA HD tuner card-based solutions, we've got DirecTivo HD
> for satellite tuning, and the cable companies have started launching
> their own mediocre cable-tuning HDTV PVRs...someone even has a QUAM
> (sp?) card cable HDTV tuner. There are firewire solutions emerging,
> but not every tuner has a firewire out...
>
> But I dont understand why no one just simply has a DVI-in or
> component-in card for PCs! This is exactly how TiVo took off - nearly
> every video system has a composite out S-VIDEO, or can be fitted with
> a converter for composite, so Tivo could be hooked up to anything.
>
> Seemingly, no one wants to design the obvious solution - a
> DVI/component-in PVR, with an IR blaster and composite/optical audio
> in.
>
> Anyone know *why*??

simple... the component or DVI monitor outs are raw uncompressed HD video
1920x1080x3x30 Bytes per second... data that needs high quality
compression - probably two pass, into MPEG2 or other suitable codec.

and the computing horsepower required to re-compressed this incredibly high
datarate stream is simply too expensive for home use

this will not always be true... but we need a few more Moore's Law doublings
to bring the task down to PC size.
Related resources
Anonymous
October 12, 2004 11:54:59 PM

Archived from groups: alt.tv.tech.hdtv (More info?)

Well, uncompressed HDTV is 1.5Gbps. Mull that one over for a bit. Its not
that nobody wants to design the obvious solution, its that nobody would buy
it because it would cost so much money.

Compressed HDTV as we know it is around 12-19mbps, a much more reasonable
rate to capture and save for later. That's what the tuner cards and Tivo
units do. They have to capture the transport stream prior to it being blown
up to usable data. To compress 1.5Gbps to 19mbps on the fly, in real time,
is not as simple as we might like to think. To store it uncompressed would
require HUGE amounts of disk space.

I have gone over this quite a bit, if you have any more questions just ask.

--Dan

"Seth Brundle" <brundlefly76@hotmail.com> wrote in message
news:53e2ec95.0410121059.5704565c@posting.google.com...
> My major frustration with HDTV is this: why hasnt anyone yet designed
> an HDPVR
> which simply accepts component and/or DVI input????
>
> We've got OTA HD tuner card-based solutions, we've got DirecTivo HD
> for satellite tuning, and the cable companies have started launching
> their own mediocre cable-tuning HDTV PVRs...someone even has a QUAM
> (sp?) card cable HDTV tuner. There are firewire solutions emerging,
> but not every tuner has a firewire out...
>
> But I dont understand why no one just simply has a DVI-in or
> component-in card for PCs! This is exactly how TiVo took off - nearly
> every video system has a composite out S-VIDEO, or can be fitted with
> a converter for composite, so Tivo could be hooked up to anything.
>
> Seemingly, no one wants to design the obvious solution - a
> DVI/component-in PVR, with an IR blaster and composite/optical audio
> in.
>
> Anyone know *why*??
Anonymous
October 13, 2004 12:06:10 AM

Archived from groups: alt.tv.tech.hdtv (More info?)

I just checked a previous post. A 2 hour uncompressed HD movie would take
up 1350 GB of space. Yes, 1.35 Terabytes. With current technology, the
only reasonable solution is to capture the HD in its compressed state.

--Dan

"dg" <dan_gus@hotmail.com> wrote in message
news:mEWad.29115$QJ3.5142@newssvr21.news.prodigy.com...
> Well, uncompressed HDTV is 1.5Gbps. Mull that one over for a bit. Its
not
> that nobody wants to design the obvious solution, its that nobody would
buy
> it because it would cost so much money.
>
> Compressed HDTV as we know it is around 12-19mbps, a much more reasonable
> rate to capture and save for later. That's what the tuner cards and Tivo
> units do. They have to capture the transport stream prior to it being
blown
> up to usable data. To compress 1.5Gbps to 19mbps on the fly, in real
time,
> is not as simple as we might like to think. To store it uncompressed
would
> require HUGE amounts of disk space.
>
> I have gone over this quite a bit, if you have any more questions just
ask.
>
> --Dan
Anonymous
October 14, 2004 1:27:58 AM

Archived from groups: alt.tv.tech.hdtv (More info?)

Ah, I understand now - thanks!
Too bad DVI spec didnt include a secondary pass-thru channel for the
compressed data.


brundlefly76@hotmail.com (Seth Brundle) wrote in message news:<53e2ec95.0410121059.5704565c@posting.google.com>...
> My major frustration with HDTV is this: why hasnt anyone yet designed
> an HDPVR
> which simply accepts component and/or DVI input????
>
> We've got OTA HD tuner card-based solutions, we've got DirecTivo HD
> for satellite tuning, and the cable companies have started launching
> their own mediocre cable-tuning HDTV PVRs...someone even has a QUAM
> (sp?) card cable HDTV tuner. There are firewire solutions emerging,
> but not every tuner has a firewire out...
>
> But I dont understand why no one just simply has a DVI-in or
> component-in card for PCs! This is exactly how TiVo took off - nearly
> every video system has a composite out S-VIDEO, or can be fitted with
> a converter for composite, so Tivo could be hooked up to anything.
>
> Seemingly, no one wants to design the obvious solution - a
> DVI/component-in PVR, with an IR blaster and composite/optical audio
> in.
>
> Anyone know *why*??
Anonymous
October 14, 2004 7:29:51 PM

Archived from groups: alt.tv.tech.hdtv (More info?)

"Seth Brundle" <brundlefly76@hotmail.com> wrote in message
news:53e2ec95.0410121059.5704565c@posting.google.com...
> My major frustration with HDTV is this: why hasnt anyone yet designed
> an HDPVR
> which simply accepts component and/or DVI input????
>
> We've got OTA HD tuner card-based solutions, we've got DirecTivo HD
> for satellite tuning, and the cable companies have started launching
> their own mediocre cable-tuning HDTV PVRs...someone even has a QUAM
> (sp?) card cable HDTV tuner. There are firewire solutions emerging,
> but not every tuner has a firewire out...
>
> But I dont understand why no one just simply has a DVI-in or
> component-in card for PCs! This is exactly how TiVo took off - nearly
> every video system has a composite out S-VIDEO, or can be fitted with
> a converter for composite, so Tivo could be hooked up to anything.
>
> Seemingly, no one wants to design the obvious solution - a
> DVI/component-in PVR, with an IR blaster and composite/optical audio
> in.
>
> Anyone know *why*??

This is exactly what 'content owners' don't want, and a major reason why DVI
was invernted. In addition to the very high data rate mentioned by other
posters, DVI from a HDTV tuner (from satellite, broadcast, cable, or DVD)
may also be encrypted with HDCP.

Component video is another matter. There are machines to record HD
component video. They cost $5k and the tapes are prohibivetly expensive
($25-$50 I'm not sure). Also the analog HD component video signal can be
digitally sampled and recorded. There is equipment to do this, but it is
very expensive and not intended for consumer use. Using large scale
integration LSI, and in a few years, it might be possible to do, this on a
consumer level. This is why 'content owners' would like to eliminate the
analog component outputs and just go with HDCP encrypted DVI.
!