[gpttigers]

Just as a VCR and DVD-R record programming, will it ever be possible to have a recorder that is capable of having a DVI or component input and output which serves as a pass through? Doing this would make everyone's life a lot easier.


After all, it is the same signal that your TV is using to create the HD picture. Why can't that signal be recorded? Maybe there will be some new technology that will facilitate this.

 

[dt_dc]

It's possible right now. The solutions just aren't ideal ... and probably won't ever be.


There's W-VHS ... which works just like you described (like a VCR). Capture the analog signal in a way that can be played back. It's relatively inexpensive (used units have been found in the $1k price range). You've got component inputs so you can record from anything out now ... don't have to worry about DRM ... etc. But, you've got many of the same drawbacks as VHS analog recording ...
http://pro.jvc.com/prof/Attributes/f...l_id=MDL100250


The more elegant solution is to caputure digitally (like a DVD-R). However, this is where things get very expensive. You either need the hardware that can handle an uncompressed digital stream (hard drives , CPU, etc.) OR you need to compress the stream up front. There are several products out there that can do this ... taking either (or in some cases both) approaches ... but they are VERY expensive.


Yes, the technology will improve / become cheaper over time but ...


The cheapest / most elegant way to record HD is going to be to capture the original, compressed stream. It's hard to see where a DVI or component recorder is ever going to reach the production levels needed to drive prices down ... when a Firewire recorder is always going to be cheaper and provide better picture quality.

 

[gpttigers]

Definitely keeping the stream digital is going to give you the best quality picture. This W-VCR sounds like it is capturing an analog stream through component. Why can't they create a machine that captures via DVI. I though that DVI was a pure digital stream. Doesn't DVI stand for digital video Interface?


With hard drives getting bigger and bigger and relatively low prices, this would seem like the way to go to me. The technology to convert/capture this stream should be there or may be there in the future.

 

[mdv]

DVI-D is digital but it's uncompressed. Do the math and you'll find out that it's too much data. 1920 x 1080 with 24 bits per pixel at 30 Hz comes out to like 200 Mbytes/sec. OK, half that for interlaced but still...


Even if you had a fast enough device, where would you put all of the data? You'd have to compress on the fly. That's why recording the original compressed stream is really the way to go.





Mark

 

[gpttigers]

I had no idea it was that big of a file. Are you sure your calculations are correct? 200 gig per second? If that number is correct, I now understand why IEEE is the way to go.

Quote:

Originally posted by mdv DVI-D is digital but it's uncompressed. Do the math and you'll find out that it's too much data. 1920 x 1080 with 24 bits per pixel at 33 KHz comes out to like 200 Gbytes/sec. OK, half that for interlaced but still... Even if you had a fast enough device, where would you put all of the data? You'd have to compress on the fly. That's why recording the original compressed stream is really the way to go. Mark

 

[dt_dc]

Here's an uncompressed recorder:
http://www.doremilabs.com/products/v1uhd.htm


It has HD-SDI inputs ... but you can get Component -> HD-SDI or DVI -> HD-SDI converters (again, not cheap).


An external RAID array with 14 120gig drives will get you as much as 6 hours (and as little as 2 hours) HD recording time ... dependent on format, bit rate, etc:
http://www.doremilabs.com/pdfcharts/uncomp.pdf


Should also double as a nice heater for your house ...

 

[fire407]

Quote:

Originally posted by gpttigers Just as a VCR and DVD-R record programming, will it ever be possible to have a recorder that is capable of having a DVI or component input and output which serves as a pass through? Doing this would make everyone's life a lot easier.

Firewire connections give you exactly the kind of pass through you are talking about. I can watch HD from my Samsung tuner thru my DVHS machine and record it if I want to. It actually works the opposite way too where I watch the DVHS playback through the Samsung tuner. The problem is that other than Mitsubishi, nobody wanted to make a firewire network. The Mitsubishi model is brilliant because it allows all of your equipment to be daisy chained with a single cable between components. The firewire cable carries audio, video, and control all in one cable. However, Mitsubishi's network idea has been all but shot down and very few equipment makers will put firewire on their equipment, and even when they do(such as Motorola) it's only a one way connection. There are no DirecTV receivers with firewire--except for the 169time mods, and Dish is still uncertain about including working firewire ports. The great firewire network technology has been available for years now, but for some political reasons it hasn't been allowed to flurish. I don't own a Mitsubishi TV, but the demonstratons I've seen of their network have me convinced that it could have been great.

 

[gpttigers]

Sounds like a lot of connectivity issues. Someone need to get on this.


In response to dt_dc's post, I could use a new heater living in New Orleans. The high today is only suppose to be in the mid 90's with 90 percent humidity.


Thanks to everyone for responding, I am now starting to grasp the issues with compressed and uncompressed.

 

[HDTVFanAtic]

Quote:

Originally posted by dt_dc Here's an uncompressed recorder: http://www.doremilabs.com/products/v1uhd.htm It has HD-SDI inputs ... but you can get Component -> HD-SDI or DVI -> HD-SDI converters (again, not cheap). An external RAID array with 14 120gig drives will get you as much as 6 hours (and as little as 2 hours) HD recording time ... dependent on format, bit rate, etc: http://www.doremilabs.com/pdfcharts/uncomp.pdf Should also double as a nice heater for your house ...

I saw this unit at the NAB in Vegas back 45 days ago. I immediately said this will do exactly what I want.....then I saw the $35k base price.

 

[mdv]

Quote:

Originally posted by gpttigers I had no idea it was that big of a file. Are you sure your calculations are correct? 200 gig per second? If that number is correct, I now understand why IEEE is the way to go.

I did make a mistake. I was using KHz instead of Hz for refresh rate. It's more like 200 Mbytes/second. Still a lot of data.


Mark

 

[dirk1843]

How many years ago would we have thought a Tivo would have been too expensive??


If the powers-that-be (Hollywood and their antipiracy watchdogs in our capitol) ever allowed recording of analog outputs then I feel technology would catch up where MPEG ecnoders powerful enough to handle HD would be affordable.


But the "analog hole" is a huge thorn in the sides of the movie companies because it can not be controlled. Don't we all remember the talk of "downrezing" the HD output of our STB's??


So in all likely hood, it will never happen...................

 

[Ken H]

HDTV recording is best achieved with the ATSC compressed data steam. Forget about analog, uncompressed, etc.

 

[HDTVFanAtic]

Quote:

Originally posted by dirk1843 How many years ago would we have thought a Tivo would have been too expensive?? If the powers-that-be (Hollywood and their antipiracy watchdogs in our capitol) ever let analog HD happen then it could happen. But the "analog hole" is a huge thorn in the sides of the movie companies because it can not be controlled. So in all likely hood, it will never happen...................

What the hell are you talking about?


Analog HDTV was slotted to happen in mass by the early 90s. HBO promised a 24/7 HD Channel by the end of 1989. It was a done deal for the roll out in the early 90s in the USA.


But Digital came on full force with the CD and then the advent of DVDs. Smart Engineers quickly figured out not to follow Japan into Analog HDTV. And thus, the decision was made to wait (wisely) for digital HDTV. Look at your OTA Digital versus the old 480 - Ghost and all. Imagine that noise and mess in a HDTV system....NOT!!!!!!!!!!


And after the US waited and went digital HDTV, Japan's HDTV system looked horrible in comparison - (think composite out vs dvi) and thus Japan has been scraping their Analog system after a very short life span to go digital.


Analog ain't coming - it went 15 years ago.

 

[bdraw]

Quote:

Originally posted by fire407 The great firewire network technology has been available for years now, but for some political reasons it hasn't been allowed to flurish. I don't own a Mitsubishi TV, but the demonstratons I've seen of their network have me convinced that it could have been great.

I have a Mitsubishi TV and I will tell you that it is great and will be.


The reason why DBS doesn't have firewire may be political, but the reason why TV's don't have it is strictly economics. In order for a TV to have firewire it has to have a mpeg decoder if it has an mpeg decoder it might as well have a HDTV tuner.


Since 50% of all TV's 36" and larger are mandated to have ATSC tuners by July 1st 2004. This means that 50% will have mpeg decoders. The only manufacturer that released a TV with integrated tuner(this year) without firewire is Panasonic RPTV(don't ask me why). All of the other tv's with integrated ATSC tuners have firewire. Now that anyone can request a cable STB with firewire, and a used DVHS deck can be bought for ~$200.


This only leaves the DBS providers, and a AV receiver/amp.


All this has me convinced that it will be great.

 

[Thomas Desmond]

> Analog ain't coming - it went 15 years ago.


Nonetheless, the majority of us are still viewing those digital HDTV signals in analog form via analog connections to our HD televisions. Most of the current installed base of HD-ready sets lack any sort of digital connections, which mean that analog connections will be with us for years to come.


Thus, the movie studio references to the so-called "analog hole".

 

[rogo]

"Most of the current installed base of HD-ready sets lack any sort of digital connections"


This is already wrong. As of the year end 2003, the majority of HD-ready sets have DVI/HDCP.


By the end of 2005, it will be >80% of all HD-ready sets.

 

[alk3997]

Well, analog recording may not matter if this type of scheme catches-on and is then applied to component video outputs (as well as the mentioned SD outputs),

http://www.hbo.com/corpinfo/cgmsafaq.shtml

 

[dt_dc]

Quote:

Originally posted by alk3997 Well, analog recording may not matter if this type of scheme catches-on and is then applied to component video outputs (as well as the mentioned SD outputs), http://www.hbo.com/corpinfo/cgmsafaq.shtml

Thanks for the link ... very interesting that they've flipped on CGMS-A. Windows Media Edition respects CGMS-A (I think you can still capture the video ... but you can't burn to DVD or send the file to someone else) ... interesting to know how other equipment handles CGMS-A and what effect this may have ...

 

[Erik Garci]

Quote:

Originally posted by dt_dc interesting to know how other equipment handles CGMS-A and what effect this may have ...

Couldn't you just use equipment that doesn't support CGMS-A?

 

[dirk1843]

Quote:

Originally posted by HDTVFanAtic What the hell are you talking about? Analog HDTV was slotted to happen in mass by the early 90s. HBO promised a 24/7 HD Channel by the end of 1989. It was a done deal for the roll out in the early 90s in the USA. But Digital came on full force with the CD and then the advent of DVDs. Smart Engineers quickly figured out not to follow Japan into Analog HDTV. And thus, the decision was made to wait (wisely) for digital HDTV. Look at your OTA Digital versus the old 480 - Ghost and all. Imagine that noise and mess in a HDTV system....NOT!!!!!!!!!! And after the US waited and went digital HDTV, Japan's HDTV system looked horrible in comparison - (think composite out vs dvi) and thus Japan has been scraping their Analog system after a very short life span to go digital. Analog ain't coming - it went 15 years ago.

I didn't make my post clear.........I meant recording of the analog outputs of HD tuners....using methods similar to what Tivo and other pvr's do with NTSC today.


While a pure digital product would be best, it does lead to tying oneself to one service (dish, D*, cable, etc.) when a standalone version would allow you to use either or all...........also precludes most copy protection schemes, which IMHO is why we haven't seen such a product. Tivo claimed to be working on one a few years back, but now say it will never happen...........


I will amend my original post to clear it up...........