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Discussion Starter · #1 ·
I've heard about the DirecTivo but I would really like a HDTV Tivo recorder only and continue to use my own HDTV receiver. I have always liked more components for greater flexibility. Does anyone feel the same and or heard of the future availability of a stand alone HD Tivo?
 

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There has been no news that one will exist. If one came out today it would not be very useful, for anything except recording OTA, and non scrambled quam. Once there are more sources with Firewire you should see a stand alone, but that is only starting to happen, so maybe next year.
 

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Discussion Starter · #3 ·
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Once there are more sources with Firewire you should see a stand alone,
What is Firewire and why does it effect the availability of a stand alone Tivo?
 

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Quote:
Originally posted by Steve Ruddy
What is Firewire and why does it effect the availability of a stand alone Tivo?
Firewire or 1394 is a connection type much like USB for a computer but much more bandwidth. It was first used to transfer Video between Camcorders to computers by Apple computer.


The reason why firewire is necessary is because currently it is the only connection type that supports transferring compressed HD video. There are currently no consumer level HD video recorders. The professional ones are very expensive.


When HD is sent over the wire whether it be via cable, sat, or OTA it is compressed with MPEG2 and the mpeg2 decoders in our HD tuners decode the signal and display it on our tv. The component cable's on most HD STB's output the uncompressed HD signal. The trick is to record the compressed signal, before it gets decoded. This is where firewire comes in, if you have a STB with firewire out you can record the Transport stream with the MPEG2 stream encapsulated in it to tape, or disk. Then play it back through the firwire to the MPEG2 decoder and watch it. Currently this is only possible with some STB if you have one consider yourself lucky. If you have D* or E* and you want one you can pay 169time.com ~1500.00 to mod your STB to add the firewire port.

Otherwise you can wait with the rest of us.


74 days and counting till April 1st 04
 

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Discussion Starter · #5 ·
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The trick is to record the compressed signal, before it gets decoded.
Why do we have to record the compressed signal. I have a stand alone TiVo now that I send a video signal via S cable right from my Panasonic DirecTV receiver. Couldn't you send the HDTV signal to a HD TiVo via a component cable that carries an uncompressed signal?
 

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Quote:
Originally posted by Steve Ruddy
Why do we have to record the compressed signal. I have a stand alone TiVo now that I send a video signal via S cable right from my Panasonic DirecTV receiver. Couldn't you send the HDTV signal to a HD TiVo via a component cable that carries an uncompressed signal?
It seems simple but it simple is not.


A normal TV signal is only 0.3 Mega Pixels, a 1080i signal is over 2 Mega Pixels. There are 30 frames per second. All the hardware that can do this is over $10,000.00. There is one DVHS deck that can do it for about 5K. But you are using a tape.


But don't take my word for it search this forum there have been many before you asking the same questions, and I think they have left disappointed. One day it will be possible. But even when it is possible our home encoders will not be as good as the professional ones use in the Industry, so we will still be better off recording the compressed stream. It will be better quality, and our Tivo's will be cheaper.


There is another alternative that I hope comes along, and that is that someone will make a Tivo that supports a Cable Card. Then we will be able to record HD via cable and not need another STB or firwire. Do a serach for cablecard on the forums.


Personally I love my ReplayTV, and I hope that they will come to the table with a HD recorder.
 

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To some extent, the HD Tivo does function as a stand-alone unit.


This is because it has ATSC OTA tuners. I believe (this needs corroboration) that it will work without a D* subscription, just as the HD STB's will work without a subscription.


[This needs to be verified, I haven't seen this spec yet.]


It will not handle cable HD signals and is in that sense not a stand-alone box.
 

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I believe (this needs corroboration) that it will work without a D* subscription, just as the HD STB's will work without a subscription.
This is not true. Read the big long HDTivo threads and you will see that someone (DirecTV, I'd guess) said that this will not be allowed.


Mike
 

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You guys waiting for an hdtv recorder should consider a dvd recorder, I use one and while the quality is not HD, its very close. My panasonic (fed via s-video from my samsung ota/Directv stb) records with the correct aspect ratio and looks fantastic! This will do me quite well until a reasonably priced hd recorder becomes available.
 

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Discussion Starter · #11 ·
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You guys waiting for an HDTV recorder should consider a DVD recorder, I use one and while the quality is not HD, its very close.
Thanks for bringing that up. I have a Sony KV-36XBR400 and if I can find a DVD player that will output a recording in 480i my TV will up-convert the image to 960i which looks very High Definition like compared to sending it a 480p signal thats not up-converted.
 

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Discussion Starter · #12 ·
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A normal TV signal is only 0.3 Mega Pixels, a 1080i signal is over 2 Mega Pixels. There are 30 frames per second. All the hardware that can do this is over $10,000.00. There is one DVHS deck that can do it for about 5K. But you are using a tape.
Thanks for the explanation Ben.
 

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How much longer are we going to say there isn't any hardward that can encode an hd signal for less than $10,000? How much bandwidth is per component channel? inline mpeg encoders?
 

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Quote:
Originally posted by rlsmith
To some extent, the HD Tivo does function as a stand-alone unit.


This is because it has ATSC OTA tuners. I believe (this needs corroboration) that it will work without a D* subscription, just as the HD STB's will work without a subscription.


[This needs to be verified, I haven't seen this spec yet.]


It will not handle cable HD signals and is in that sense not a stand-alone box.
Actually, it's not a stand-alone unit because it cannot encode MPEG-2.


The announced HD Tivo for DirecTV just records the encoded MPEG-2 bitstream as is. Thus, no need for MPEG-2 encoders.


Hong.
 

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And even when the price drops to reasonable levels on HD MPEG encoders, why would you want to put up with the quality degradation? Recording the digital signal directly would retain the original quality, and still be cheaper. I don't think anyone will ever see a need to make a PVR that does HD MPEG encoding.
 

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HD is already compressed when broadcast. There is no need for encoding at all - you just record the standard 19.2mbps data stream.


It's only analog NTSC that needs compression and that's why standard Tivos have a hardware MPEG encoder built-in.

Quote:
Originally posted by hongcho
Actually, it's not a stand-alone unit because it cannot encode MPEG-2.


The announced HD Tivo for DirecTV just records the encoded MPEG-2 bitstream as is. Thus, no need for MPEG-2 encoders.
 

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pdog, we were talking about (elusive) stand-alone units.


For the DirecTV HD Tivo, yes, you do not need encoder.


Hong.
 

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Quote:
Originally posted by hongcho
pdog, we were talking about (elusive) stand-alone units.


For the DirecTV HD Tivo, yes, you do not need encoder.


Hong.
Stand alone or not, there should never be a need for an HDTV mpeg encoder. Maybe one for SD to be backwards compatible.


You would not want to encode it yourself, the quality of a tivo HD MPEG encoder simply could not compare to the professional one that is used before transmitting the signal. It just does not make sense to decode the HD signal and then encode it again. For SD material it is necessary because the signal is not encoded before it is transmitted unless you are watching digital cable or satellite.


The only real reason to have an HD MPEG encoder after cable co's add firewire is to take advantage of the analogue hole and record content that is digitally protected.
 

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Quote:
Originally posted by jcblack
How much longer are we going to say there isn't any hardward that can encode an hd signal for less than $10,000? How much bandwidth is per component channel? inline mpeg encoders?
Inline MPEG Encoders?


Real-time MPEG encoding is VERY processor and memory intensive. This is not something you do with a little 8-bit processor... it requires a fast processor with lots of fast cache and lots of SDRAM. This, combined with the relatively expensive analog electronics to convert the high-bandwidth component output would make your suggestion unlikely.


If you every try to create your own 2-hour DVD from an analog video source (tape), you will see how much of your 3GHz computer's resources are used: most of it. Same process is going on there.
 
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