So what's wrong with D-VHS? - Page 9 - AVS Forum
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post #241 of 251 Old 05-25-2006, 08:07 AM
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New question! :)


What about MPEG-2 and MPEG-4. I'm aware that DVHS decks use MPEG-2, and I remember reading about cable/sat/broadcast companies moving to MPEG-4 as it's more efficient/compressed. Will this be an issue?
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post #242 of 251 Old 05-25-2006, 08:09 AM
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Yes and no. According to some sources, you can archive MPEG4 onto a DVHS tape. The problem is that it isn't going to be able to play it back decoded since the decks lack an MPEG4 decoder. So at that point the deck becomes an archival device and not a player.

Someday maybe I'll actually WATCH my projector...
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post #243 of 251 Old 05-25-2006, 08:26 AM
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Quote:
Originally Posted by madpoet
Yes and no. According to some sources, you can archive MPEG4 onto a DVHS tape. The problem is that it isn't going to be able to play it back decoded since the decks lack an MPEG4 decoder. So at that point the deck becomes an archival device and not a player.
Do the TVs have MPEG4 decoding for the raw signal over firewire (since the MPEG2 decoding is done for the component outs on JVCs)?
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post #244 of 251 Old 05-25-2006, 10:58 AM
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Quote:
Originally Posted by Brian81
Do the TVs have MPEG4 decoding for the raw signal over firewire (since the MPEG2 decoding is done for the component outs on JVCs)?
Thats an interesting question -- the answer appears to be no. I don't think mpeg4 decoders have been included in the vast majority of today's hdtvs due to cost factors, and the fact that cable companys have not been using mpeg4.

There are mpeg4 cablecards in the works. Would an mpeg4 cablecard allow a tv to decode an mpeg4 stream sent from a dvhs player to the tv via firewire? My relatively uneducated guess would be no.
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post #245 of 251 Old 05-25-2006, 01:38 PM
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Quote:
Originally Posted by dc10forlife
Thats an interesting question -- the answer appears to be no. I don't think mpeg4 decoders have been included in the vast majority of today's hdtvs due to cost factors, and the fact that cable companys have not been using mpeg4.

There are mpeg4 cablecards in the works. Would an mpeg4 cablecard allow a tv to decode an mpeg4 stream sent from a dvhs player to the tv via firewire? My relatively uneducated guess would be no.
CableCards ARE NOT encoders, they simply supply the encryption keys necessary for a QAM tuner to read an encrypted digital feed, they do not actually read the MPEG-2 or MPEG-4 streams.
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post #246 of 251 Old 05-25-2006, 01:40 PM
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Quote:
Originally Posted by Brian81
Thanks for the info.

Other info from what I hopefully understand..
If the cable box has firewire, and I run that to the tv, I should be able to connect the DVHS deck to the tv also with firewire and should be able to record the same as if the DVHS deck was connected directly to the cable box.

I do want the interactive tv guide feature, so I'd definitely want the cable box. $3-5/mo. for a cable card is nothing, so if the cable box's firewire is buggy then I'll just rent both.

Questions: Does the cable card send the analog channels over as digital also? Is it possible to record analog SD channels like those from the "Ant" inputs to the DVHS via firewire?



Going to jump on the TVA Samsung PB bandwagon today, probably.
Theoretically the TV will loop the STB's firewire data to your DVHS deck, since firewire was built for daisy-chaining, but you never know. The CableCard has nothing to do with firewire or analog channels, so only digital channels will be output from an HDTV via firewire.
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post #247 of 251 Old 05-25-2006, 01:41 PM
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Quote:
Originally Posted by Brian81
Thanks for the info.

Other info from what I hopefully understand..
If the cable box has firewire, and I run that to the tv, I should be able to connect the DVHS deck to the tv also with firewire and should be able to record the same as if the DVHS deck was connected directly to the cable box.

I do want the interactive tv guide feature, so I'd definitely want the cable box. $3-5/mo. for a cable card is nothing, so if the cable box's firewire is buggy then I'll just rent both.

Questions: Does the cable card send the analog channels over as digital also? Is it possible to record analog SD channels like those from the "Ant" inputs to the DVHS via firewire?

Going to jump on the TVA Samsung PB bandwagon today, probably.
Most cable systems are duplicating the analog channels on the (usually encrypted) digital tier
so that they can deploy lower cost all-digital STBs and DVRs.

You didn't say where you are located or which cable system....
So check your local thread to see if your cable system has performed the DIGITAL SIMULCAST upgrade.

Using STB, DVR or CableCard, channel surf through the analog channels--analog channels come in immediately.
If they take longer (1-2 seconds) to lock-in, they are digital and hence should be output via Firewire (same as CH100+).
BTW: The analog channels are still available via direct connection to NTSC tuner.

In order for a device to output Firewire for analog channels, it would need to perform an MPEG2 Encode function.
I don't know of any Cable STB that will do this and it's not a CableCard function.
With Firewire being so new (and mostly disfunctional) in HD-DVR's, it is unknown if the built-in
MPEG2 Encoder has been used to convert analog channels for output via the Firewire channel.
Although unlikely, the HDTV theoretically could perform this function (check your manual).
===============================================
re MPEG4: so far it is only available in MPEG4 capable D* and E* receivers--none of which have Firewire. So the issue is moot.

The DVHS Recorder is a simple data stream recorder/player--it shouldn't really care if the data is MPEG2,
or MPEG4 encapsulated in MPEG2 headers...
And of course today's HDTVs wouldn't know what to do with an MPEG4 data stream anyway....
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post #248 of 251 Old 05-25-2006, 03:59 PM
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Quote:
Originally Posted by holl_ands
In order for a device to output Firewire for analog channels, it would need to perform an MPEG2 Encode function.
I don't know of any Cable STB that will do this and it's not a CableCard function.
With Firewire being so new (and mostly disfunctional) in HD-DVR's, it is unknown if the built-in
MPEG2 Encoder has been used to convert analog channels for output via the Firewire channel.
I am positive the Motorola 6412 outputs (MPEG2 encoded) analogs over Firewire. I've captured directly to my PC with it. Don't know about any other models.
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post #249 of 251 Old 05-25-2006, 05:11 PM
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Quote:
Originally Posted by twitchee3
CableCards ARE NOT encoders, they simply supply the encryption keys necessary for a QAM tuner to read an encrypted digital feed, they do not actually read the MPEG-2 or MPEG-4 streams.

OK, assuming that is true, can QAM tuners decode mpeg4?

Whats the purpose of an mpeg4 cablecard?
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post #250 of 251 Old 05-25-2006, 08:26 PM
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Quote:
Originally Posted by dc10forlife
OK, assuming that is true, can QAM tuners decode mpeg4?

Whats the purpose of an mpeg4 cablecard?
There are currently no HDTV's with MPEG-4 encoders, so no current QAM equipped TV's cannot deal with MPEG-4 (H.264). CableCards simply decode the encrypted data sent by the cable company and send the unscrambled data to the devices (usually an HDTV, but sometimes a stand alone STB or DVR) built in MPEG-2 decoder for display or output over firewire. CableCards ARE NOT the video decoders, they simply unscramble the data being sent to the decoder so the decoder can decipher it properly.
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post #251 of 251 Old 05-28-2006, 11:42 AM
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Quote:
Originally Posted by Rudy1
I use a Sony remote with a built-in timer to enable recordings on my Mits from a Motorola STB. It's the RM-VL1000.
I went with the Sony RM-AX4000 from B&H Photo, works like a charm, PC programable with 8 timers and fairly cheap for what you get.

It solves all my timer recording issues with the Mitsu 1100 and Moto 6412. Turns them both on and off, switches to the correct channels/inputs and then turns them off, multiple events if I want. Strong IR signal, doesn't need to be pointed at the components.

I wouldn't want this for my everyday remote because its kind of big and heavy (unless you like 2 handed touch screens) and the PC software isn't nearly as user friendly as my MX-800 is. But once you get used to it it's fairly flexible.
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