D* is going to MPEG4 but they never went to MPEG2. They adapted MPEG1 to the multiple stream programming environment. Some people refer to it as MPEG1.5 . E* is currently following the MPEG2 standard.Ray_Air said:
JL
Mpeg 4
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JL
Personally I don't know what series mpeg chip is or was installed in DirectTV receivers but mpeg is downward capatible. Meaning mpeg2 can still decode mpeg1 and mpeg4 can decode both mpeg2 and 1.
If any receiver has HD capability and/or digital OTA tuner then it would have to be mpeg2 at the very least because that's the standard for digital broardcasts and mpeg1 can't do high resolution formats (as Ray_Air stated "MPEG1 roughly VCR quality").
If any receiver has HD capability and/or digital OTA tuner then it would have to be mpeg2 at the very least because that's the standard for digital broardcasts and mpeg1 can't do high resolution formats (as Ray_Air stated "MPEG1 roughly VCR quality").
Well, if they honestly wanted to they should be able to upgrade them. after all mpeg is only just a codec, and codec's should be able to be upgraded. Again I'm a computer guy not a satellite guy. So I could be waaaaay off base on this. Depending on the chip, if it is a flashable chip, the chip could be upgraded. True some chips are ROM's and can't be upgraded. But in my opinion I can't see them using a ROM chip on a technology that they know will change.
My take on MPEG4
There have been rumors about this for months. Would E* start leasing 942's if they had to take them back really soon?
There are a few possiblities on how this can be done.
1) There are two hardware decoders in the 942.
2) The current decoders can be flashed.
3) The boxes can reprogrammed with the appropriate codecs.
Maybe someday in the next three months we will know one way or the other. I don't think anybody has a clue what the answer is, but it is possible.
Chris
There have been rumors about this for months. Would E* start leasing 942's if they had to take them back really soon?
There are a few possiblities on how this can be done.
1) There are two hardware decoders in the 942.
2) The current decoders can be flashed.
3) The boxes can reprogrammed with the appropriate codecs.
Maybe someday in the next three months we will know one way or the other. I don't think anybody has a clue what the answer is, but it is possible.
Chris
They were produced at some non-zero cost and every dollar they can make on them via lease or sale and in programming subscriptions is a dollar that covers that production cost. Trashing them (although enjoyable to those who have suffered the 942 bugs) would cost E* more than allowing them to be used for a year and then replacing them with MPEG4 units.kosair said:
JL
bpickell said:
They use ASICs. Some of the ASICs go back several years. The number of cpu cycles required for MPEG-2 vs MPEG-4 is something like 3 or 4 to 1. I don't recall the exact number. That's not counting the code size, and you have to store the code for both MPEG-2 and MPEG-4, you have to detect in the data stream MPEG-2 or MPEG-4, and you have to be able to crunch both.
Now go back 5 years and plan for all this. It's simply not not practical. Why? Because MPEG-4 wasn't even locked down 5 years ago, and the horsepower didn't exist 5 years ago etc etc etc.
I'm a computer guy, and I understand all this. It helps that I also write for a consumer electronics publication (see avatar) so I keep abreast of the industry. It's a far different world for an appliance (your satellite receiver) versus a general purpose computer. Then again, a 5 year old computer has issues running the latest software too
Regards,
See now that make sense. I didn't know that Mpeg2 had been around that long. I figured it was another one of those codecs that they are updating every few months or so. I am quite new to satellite jargon, and have been in the computer networks industry for 9 years.
Hardware is faster than software
These chips are actually special processors simular to a graphics core on your computer's graphic card. Although it's possible to do decoding by software method, the CPU and memory would have to be extremely fast to do it in real time. That probably would add $1000 (just speculation) to the cost of these receivers so it's much cheaper to add a $35 mpeg chip instead.bpickell said:
bpickell said:
MPEG-2 has been around for roughly 10 years. I don't know the exact date of its introduction, but it was around prior to DVD-Video's release.
What you are asking for is the equivalent of asking to get a firmware upgrade to add Gigabit ethernet support onto a 10/100 router. It ain't gonna happen ;-)
I thought mpeg4 didn't save that much over mpeg2 when its done in real time. I encoded a mpeg4 file once on my computer and to get any space savings I had encode the source once and then encode it again. During the first pass it creates a text file with a bunch of numbers and it does something with that file during the second encoding.
kb:
The relationship between your computer and commercial encoders is like the relationship between a pocket calculator and your computer.
In short, there is no comparison.
Best,
The relationship between your computer and commercial encoders is like the relationship between a pocket calculator and your computer.
In short, there is no comparison.
Best,
Also, there are different "flavors" of MPEG-4. Sats will use AVC (goes by other names also- H.264, etc). Earlier versions of MPEG-4 had lower PQ than MPEG-2 at high data rates, but better PQ at lower data rates. Now, MPEG-4 probably beats MPEG-2 in PQ across the board, plus has better EDAC. These earlier version were incorporated in a lot of computer software. See the Sept issue of Home Theater magazine for a good article on this.
