What limits 4:2:2? Technically speaking

[techno935]

This question extremely technical:

Is 4:2:2 software driven? Hardware driven? Such a thing as 4:2:2 being in high demand, leads me to a question. Are there modifications that can be done to existing hardware and/or software to allow 4:2:2? I know there has to be a research section somewhere out there where someone is actually trying to get this going in an existing IRD. I can't understand why it's not just something simple that can be added in a command line of software.

 

[SatPhreak]

I don't know but with that being said I believe it is software because it works on dvb cards with the computer running software. Perhaps the recievers aren't powerful enough.

 

[vfrjim]

On a receiver, it requires an additional chip to process it (mpeg decoding) and most receiver manufacturers like a 1 chip design box to keep costs down from my understanding.

 

[brentb636]

If you google on "4:2:2 chroma chip ", you will find that a large number of encoder and decoders chips are available. I suspect that the Quali-TV has such a piece of hardware, so that the cpu doesn't have to decode the 4:2:2 chroma signal. Our pc-based systems, which do the decoding in software using codecs, have much more powerful cpu's than do the dedicated stb's. I've got a feeling the answer is as simple as that. If the mfg wants to include the 4:2:2 chroma in his stb, the circuit design has to include a decoder chip for that video.

 

[skysurfer]

This question extremely technical:

Is 4:2:2 software driven? Hardware driven? Such a thing as 4:2:2

Format driven. In 4:2:2, double the amount of vertical color information is transmitted compared to 4:2:0 format.

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