[XviD-devel] DivX5.03 Nth Pass encoding

Cami xvid-devel@xvid.org
Mon, 27 Jan 2003 11:21:03 +0200


| | Can anyone tell me if xvid having such a feature will
| | improve image quality? or is it not nessasary / wont make any difference?
| 
| Possibly three-pass would be better than two, if we analysed e.g. blocking 
| artefacts from second pass. But if it's worth the extra time? I don't
| know.

I'm sure everyone will have their own opinion here, mine personally,
would be to have that possibility, considering a 2 hour movie takes
a little over an hour to encode (2pass+qpel+chroma), so an extra
pass wouldnt hurt at all..

| What might be cool is a new feature from transcode: "On the fly parameters
| changes". Create a logfile with encoding setting in advance (not only
| "start of credit, end of credit", more like a movie script, including
| not only quantizers, but also things like motion search method, GMC,
| maybe quant matrix (ratecontrol could of course still modify
| quantizers).

Can anyone tell me if GMC improves or degrades image quality?
Half the people i've spoken to say its a good thing, the other half
dont.. 

While i'm babbling away here, the credits encoding part of xvid,
more specifically the 'Encode credits in greyscale', is that suppose
to encode the selected frames in _completely_ black and white?
If so, its not working very well.. Its leaving green smudges/artifacts
over some of the letters..

++C