MPEG2 DC precision
 

I've noticed that newer versions of ffvfw (ffdshow encoder now, but not for long ;) ) have settable MPEG2 DC precision to 8, 9, 10, 11 bits. It does affect quality a bit (higher value = higher quality + smaller filesize).
However I can't find this feature in mencoder, and all encodings are made at precision 8.
Does anybody know if its possible to set other than 8 DC recision :?:
And secondary is 11bit encoded file still full DVD compliant (maybe stupid question :oops: ) :?: ;)

Re: MPEG2 DC precision
 

That's a little more complicated than that, as always in video editing.

The only prototype level allowed on DVD is MP@ML. This prototype allows only DC up to 10. 11 is available only in higher prototype (HP@ML and Y422@MP)

The question wasn't so stupid :-)

Re: MPEG2 DC precision
 

Thx Phil.
I've made some tests and that was my results. But of course there's always differend end for differend story ;)

Re: MPEG2 DC precision
 

First who was looking for that is Kwag (as I know it). Later many others try to find out something in this sense. But it seems that no way.
:(

Re: MPEG2 DC precision
 

The complication is not only in the encoder, but also in the decoder.
A lot of MPEG2 decoding chipset doesn't support DC=11. They decode anything with a 10 bits precision. That means that you have clipping/rounding in the values.

It's like having a picture in 32bits colors but a video card that only displays 24bits

:arrow: Where are the benefits ?

Re: MPEG2 DC precision
 

Aha. Many thx Phil, for pointing this. I assume that if ffdshow can encode in 11 bits then it also can decode in 11 bits. AFAIK mpeg1/2 decoder is still buggy but Milan is workin on this.
I understand that in terms of standalones, it is beter (safer) to encode in 10 bits, to avoid "flowers" :?: ;)

Re: MPEG2 DC precision
 

In a general way of speaking : Yes. Even if good surprise is always possible.