mvinfo file

[maormini]

Hi!

What do we need it for?
Could I live without it, I heard that it causes some crashes while doing 2-pass encodings!

[DJ Bobo]

I always enable it and I've never got problems because of it.

[N_F]

The mvinfo file speeds up your encoding speed at the second pass.

I've never had any problems with it and I see no reason whatsoever not to use it.

[Acaila]

..and I see no reason whatsoever not to use it.Since the codec re-uses the motion vectors from the first pass instead of recalculating them with all the correct info from the second pass, they will be slightly "off". Hence you will get a (small, maybe not even noticable) quality degradation.

[maormini]

Originally posted by Acaila
Hence you will get a quality degradation.

Is that a fact! Wow then forget the improvement in speed, I leave it overnights anyway, I'm looking for the best possible quality while keeping a certain file size.

[Acaila]

Before everyone starts thinking now that using an MV-file sucks, don't forget I said small, maybe not even noticable degradation.

It's probably along the lines of using DVD2AVI's 32 bit or 64 bit IDCT. Using 64 bit gives you a slightly higher quality (at the cost of speed, again), but I've never met anyone who can tell the difference.

[TheXung]

Since the codec re-uses the motion vectors from the first pass instead of recalculating them with all the correct info from the second pass, they will be slightly "off". Hence you will get a (small, maybe not even noticable) quality degradation.

Are you sure about that? I have done tests on full movie encodes and found them to be byte for byte exactly the same. That shouldn't happen for full length movies. It's not like Xvid's hinted ME, you can't get any movie to be byte for byte the same with xvid's

[N_F]

Originally posted by TheXung


Are you sure about that? I have done tests on full movie encodes and found them to be byte for byte exactly the same. That shouldn't happen for full length movies. It's not like Xvid's hinted ME, you can't get any movie to be byte for byte the same with xvid's

I assume you did this test by first doing a first pass with the mvinfo-file checked. Then you did two second-pass tests, one with the mvinfo checked and one without it. Correct?

[eXistenZ]

Originally posted by maormini
I heard that it causes some crashes while doing 2-pass encodings!

I've experienced crashes using Xmpeg 4.X on a Win XP, Athlon CPU box. Disabling MVinfo.bin crashes disappeared...

Maybe it's just this combination to be buggy, not the other ones...

So, simply, if you don't experience crashes you can leave it.

Bye, eXistenZ