[MPlayer-users] Re: Problem Encoding Solid Color Objects With LAVC MPEG4

Angel angel at knight-industries.com
Tue Sep 23 12:04:16 CEST 2003


Hi all,
	I appreciate all the suggestions that have been offered on this list. 
Unfortunately, I have tried every one of them and none have made any 
noticeable improvement in the video quality. One thing I did notice is that 
while the artifacts are clearly visible when I view the movie on my computer 
monitor... they are FAR more pronounced when I watch the movie on my T.V.

Rich wrote:
> I doubt this is the main cause of your bad quality, but odd crop
> offsets in the vertical direction are NOT valid. You will misalign the
> chroma plane resulting in bogus output and reducing the effectiveness
> of motion estimation. BTW, it makes more sense to crop before scaling
> (much faster).

> Also you might try getting rid of qmin/qmax. The default qmin of 2 is
> much better in most cases. I don't see where you set qmin=1 for the
> DivX5 encode, so that might very well be the cause of your problem.

I appreciate the odd cropping value tip Rich; however, I tried your suggestion 
of removing the qmin/qmax and the results were noticeably worse. 
Consequently, that is the clip I used as the example.

Corey wrote:
> Is it possible for you to upload the source file to some
> publicly-accessible http or ftp server? I'm always curious to mess
> around with files that are problematic to encode.

Yes. I tried multiple times to upload the source/results to 
ftp.mplayerhq.hu/incoming but I couldn't get it to work. On the last attempt 
I noticed the error message I received said that the device was out of space. 
I've put the files on my server. You can download them from the following 
URL: http://www.knight-industries.com/bad_boys. If you get the problems with 
the ftp server fixed... let me know and I will upload the clips there if you 
want.

-Angel



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