Ok lets see if I can answer some questions and hopefully clarify some things.
QUOTE(StoneRoses @ Jul 16 2004, 11:25 AM)
Notes:1. These setting is just a guideline you
SHOULD do compressibility test for your specific video source.
2. If you got unfavorable comp. test (and your source video is noisy) try improving the source video by using appropriate noise filter (I recomend using Avisynth frameserving for the source video)
I don't think compressibility tests are any longer valid. For instance, if your compressibility test says 80% compressible. And you end up with a average quant of 2.5 for the entire movie, can you say from that that it will look good? What if you got 50% compressiblity and average quant of 8? This information doesn't tell you much if anything. I have seen plently of movies which looked nice with a average quant of 8 and probably compressibility of probably < 50%. Then again I have seen some encodes with a average quant of 2.5 that look ugly.
I would also caution against filtering. Way too many people filter their movies like crazy because they think it is going to help. Usually, it doesn't help at all. Most codecs can deal with some noise. If you filter all that noise you are going to end up filtering out lots of detail and creating artifacts with the filters you are using. I can't remember the last time I have actually used a denoiser. My encodes nowadays are just crop+resize. But a denoiser, which is used in the codec could be useful since a video codec has much more information which it can make use of than most avisynth filters.
I have played around with a experimental version of XviD which uses coring to denoise the video see
http://ieeexplore.ieee.org/xpl/abs_free.jsp?arNumber=993441 It is very effective at removing noise without harming details too much and reducing bitrate. BTW I think it gives a PSNR increase too.
QUOTE(stephanV @ Jul 16 2004, 12:03 PM)
QUOTE(StoneRoses @ Jul 16 2004, 09:31 PM)
If encoding speed is your concern, I recomend using VHQ=1 + Turbo on the first pass (but VHQ-4 and Turbo off for 2nd pass). This will significantly speed up the 1st pass but leave minimal impact on the quality.
i thought VHQ settings were ignored during first pass?
http://forum.doom9.org/showthread.php?s=&threadid=76974 (syskins post)
They are disabled in the first pass by default, enable full quality first pass to be able to enable VHQ in first pass and qpel and other slower features.
QUOTE(smok3 @ Jul 17 2004, 03:47 AM)
I'am glad we came to the same conclusion, there should be noticeable difference even on higher bitrates. also, for my eyes Ouant. Matrix: H.263 is always the best choice, even for higher bitrates (but this could be related to the final viewing device - in my case that is mostly my 15,2 inch laptop lcd).
Yes, I use H.263 quant almost exclusively. At really low bitrates it begins to block more than a mpeg matrix like HVS good. That would be the only time I would switch to a mpeg matrix.
BTW there usually isn't much need to change settings too much from XviD's defaults. Here is what settings I usually use:
H.263 Quantization
Qpel // I use this on all movies except cartoons or anime.
B-frames 1, 1.5, 1.0
Packed bitstream off // only use it if you don't want decoder lag or want maximum standalone compatibility.
Chroma motion // if you use VHQ4 probably you may not need to enable this.
Turbo // give a nice speedup w/ qpel with very minimal quality loss.
VHQ 4
I-frame interval 240 // 10x the fps is a good rule of thumb.
All min quantizers to 2
Trellis quantization
I don't want to say these are the best settings because it varies obviously from movie to movie and from person to person. But they have worked well for me. I would caution against enabling things like AQ or GMC. AQ may harm quality as it is still a little buggy and GMC likely will not increase quality much and will slow things down a lot.