more newb questions

[codename_46]

I have v.26 of GKnot. I must say it works very well. Tons of thanks to the guys who put it together :)
The guides are also well done. I was successfully backing up my DVDs after only 2 hours of study and reading. Initially I had a ton of questions but was able to get answers to most of them in the forums. However I still have 2, please don't flame me if they've been answered before but I wasn't able to locate them.
1. Whenever I run the encoding job in GKnot for the audio instead of choosing MP3, custom Parameters and then selecting the recommended settings in the drop down box. I've been selecting MP3, 128 kBit/sec. average Bitrate. Is there an advantage to choosing custom Parameters instead of the other? Or is it a preference thing?
2. After running the compressibility check I usually get values around 40%. The only effective way I've found to increase it up to the 60% I like to encode at is to reduce the resolution. I don't have DivX 5 Pro so I can't use B-frames. Is reducing the resolution pretty much it or is there something else I should try?

[jggimi]

The difference between Doom9's audio recommendations and the defaults are minor, but I think they help when going from 5.1ch to stereo. You'll find the descriptions of the addional Azid operands -- the "-L -3db -c normal" in your Docs folder, in the Azid.txt file.

There are 3 alternatives to running with a low compression check value.

1) Install DivX 5.02 Pro to exploit B-frames (bi-directional encoding), which will improve compressibility significantly.

2) Drop to a lower resolution, which you are already aware of, and as you know, you may not like the results.

3) Move from 1-CD to 2-CD encodings.

[ArdenDag]

I agree with jggimi, B frames are your best friend for low bitrate encodes. They tend to blur a bit, but that also aids in compressibility. Also think about moving towards editing in your own filters for use in encoding. There are a lot of filters that can give you a visually pleasing encode even with a low compressibility check %.

Yes, also, if you intend to keep this encode for personal use, and don't mind the extra disc (or larger file-size if it's only for your computer) then go for the higher file-size :)

EDIT:

if you intend to get DivX 5.02 pro, go to the DivX forum and read about the ad-ware, and doom9's solution to it ;)

[ChannelK]

Also try divx5enc, my rips have increased in quality heaps with the assistance of this little beaut in conjunction with GKnot to start the avs and then some more minor editing before comp tests.

http://forum.doom9.org/showthread.php?s=&threadid=22532