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ozy311
30th August 2005, 02:25
Hello All, I have been lurking for quite some time and wanted to post a quick question. I have searched but have had a hard time finding my exact question. I encode my DVD collection to Divx for playback on my 63" TV. I have a 2TB server, so I have no need to target any size. I want to use the best balance between quality and space saving. I have found that 75% on 2.15 looked fine.

My questions are:

1) Why in 2.16 did you choose to set Divx 6 to 60%? I am in the middle of doing a compression comparision between 2.15 & 2.16. Currently on 2.15 I re-encoded "DreamCatcher" using Divx 6 @ 75% & 60%. The size was 1869MB vs 2361MB. Side - by - side comparisions show a big difference between the two. The 75% version has deeper contrast and less blocking / banding. Did you chose 60% because it more closely matched what Xvid looks like at 75%? I did notice that 75% Divx6 vs 75% Xvid resulted in the Divx file being larger and better looking using 2.15.

2) Can you define what exactly the quality settings are passing to the Divx encoder? And perhaps what does the quantization settings do to effect the output and if they were tweaked from 2.15 to 2.16? I was using normal GK, and when i opened the Divx codec setup's advanced settings, i saw what seemed to be the settings you pass to the codec using AutoGK. Very interesting.

Thank you for your wonderful program. Truely amazing.

jggimi
30th August 2005, 03:22
Hello, and welcome to Doom9's forum.

I'm moving this to the AGK Development forum for you.

len0x
1st September 2005, 21:34
Its all simpler than that: 60% quality of divx6 is to match 75% quality of DivX 5.x (in terms of output size) since divx6 uses proportionally higher bitrate at the same quantizer level. This was already used in two pass mode since divx6 was supported in AutoGK, but to level defaults in single pass mode I just changed GUI (and only GUI) with default of 60%.

Codec settings are very usual apart from usage of "optimized h263" quantanization type.