Resize Filters?

[blomp]

can someone give me a better explanation of resize filters? i get the impression that they effect the level of contrast in frames, is sharp bicubic always the best setting to use?

[UHT]

From the upcoming Gordian Knot Q&A (FAQ)

Q: Can I change the resizing method that Gordian Knot sets ? What is the difference between bilinear, soft bicubic, neutral bicubic and sharp bicubic resizing ?

A: Yes you can change the resizing method Gordian Knot uses. Bilinear resize compresses better than all the others but edges on objects in the film are fuzzier. Sharp bicubic resize has sharp edges but does not compress as well but obviously looks better. The other two settings are in between these two extremes. Keep in mind that Gordian Knot will usually choose an appropriate resize method so it may not be wise to make a change from a bilinear setting all the way to sharp bicubic for example.

As a rule of thumb, maximum filesize with sharp bicubic will be 30-40% higher than with bilinear, the others lie in between... meaning for e.g. if you get a comp-check-perc of 50% with sharp bicubic you might reach about 65% with bilinear. The picture will be more blurred but the codec macroblocks will be less visible.

[blomp]

i should have checked the literature first i spose :o

thanx for that UHT.

as a rule of thumb, what is a good resize filter setting for a 2cd movie of say 1500kbit/s videostream?

[UHT]

sounds like sharp bicubic is the order of the day, although depending on the scene content of the film it could look a little pixelated using this filter. i pretty much always use sharp for my 2cd rips, unless its like a 3hour film

[blomp]

sounds good, thanx for that :)