Bilinear , Bicubic or Precise Bicubic

[LSchafroth]

I've doen a few searches on the web and here and have three different opinions.

I am using VirtualdubMod to resize, crop and frameserver to TMPGEnc. Since BT878 cards kick in a resizer filter below 360 resolution I capture at 368x480. I then resize to 344x480, then add to it making it 352x480.

This has been working great. I just wanted to confirm which would be the best for quality in my situation? I've seen people say Bicubic is only for enlarging. Bilinear is for reducing. On here I've read the complete opposite.

Which setting in VDMod would be the best for my usage?

Thanks!

LS

[LSchafroth]

I did some testing of my own and found different results then other guides show.

The other guides state that Bilinear will give a softer look and better compression. I compared Precise Bilinear, Precise Bicubic -0.60 and Precise Bicubic -0.75.

All three looks identical. -0.60 gave the best compression. Bilinear gave the worst compression. I think my reduction is so minor that I cannot see the difference in the three. I'm going with -0.60 Bicubic and so far the results are identical to the original tape.

Thanks!

LS

[Suntan]

Personally, I believe in getting the sharpest resize possible then softening as needed (vs using bilinear to do both.) The downside is longer encoding time.

For my iPAQ encodes I prefer to resize down with Lanczos then add Undot and Temporalcleaner (for compressability) if the source is a clean DVD, if it is not clean I will look at other filters depending on the problem. I use AVIsynth for this, but Vdub's temporal filter is pretty good too.

-Suntan

[BJ_M]

see here for an explaination of the resize filters

https://www.videohelp.com/forum/viewtopic.php?t=238215&highlight=

[LSchafroth]

see here for an explaination of the resize filters

ttp://www.videohelp.com/forum/viewtopic.php?t=238215&highlight=

Link doesn't work.

Thanks!

LS

[Cornucopia]

Typo:

not-- ttp://www.videohelp.com/forum/viewtopic.php?t=238215&highlight=

but,

https://www.videohelp.com/forum/viewtopic.php?t=238215&highlight=

[LSchafroth]

Typo:

not-- ttp://www.videohelp.com/forum/viewtopic.php?t=238215&highlight=

but,

https://www.videohelp.com/forum/viewtopic.php?t=238215&highlight=

Good lord I should have noticed the ttp part. Sorry.

I've actually already read that topic before. So far Precise Bicubic -.60 is workign very nicely. I will experiemnt with the temporal filter tonight, time permitting. (If Green Bay chokes again, I will have plenty of time to use the computer instead of watch TV) hehe

LS

[Suntan]

@LSchafroth

So how were compairisions, obviously you had plenty of time to use the computer... 8)

-Suntan

[BJ_M]

Bilinear and Bicubic both look like crap to me , they also will cause a slight color shift in some apps

[LSchafroth]

@LSchafroth

So how were compairisions, obviously you had plenty of time to use the computer... 8)

-Suntan

I watched two series of the Packers, then shut it off. I used the temporal filter, 2d, and the Flaxen filter and I can see no noticeable difference between any of them. I found a guide on how to use the Flaxen filter. since my source is pretty clean, I'm only using the stabilizer portion of the filter as the noise reduction doesn't produce anything noticable and really slows down the incode.

I noticed teh Flaxen filter cleans up the color a touch and some of the grain in the video is gone. It sure is slow though....

LS

[Suntan]

@LSchafroth

Yeah, Vdubs filters do little for clean sources. The Temporalcleaner AVIsynth filter is both a temporal and spatial filter so it visibly softens the image. I would agree that for a clean DVD source I prefer little to no filtering (Also, I don't resize those just crop the blacks) but for my IPAQ encodes temporalcleaner helps a lot with compressability (for reference I much prefer soft images to macroblocks).

-Suntan