VDub's Lanczos3 or DivX's Lanczos4 ?

[crnagora]

Hi @all,

as the topic says I would like you're opinion on this one and Resize Filters in general.

I've done some tests, and it seems that the Lanczos4 Filter in DivX (Not the "fast" one) leads to a blurrier pic compared the Lanczos3 Filter in VDub.

Shouldn't Lanczos4 be superior ? Could it be that the DivX Implementation of the Filter is buggy ?

My goal is to Resize HDTV-Material to 640 x XXX and to have the sharpest picture possible. Are there any alternatives to Lanczos/Bicubic ?

Thanks for your opinions.

[Awatef]

You probably don't want to use DivX filters at all in the first place. My few tests with them were very unsatisfactory.

Lanczos is more than enough for downsizing, and keep in my mind that you're resizing from an HD source with superior detail level that you'll never achieve on 640x resolution! So don't compare both, if you do, you'll never be satisfied.

[Mary H]

This brings a question to my mind... If you're converting an HD file to DivX, how do you specify whether the DivX filter will be used, or the VirtualDub filter? I seem to have to set both in order to get the size I want. Which is actually doing the resizing?

[Blue_MiSfit]

Use AviSynth. Chances are you are already using it to get video into VirtualDub in the first place.

Just add :
lanczosresize(x,y) or lanczos4resize(x,y) to the end of your script.


~MiSfit

[Mary H]

Use AviSynth. Chances are you are already using it to get video into VirtualDub in the first place.

Just add :
lanczosresize(x,y) or lanczos4resize(x,y) to the end of your script.


~MiSfit

If you're answering me, no I actually use VirtualdubMod, never messed with AVISynth.

EDITED TO ADD: I just did some testing, and I see now how to use either the VDModResize filter or the DivX resizing function, but not both.

I've just recently been trying Dr. DivX too... I see it has it's own 'drffmpeg' filter, as well as Lanzcos, etc. How does that resize filter compare?

[Blue_MiSfit]

So you just drag and drop MPEG-2 onto VirtualDubMod?

Give AviSynth + DGIndex a try. One of its greatest strengths is in knowing EXACTLY what is happening to your video every step of the way. Just install AviSynth and DGIndex. Read a tutorial on how to make a D2V, and then write a simple script:


loadplugin("...\dgdecode.dll")

mpeg2source("...\your video.d2v")
lanczosresize(x,y) # or lanczos4resuze(x,y)


AviSynth also makes it really simple to add a bit of filtering. Say that HD is noisy, you can do a gentle denoise (probably before resizing), and even sharpen it a bit (also before resizing).

Do it how you want, regardless, but there are a lot of advantages to working with AviSynth :)

~MiSfit

[Awatef]

You have to like programming to like avisynth though :D

[chilledoutuk]

i hate programming but I love avisynth

[Awatef]

@ chille...
Wasn't ment to be serious... just pointed out that it smells like programming ;)