Convolution3D B4 or Aft Resize?

[gastorgrab]

I think maybe i'm using Convolution 3D incorrectly.

I've been using it after my resize assuming it would eliminate some of the remaining resize artifacts, but Black isn't quite Black anymore. I guess reducing the color range will increase compressibility though, files are smaller.

Is there a right and wrong way?

[jimmalenko]

I always use it before - I think I read somewhere that that was the best way to do it, and that the resize command should always be one of the last commands if using a script. I can't validate that with a source, just off the top of my head.

[FulciLives]

I always use Convolution3D prior to doing a RESIZE. I also like to use it before I do any croping.

- John "FulciLives" Coleman

[celtic_druid]

Better quality to use it before, faster to use it after (less pixels to filter).

No right or wrong way. Also there are other filters that you could try.

[gastorgrab]

From all the examples i could find online, most have Convo3d before the resize, but very few say why.

Time to experiment!

Thanks.

[FulciLives]

From all the examples i could find online, most have Convo3d before the resize, but very few say why.

Time to experiment!

Thanks.

I just realized you said that you were having a colorspace problem i.e., black not being really black in the end.

Sorry but I somehow managed to miss that the first time I read your first post here.

Give details as to how you capture and what capture codec you use and paste an actual AviSynth script that you are using.

Also tell us what encoder you are using.

- John "FulciLives" Coleman

P.S.
Take a look at my Convolution3D guide: CLICK HERE
I think the only change I would note (I guess I need to update the guide) is that if you need to use ConvertToRGB() you should really make it read ConvertToRGB24() and this applies with or without the added interlaced=true part.

[gastorgrab]

What i'm doing is using it to convert DVD to XviD for use on my DVP-642.

Script is simple; (Forced FILM from DGMPGDec)

LoadPlugin("C:\Ut\Video\DGMPGDec\DGDecode.dll")
LoadPlugin("C:\Program Files\AviSynth 2.5\YV12\Convolution3DYV12.dll")
#
mpeg2source("5thElement.d2v",cpu=6)# DGDecode Output is YV12
#
Lanczos4Resize(480,360).Crop(0,4,-0,-4)
#
Convolution3D(0,3,4,3,4,2.8,0)# movieHQ - DVD

Encoder is VirtualDubMod..............AVI is my destination.

DGDecode normally outputs YV12, and since i have no reason to alter it.......

I've been using Convolution3D with my DV conversions and got comfortable with it, so i figured, why not try it with DVD-Rip.

Here's my VDubMod template; (Look Familiar?)

#ASYNTHER DV to DVD
#
# LoadPlugin("ReInterpolate411.dll")
# LoadPlugin("Convolution3d.dll")
#
[AVISource("%f")]
# Put Trims Here
#
# ConvertToYUY2(interlaced=true)
ReInterpolate411()# Colorspace is YUY2
#
SeparateFields()
odd=SelectOdd.Convolution3D(1,6,10,6,8,2.8,0)
evn=SelectEven.Convolution3D(1,6,10,6,8,2.8,0)
Interleave(evn,odd)
Weave()# Bottom Field First (all even lines)
#
# DoubleWeave.SelectOdd()# Top Field First (all odd lines)
#
ConvertToRGB24(interlaced=true)# For TMPGEnc

There's no reason to use Reinterpolate with my DVD-Rips so i have to assume that color change is due to "Averaging Pixels".

Does this sound right?

[FulciLives]

What i'm doing is using it to convert DVD to XviD for use on my DVP-642.

Script is simple; (Forced FILM from DGMPGDec)

LoadPlugin("C:\Ut\Video\DGMPGDec\DGDecode.dll")
LoadPlugin("C:\Program Files\AviSynth 2.5\YV12\Convolution3DYV12.dll")
#
mpeg2source("5thElement.d2v",cpu=6)# DGDecode Output is YV12
#
Lanczos4Resize(480,360).Crop(0,4,-0,-4)
#
Convolution3D(0,3,4,3,4,2.8,0)# movieHQ - DVD

Encoder is VirtualDubMod..............AVI is my destination.

DGDecode normally outputs YV12, and since i have no reason to alter it.......

I've been using Convolution3D with my DV conversions and got comfortable with it, so i figured, why not try it with DVD-Rip.

Your script looks OK I guess although I'm not sure about the resize and crop values but I assume you know what you are doing there.

Might want to add this to the end of it:
ConvertToRGB24()
VirtualDub uses the RGB colorspace as far as I know but that might only be under VIDEO FULL PROCESSING and normally Xvid and DivX are done with VIDEO FAST RECOMPRESS in which case I think it stays YV12 but I'm not sure about that.

- John "FulciLives" Coleman

P.S.
I would put the Convolution3D part right after you load the D2V file ... in other words before you resize and crop.

What is the "cpu=6" option do ... I am not familiar with that.

[gastorgrab]

Might want to add this to the end of it:
ConvertToRGB24().

Sorry, i should have included this;



I'm using "Fast Recompress"

P.S.
I would put the Convolution3D part right after you load the D2V file ... in other words before you resize and crop.

Majority rules! I'm gonna try it this way on my next conversion.

What is the "cpu=6" option do ... I am not familiar with that.

It's specific to DGMPGDec, and is described in the document "DGDecode.html", included in the package ; DGMPGDec

Thanks!

[gastorgrab]

P.S.
I would put the Convolution3D part right after you load the D2V file ... in other words before you resize and crop.

Majority rules! I'm gonna try it this way on my next conversion.

Better yet, i'll try it both ways and do a direct comparison.

[FulciLives]

Are you using TV SCALE or PC SCALE in DVD2AVI or in this case DGMPGDec

Perhaps using one vs the other will make a difference. Not sure which is correct for making an MPEG-4

- John "FulciLives" Coleman

[gastorgrab]

Are you using TV SCALE or PC SCALE in DVD2AVI or in this case DGMPGDec

Perhaps using one vs the other will make a difference. Not sure which is correct for making an MPEG-4

- John "FulciLives" Coleman

I forgot about that setting!

I'll take a look.............It's set for PC scale, which is what i wanted anyway.

Doesn't "TV scale" = (8-235) range?

[FulciLives]

Are you using TV SCALE or PC SCALE in DVD2AVI or in this case DGMPGDec

Perhaps using one vs the other will make a difference. Not sure which is correct for making an MPEG-4

- John "FulciLives" Coleman

I forgot about that setting!

I'll take a look.............It's set for PC scale, which is what i wanted anyway.

Doesn't "TV scale" = (8-235) range?

Well TV SCALE should be 16-235 but that is what a DVD uses anyways so maybe that is the better choice?

I don't know much about how MPEG-4 handles things like colorspace and luminance etc. since I mostly do analog capture to DVD or PAL DVD to NTSC DVD.

- John "FulciLives" Coleman

[gastorgrab]

Here's the difference between PC-Scale, and TV-Scale;



It looks like what i expected to see.

It also looks just like the problem i was having. It didn't show up till i used Convolution3d.