naive question about volume rendering

[Heiko Gleitsmann]

Hi all,

does somebody knows if there´s a plugin available that works with RGB color.

Now I´m using the Volume Viewer plugin, but that plugin can't handle with
RGB color (and 8Bit color too).

THX...
--
regards
heiko

[Sergio Caballero]

One workaround is to split the RGB into separate channels, do the volume
rendering on each channel separately, and then use the RGB Grey Merge plugin
(http://rsb.info.nih.gov/ij/plugins/rgb-gray-merge.html) to merge them.

HTH

Sergio Caballero, Jr., MS
Pharmacology & Therapeutics
University of Florida
1600 SW Archer Road Rm R5-283 (shipping)
PO Box 100267 (mailing)
Gainesville, FL 32610-0267
O: 352-392-7958
F: 352-392-9696
M: 352-246-1429

-----Original Message-----
From: ImageJ Interest Group [mailto:[hidden email]] On Behalf Of Heiko
Gleitsmann
Sent: Tuesday, August 22, 2006 5:50 AM
To: [hidden email]
Subject: naive question about volume rendering

Hi all,

does somebody knows if there´s a plugin available that works with RGB color.

Now I´m using the Volume Viewer plugin, but that plugin can't handle with
RGB color (and 8Bit color too).

THX...
--
regards
heiko

[dscho]

Hi,

On Tue, 22 Aug 2006, Sergio Caballero wrote:

> One workaround is to split the RGB into separate channels, do the volume
> rendering on each channel separately, and then use the RGB Grey Merge plugin
> (http://rsb.info.nih.gov/ij/plugins/rgb-gray-merge.html) to merge them.

That would be not good.

Imagine a stack, where you have one red plane in front, and a green plane
in the back. RGB volume rendering would show the red plane, but your
method would show something orange in the middle (because in the
green-only volume rendering, nothing hid the green plane).

So, I think you'd have to enhance the volume rendering plugin to account
for RGB. Maybe it would be easier by using ImageJ3d:
http://www.f4.fhtw-berlin.de/~barthel/ImageJ/ImageJ3D/ImageJ3D.html

Hth,
Dscho

[ctrueden]

Hi,

Also, VisBio's volume rendering supports RGB color (
http://www.loci.wisc.edu/visbio/). Just adjust the opacity slider in the
color settings as usual (it affects all color channels) -- or you can
manually tweak the alpha channel of each channel's color table separately.

VisBio's algorithm for volume rendering (a series of semi-transparent
planes) is quite different than Volume Viewer's, so you'll probably get a
quite different picture (in some cases better, in some cases worse).

-Curtis

On 8/22/06, Johannes Schindelin <[hidden email]> wrote:

>
> Hi,
>
> On Tue, 22 Aug 2006, Sergio Caballero wrote:
>
> > One workaround is to split the RGB into separate channels, do the volume
> > rendering on each channel separately, and then use the RGB Grey Merge
> plugin
> > (http://rsb.info.nih.gov/ij/plugins/rgb-gray-merge.html) to merge them.
>
> That would be not good.
>
> Imagine a stack, where you have one red plane in front, and a green plane
> in the back. RGB volume rendering would show the red plane, but your
> method would show something orange in the middle (because in the
> green-only volume rendering, nothing hid the green plane).
>
> So, I think you'd have to enhance the volume rendering plugin to account
> for RGB. Maybe it would be easier by using ImageJ3d:
> http://www.f4.fhtw-berlin.de/~barthel/ImageJ/ImageJ3D/ImageJ3D.html
>
> Hth,
> Dscho
>