Re: 32bit colocalization plugin

Posted by Colin Rickman on Nov 04, 2008; 12:29pm
URL: http://imagej.273.s1.nabble.com/32bit-colocalization-plugin-tp3694593p3694595.html

Hi Tony,

Thanks for getting back to me. I'm not after the threshold values. I use
the values for the gradient (m) and y-intercept (b) given by the plugin
to calculate the residual for each pixel in the image (which I then
colour code).  The calculations for this all use 32 bit float (to permit
both negative and non-integer values). I am trying to avoid converting
from 32bit (the data currently contains non-integer values) to signed
integer to use the plugin but then calculating the residuals back in
32bit float.

If there is an alternative plugin which can provide the gradient,
y-intercept and Pearsons correlation coefficient using two 32bit float
3D stacks that would be great.

Colin

Tony Collins wrote:

> Hi Colin,
>
> May be tricky. The original algorithm steps through the data setting a threshold at "intensity/2" until it finds one where the Pearson's value is zero. With a 32-bit image this would require too many steps!
>
> I'm also not sure 32-bit would give you much more information. Pearson's coefficient normalises the data anyway so you may want to scale it to 16-bits.
>
> Hope this helps,
>
> Tony
>
> -----Original Message-----
> From: ImageJ Interest Group [mailto:[hidden email]] On Behalf Of Colin Rickman
> Sent: November-03-08 6:17 AM
> To: [hidden email]
> Subject: 32bit colocalization plugin
>
> Hi,
>
> I currently use the colocalization threshold plugin to calculate the
> linear regression between two channels. At present this plugin can only
> use 8bit or 16bit unsigned byte images. Is it possible to change the
> plugin to accept 32bit float images or is there another plugin out there
> which can do this.
>
> Hoe you can help
>
> Colin
>
> --
> Dr Colin Rickman
> Centre for Integrative Physiology
> School of Biomedical Sciences
> University of Edinburgh
> Hugh Robson Building
> George Square
> Edinburgh
> EH8 9XD
>
> Tel: [phone]
> Fax: [phone]
>
>
> The University of Edinburgh is a charitable body, registered in
> Scotland, with registration number SC005336.
>
>  

--
Dr Colin Rickman
Centre for Integrative Physiology
School of Biomedical Sciences
University of Edinburgh
Hugh Robson Building
George Square
Edinburgh
EH8 9XD

Tel: [phone]
Fax: [phone]


The University of Edinburgh is a charitable body, registered in
Scotland, with registration number SC005336.