Re: ROI selection in line scan pictures

Posted by Wayne Rasband on Oct 04, 2007; 4:45pm
URL: http://imagej.273.s1.nabble.com/ROI-selection-in-line-scan-pictures-tp3698271p3698275.html

Press "a" (Edit>Selection>Select All) to create a rectangular selection
encompassing the entire image. Press alt-k (Analyze>Plot Profile with
alt key down) to plot the average intensities of the lines. Click on
"List" in the plot window to display the intensity values. The Plot
Profile command plots column averages instead of row averages if you
don't hold the alt key down.

-wayne

On Oct 4, 2007, at 11:09 AM, Alexandre Santos wrote:

> Hello,
>
> I would like to analyze some confocal line scan pictures I acquired in
> two channels. Each channel (called z slice in imagej) is a picture of
> 512 pixels width and 50,000 pixels height
>
> I would like to be able to select a segment of the line scan, and
> obtain average intensity levels for each line of the scan, in both
> channels.
>
> At the moment I have two difficulties:
>
> 1 - I can't find a way to select a segment as a ROI. If I want to see
> the picture, I need to magnify it a lot, but then I can't draw a
> rectangle encompassing the whole picture.
>
> 2 - Once I have the desired rectangle, How do I get average intensity
> values for each line of the rectangle, and not for the whole
> rectangle? (I thought about using the Gel analysis tool, but I don't
> know if that would work)
>
> Cheers,
>
> Alexandre Santos
> Neuro-MPI, Martinsried, Germany
>