Posted by
Michael Schell on
Apr 07, 2008; 7:14pm
URL: http://imagej.273.s1.nabble.com/detect-motion-across-frames-tp3696278p3696293.html
You might try plugins-stacks-TFunctions-deltaFdown. This will
compare two stacks in succession, subtract pixel-by-pixel, and store
the difference. Thus, it makes a new stack that consists of pixels
that changed intensity over time. If you flatten this stack as a
maximal projection, you can see regions that showed the greatest
movement (although often the vectorial info is lost). The average
pixel intensity of the flattened stack can sometimes be assigned an
arbitrary value as a "motility index."
We used this successfully to measure changes in mitochondrial
motility caused by intracellular calcium (ref below), but it might
work for clouds too:
Brough D Biochemical J. 392:291 (2005).
Michael
On Apr 7, 2008, at 2:38 PM, Brian Willkie wrote:
> Hello,
>
> I searched the list archives briefly, but didn't find this topic
> specifically. It's entirely possible that I simply didn't know what to
> look for.
>
> I have access to GOES 12 satellite data (i.e. cloud data) as either
> raw data, TIFF files - frame by frame - or High definition QuickTime
> movie.
>
> I'd like to use some image-processing techniques to identify pixels
> that you and I would group togther as a clouds, and track their motion
> from one frame to the next.
>
> Analyze particles seems to work well to identify clouds in a given
> frame. Are there any commands / plug-ins / algorithms to track their
> motion/change across frames (i.e. can I get a dataset that tells me
> that a given particle in the current frame is the same particle as one
> found in the previous frame, although its size, shape, and/or position
> have changed slightly)?
>
> Thanks,
> Brian
Michael J. Schell, Ph.D., CIV, USUHS
Assist. Professor
Dept. of Pharmacology
Uniformed Services University
4301 Jones Bridge Rd.
Bethesda, MD 20814-3220
tel: (301) 295-3249
[hidden email]