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Re: Increment option missing in "AVI..." read and "Z Project..." write macros

Posted by Alan Hewat on Aug 18, 2009; 3:46am
URL: http://imagej.273.s1.nabble.com/Increment-option-missing-in-AVI-read-and-Z-Project-write-macros-tp3691458p3691459.html

It took me a while, but searching the archives :-) I came across the
Image>Stacks>Reduce Size command that existed in ImageJ 1.42, but has
since been removed from the standard distribution :-(

I have re-installed it from
http://rsb.info.nih.gov/ij/plugins/stack-reducer.html and it is
perfect for my purposes eg

run("AVI...", "select=D:\\temp\\vdub.avi first=1 last=500");
run("Reduce Size...", "reduction=10");

I can't see how to do that in standard v1.43  with ImageJ>Adjust Size
or ImageJ>Scale

Wayne wrote 2 June:
> The Image>Adjust Size and Image>Scale commands in v1.43
> will be able to scale in the z dimension.

BTW I found the archives at http://n2.nabble.com/ImageJ-f588099.html
easier to use than those at https://list.nih.gov/archives/imagej.html

2009/8/17 Alan Hewat <[hidden email]>:

> Creating a stack using "Image Sequence..." has the useful "Increment"
> option that imports only every Nth image.
>
> Creating a stack using "AVI..." does NOT have this "Increment" option,
> but only accepts the First and Last Frame to import.
>
> After importing the avi I want to sum the frames using "Z Project...",
> which also doesn't have an Increment option :-)
>
> So how can I open an avi file and sum every Nth frame ?
>
> Explanation: my camera's PAL output is captured as an avi file at 25
> fps using Vdub, but since the camera integrates N frames internally,
> only every Nth frame is different. This is not a problem if I output
> the "Average Intensity" with "Z Project..." to create an 8-bit
> average, but I would like also to "Sum Slices" to create a 32-bit sum.
> If there are lots of duplicate frames, the sum can overflow the
> resulting 32-bit TIF file. Yes, I could average every N-frames, create
> a new stack, and then sum these averages, but that seems rather
> inelegant :-)
>
> Alan.
> ______________________________________________
> Dr Alan Hewat, NeutronOptics, Grenoble, FRANCE
> <[hidden email]> +33.476.98.41.68
>        http://www.NeutronOptics.com/hewat
> ______________________________________________
>



--
______________________________________________
Dr Alan Hewat, NeutronOptics, Grenoble, FRANCE
<[hidden email]> +33.476.98.41.68
        http://www.NeutronOptics.com/hewat
______________________________________________