Re: Problem with scaling stacks

Posted by Rasband, Wayne (NIH/NIMH) [E] on
URL: http://imagej.273.s1.nabble.com/Problem-with-scaling-stacks-tp5017397p5017413.html

> On Oct 14, 2016, at 2:56 PM, Paletzki, Ron (NIH/NIMH) [C] <[hidden email]> wrote:
>
> I have been trying to scale a stack of images and have been getting some weird results and I wonder if this is a known bug or some other problem.  I have a stack of size 1086x 782y 1242z pixels  32-bit gray (same results for 16bit and 8bit images).  When I use the scale function from the menu “Image:Scale…"  in the dialog box I set the x y and z scaling to the same value and then the dialog box shows the correct expected changes in X Y and Z scale.  But when it actually performs the scale the Z axis is incorrect for scale values from 0.4 to 0.1, but works correctly for values from  0.9 to 0.5.  The X and Y are always correct.  
>
> For example:
> scale 0.1 I get 125 slices when I should get 124,
> scale 0.2 I get 249 slices when I should get 248
> scale 0.3 I get 414 slices when I should get 372
> scale 0.4 I get 621 slices when I should get 496
>
> I’m running Fiji / ImageJ version 2.0.0-rc-43/1.51g build 49b667f9aa on a Mac OS 10.8.5
> The Scale dialog box is set to Interpolation:None, Average Downsizing, Process entire stack and Create new window.

The latest daily build (1.51h8) fixes a bug that caused the Image>Scale and Image>Adjust>Size commands to not work as expected with z scale factors less than 0.5 when Interpolation was set to None.

-wayne

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