ModifyImage Transparency flag

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Hi,

I am working with images and need to create some false color maps to overlay the base image.

What would be really useful would be within the modifyimage command to be able to set a color table and an overall transparency for that image.

For example: I can set an image to yellowhot but I would also like to be able to set the alpha to 0.35 (35%) for example.  There are workarounds to create color waves and then add an alpha channel,...

Additionally if the value can be incorporated via a control in the dialog panel, that would be extra nice.

Andy

You can use a color table wave, which can be a 4-column wave. Use ColorTab2Wave to fill a wave with your chosen color table, and then set the fourth column to whatever alpha you want:

ModifyImage junk2 ctab= {*,*,MyColorWave,0}

Where "junk2" is my image wave, and "MyColorWave" is the name of my color table wave. You can use the Color Wave Editor package (Data->Packages->Color Wave Editor) to create and fill the wave with whatever colors you wish.

March 21, 2023 at 09:23 am - Permalink

That is what I have been doing and the request is to take some of the steps out.

What I am asking is something similar to what is in the image threshold dialog panel.

Where there is a see through threshold check box and an alpha level set variable control.  Sort of combining both.

I would not have to create additional waves and the associated steps.  That is why it is on the wish list.

Andy

March 21, 2023 at 09:58 am - Permalink