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Re: help with transparent plot in version 8.2.2 [message #83624 is a reply to message #83623]

Fri, 15 March 2013 14:03

chris_torrence@NOSPAM is currently offline

chris_torrence@NOSPAM
Messages: 528
Registered: March 2007

Senior Member

Hi Teddy,

I can explain this. In the docs for the TRANSPARENT keyword, there is a little-known sentence: "Set this keyword to an RGB value (a three-element vector of the form [R, G, B]) indicating which pixels in the output image should be made transparent. If this keyword is set to 1, the color of the lower left pixel in the image is used as the transparent color."

So, in your example with POSITION, you are putting the plot into the lower-left corner. So the pixel at [0,0] is actually black, which is unfortunately getting assigned as the transparent color!

The solution is to do p.Save, 'plot.png', TRANSPARENT=[255,255,255], which forces the transparent color to be white.

Hope this helps.

-Chris
ExelisVIS

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[Message index]

		Re: help with transparent plot in version 8.2.2 By: chris_torrence@NOSPAM on Fri, 15 March 2013 14:05
		Re: help with transparent plot in version 8.2.2 By: chris_torrence@NOSPAM on Fri, 15 March 2013 14:03
		Re: help with transparent plot in version 8.2.2 By: David Fanning on Thu, 14 March 2013 11:57
		Re: help with transparent plot in version 8.2.2 By: Teddy Allen on Thu, 14 March 2013 11:29
		Re: help with transparent plot in version 8.2.2 By: David Fanning on Thu, 14 March 2013 10:12
		Re: help with transparent plot in version 8.2.2 By: Teddy Allen on Thu, 14 March 2013 10:00
		Re: help with transparent plot in version 8.2.2 By: David Fanning on Thu, 14 March 2013 06:40
		Re: help with transparent plot in version 8.2.2 By: Brian Daniel on Thu, 14 March 2013 06:05

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