1. Select the image.
  2. Choose Add visibility mask from the Image menu.


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  3. Double-click on the Wand tool in the Paint tools palette and uncheck select throughout image and use a low value for tolerance.


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  4. Click on the white background areas of the image. You shall see the white area being selected.


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  5. Hit the Delete key to erase the white area.


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Note : You probably can not see the result as the background of the Canvas is white by default. Move the image to the paste board (gray area) to verify the transparency result.



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If the background is made of different colors, you will have to use the lasso tool to select the unwanted pixels and then delete them.