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Support RGBA images with proper color tables #178

ctrueden opened this issue May 9, 2014 · 1 comment


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commented May 9, 2014

When opening RGBA images, or other images with an alpha channel, we can represent that with the current SCIFIO API—we just need to do a little additional processing.

Each "red" plane will have an associated ColorTable8 with four elements instead of three, with the first element being the red values and the fourth element being the alpha. Similarly, "green" planes will populate a ColorTable8 using the 2nd and 4th elements, and the "blue" planes will populate one which sets the 3rd and 4th elements. The 4th elements will be the same across all three channels. In this way, each component will preserve alpha information, and we can composite the three channels' color tables together as needed (as long as alpha values are averaged instead of added, which may not be the case currently, but which we can fix).


@ctrueden ctrueden changed the title These images don't look right Support RGBA images with proper color tables May 9, 2014


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commented May 9, 2014

It will then be the responsibility of ImageJ and other viewers to deal with the color tables that SCIFIO gives back in the case of an alpha channel being present.

@hinerm hinerm added the enhancement label Mar 11, 2015

@hinerm hinerm added this to the 1.0.0 - Official Release milestone Mar 11, 2015

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