Alpha Channel Rotation

We are having an issue when Photoshop files are downloaded using a Targa Derivative where the alpha channel is being inverted. This only appears when the Targa file is opened in ProSpace. If you open, save, and close the Targa file, the alpha channel is then correctly viewed in ProSpace.
We are having an issue when Photoshop files are downloaded using a Targa 32-bit Derivative where the alpha channel is being rotated 180 degrees. This only appears when the Targa file is linked and displayed in JDA's ProSpace (a retail display management program). If you open and close the Targa file in Photoshop (don't need to re-save the file to fix) , the alpha channel is then correctly viewed in ProSpace.

We have done some investigation and we suspect that the problem is in Targa's offset# 17, length 1, description: image descriptor byte. Bit 5 is the screen origin bit:
0 = origin in lower left hand corner
1 = origin in upper left hand corner
It must be 0 for Truevision images.

This display anomaly has been reported by ameteur astronomers when using the Targa file format for images captured with astro-imaging CCDs.
I have a powerpoint which outlines this issue and can provide it if would like a visual. If you look at it, you can see that the alpha channel is distorting the "silhouette" of the image.

Can anyone provide some insight into this and possibly a solution? Can we modify the download task?

Thank you.

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Comments

lyman

Greetings. I am aware that Targe supports multiple orientations (there is even a very little-used format that flips the image let to right!). It sounds as if we missed a combination! Please open a support case and they can get the test files to engineering, and we will get this sorted out.

Thanks,

Lyman Hurd
MediaBin Server Team

MediaBin Server Team
Interwoven, Inc.