Alpha-mask vs. merged-Transparency in PSD format

[Guest]

Hi,

I'm trying to read merged RGBA data from PSD format. "Image data" section contains channels (RGBAA... where first A might be a merged transparency or Alpha mask). Can someone tell me how to know what is stored in first A? I noticed that:

• when image contains no transparency, but has at least one Alpha mask, then first Alpha channel will contain that alpha mask
• when image contains transparency, then first Alpha channel will contain merged transparency and other Alpha channels will contain alpha masks

So how do I reliably differentiate between Transparency and Alpha mask in first Alpha channel?

Regards,

Paulius Liekis

Unity Technologies

[John T Smith]

This forum is to discuss the forums, not products

You need to ask your question in the forum for the Adobe product you are using

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[Chris Cox]

All of that is well documented in the PSD format docs in the Photoshop SDK.

[PECourtejoie]

And here is a link to the Photoshop SDK: http://www.adobe.com/devnet/photoshop/sdk.html