Photoshop: PNG Alpha Interpretation

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After Effects has very useful option when you load the file, in terms of alpha interpretation, depending on which color file was rendered, guess, straight alpha or ignore alpha. Now Photoshop just cut the image with internal alpha. Just example, now if I need PNG with preserved information I need to open in AE then render with no alpha.

Thanks,
Eduard
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Eduard Zhikharev

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Posted 3 years ago

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Chris Cox

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The PNG spec defines the fourth channel as transparency in completely unambiguous terms. It should never be treated as an unassociated alpha channel.

The PNG spec also defines the color channels to be unmatted/straight color when a transparency channel is present.

Photoshop is treating the fourth channel in PNG exactly how the PNG spec. says it should - as transparency, and the color data not premultiplied.

If someone is writing unassociated alpha channel data, or premultiplied color data, into a PNG image, then they are violating the PNG spec. and need to fix their code.
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Eduard Zhikharev

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Sounds everything reasonable, but I am working with PNG already more then 10 years, and I think PS only one app that doesn't have this option, and seems like all other leader app in industry violating the PNG spec. even colleagues from AE.

What the point of this answer, I just asking things that will help make work faster.

But anyway thank you for respond.