Compose Image with alpha

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Ithier
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Compose Image with alpha

Post by Ithier »

Hi,

I have a 32 bits png image. When I load it and save it in PNG all is fine, the transparency is kept. When I load it and save it in JPEG, the image is mainly black (transparency become black).
When I load this PNG image in XNview it is also black except when I use the
"Compose Image with alpha" option in Options->Read-PNG, then the image is on a white background.

So my question is, what is this option and how can I do the same with the GFL SDK.

Thanks in advance.
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xnview
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Re: Compose Image with alpha

Post by xnview »

Ithier wrote:Hi,

I have a 32 bits png image. When I load it and save it in PNG all is fine, the transparency is kept. When I load it and save it in JPEG, the image is mainly black (transparency become black).
When I load this PNG image in XNview it is also black except when I use the
"Compose Image with alpha" option in Options->Read-PNG, then the image is on a white background.

So my question is, what is this option and how can I do the same with the GFL SDK.
JPEG don't support 32bits, only 24bits. So i'll add an option like XnView...
Pierre.
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Ithier
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Post by Ithier »

Hi Pierre,

Will you include this option in the next version of the SDK. It would be great.

Have a good week-end.

Ithier
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Ithier
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Post by Ithier »

Hi Pierre,

This problem becomes rather annoying to me. When do you plan to release a new Gfl Sdk version and will it include this option: Compose with Alpha (as it exists in the Read/Png parameters of XnView).

Thanks in advance.

Ithier
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Ithier
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Post by Ithier »

Sorry Pierre,

I didn't remember that you already implemented it. It works perfectly.
Thanks.

Ithier
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