8 bit png with alpha (8 bits) mask

[CheloXL]

Hi,

It seems that XnView does not correctly supports 8 bit png (256 colors) with 8 bits mask? If I open the png in XnView, I see the image rendered without the mask and it is not possible to extract the mask, nor convert the file to any other format and retain the transparency.

The file was created with PNGOut and renders fine on any browser (that supports transparent png, of course).

It is possible for XnView to implement this feature? Maybe not writing, but at least reading...

Thanks in advance and regards,

[Clo]

CheloXL

Hello ! Welcome aboard !

• That works here : Image Menu >> Edit palette >> Tick the box
and click the cell of the BG colour you want as the transparency…

Kind Regards,
Claude
Clo

[CheloXL]

That's not what I wanted. That creates an 8 bit png with 1 bit alpha mask - same as a GIF file. I'm talking about an 8 bit png with 8 bit alpha mask. It's like a 32 bits png (RGBA - 24.7millon colors + 256 grayscale mask), but instead of having 24bits for color, you have an indexed palette PLUS the alpha (256 levels of transparency).

Also, I would like XnView to display/convert the png correctly, not the ability to create this kind of png.

[xnview]

Currently 8bits image + 8bits alpha is not supported

[CheloXL]

Hi Pierre,

Thanks. Do you have plans on supporting it?

Regards,

[xnview]

Thanks. Do you have plans on supporting it?

Yes, but as low level

[MaxSt]

Yeah, I noticed that too (see example below), but full PNG support is obviously (and sadly) not a high priority for XnView.
I like XnView, so it's sad to see it lagging behind even Internet Exprorer, with regard to PNG transparencies.