Extracting alpha channel from grey scale PNG

[ckv]

I'm trying to extract the alpha channel from a grey scale PNG file without any luck. When I use the extract alpha channel option on XnView MP nothing seems to happen and on XnView the option to extract the alpha channel is grayed out. Converting to 32-bits first doesn't work either, on XnView MP I just get a white image with white mask. What gives?

[XnTriq]

Hi ckv (-:

This is a limitation known from XnView Classic.

• PNG with transparency not showing
• PNG transparency problem
• 256-color png displayed in grayscale
• Incorrect display of a png image
• Alpha channel is ignored for grayscale PNG
• Wish: extract mask channel of PNG
• 8 bit png with alpha (8 bits) mask
• Partial Transparence in GFL_COLORS and GFL_GREY

• GFL can't decode png
• Editing an images loses its transparency

[ckv]

Hi ckv (-:

This is a limitation known from XnView Classic.

...

Thanks, helpful as always

I finally got the mask from my image by using IrfanView which seem to handle these files a little better than XnView.