Incorrect description of 16 bit PNG image files..

[john3774]

I have a monochrome image file with 16 bit image depth. At least, Matlab and Windows Explorer say it is 16 bit.

The preview box of XYPlorer Ver. 16.30 says it is "16M ARGB (32-bit) ".
Running on Windows 7 Pro, SP1, 64 bit OS.

Any ideas as to why the discrepancy?

Best regards,
John

[admin]

Could you send me the pic?

[john3774]

Hi -
Sorry for the belated reply. I thought I would get a notice when someone replied, obviously that didn't happen. 3 files attached.

The effect is the same for both 8 bit and 16 bit images, I attached both.

Best regards,
John

[admin]

Confirmed on Win8.1 with XY 17.50.

That's really weird. The last time I tested this was under XP I think and the code worked 100% with all pixel formats (I have all sorts of PNG test files here). But now many of them (but not all) return "16M ARGB (32-bit)". Hard to see a pattern. Looks like a GDI bug. To fix this I would have to work out a programmatic way to calculate the pixel format natively. Interesting task but it will probably take a while and I can't start it right now.