0.97.1: Embedded color profiles in 16bpc png files are ignored
Posted: Sun Nov 22, 2020 4:27 pm
XnView: 0.97.1 64bits (Oct 13 2020)
OS: Windows 10 64bit
Embedded color profiles are ignored when 16 bit per channel png images are loaded, even with ICC settings enabled. This bug doesn't seem to happen for 8 bpc pngs or for 16 bpc files in other formats like psd or tif.
Effect: 16 bpc pngs are displayed with the wrong colors.
This is especially important because recent versions of iOS (maybe Android too?) now save screenshots as 16 bpc pngs with the Display P3 color profile by default, which means lots of images will not display the correct colors in XnView.
To reproduce:
1. Enable ICC color profile settings in XnView.
2. Download the photograph (jpg) of the car from this site: https://petapixel.com/2012/06/25/is-you ... r-managed/
If embedded color profiles are correctly enabled, the car will appear orange. If not, it will appear purple.
3. Open the image in an image editor such as Photoshop, preserving the embedded profile as the working color space.
4. Convert the image to 16 bits per channel. (Photoshop CS6: Image menu>Mode>16 Bits/Channel)
5. Save the image as a png, preserving the color profile.
6. Open the new png in XnView.
(I apologise for not providing a sample image directly, but the above image uses a custom color profile that readily highlights the issue.)
Actual behaviour: XnView fails to apply the embedded color profile and the car appears purple.
Expected behaviour: XnView correctly applies the embedded color profile and the car appears orange.
OS: Windows 10 64bit
Embedded color profiles are ignored when 16 bit per channel png images are loaded, even with ICC settings enabled. This bug doesn't seem to happen for 8 bpc pngs or for 16 bpc files in other formats like psd or tif.
Effect: 16 bpc pngs are displayed with the wrong colors.
This is especially important because recent versions of iOS (maybe Android too?) now save screenshots as 16 bpc pngs with the Display P3 color profile by default, which means lots of images will not display the correct colors in XnView.
To reproduce:
1. Enable ICC color profile settings in XnView.
2. Download the photograph (jpg) of the car from this site: https://petapixel.com/2012/06/25/is-you ... r-managed/
If embedded color profiles are correctly enabled, the car will appear orange. If not, it will appear purple.
3. Open the image in an image editor such as Photoshop, preserving the embedded profile as the working color space.
4. Convert the image to 16 bits per channel. (Photoshop CS6: Image menu>Mode>16 Bits/Channel)
5. Save the image as a png, preserving the color profile.
6. Open the new png in XnView.
(I apologise for not providing a sample image directly, but the above image uses a custom color profile that readily highlights the issue.)
Actual behaviour: XnView fails to apply the embedded color profile and the car appears purple.
Expected behaviour: XnView correctly applies the embedded color profile and the car appears orange.
Thanks to your detailed description I can reproduce