How to load linear EXR images?

[mcg222]

To import images for colour-checker-detection, I use:

COLOUR_CHECKER_IMAGE_PATHS = glob.glob(
os.path.join('/content/', '*.png'))

COLOUR_CHECKER_IMAGES = [
colour.cctf_decoding(colour.io.read_image(path),function="REDLog")
for path in COLOUR_CHECKER_IMAGE_PATHS
]

for image in COLOUR_CHECKER_IMAGES:
colour.plotting.plot_image(colour.cctf_encoding(image));

I'd like to be able to import linear EXR images. How can I do that? I enabled the OpenCV option to allow for EXR images, but when I bring them in they show up as black. Is there some kind of pass through option so that images aren't linearized?

Thanks!

[KelSolaar]

Hi @mcg222,

You will need to load the freeimage backend to have EXR read and write support. This is how we typically do that:

python -c "import imageio;imageio.plugins.freeimage.download()"

[mcg222]

Thanks! Now the EXR images open! The next thing I need to do is to bypass the encoding to linear and decoding to sRGB in:

COLOUR_CHECKER_IMAGES = [
colour.cctf_decoding(colour.io.read_image(path),function="Log3G10")
for path in COLOUR_CHECKER_IMAGE_PATHS
]

for image in COLOUR_CHECKER_IMAGES:
colour.plotting.plot_image(colour.cctf_encoding(image));

As it is taking my already linear EXR image, and attempting to linearize it. With the above it thinks its Log3G10. How can I tell it it's already linear? Thanks!

[KelSolaar]

If your images are already in a linear state this should be enough:

COLOUR_CHECKER_IMAGES = [
    colour.io.read_image(path) for path in COLOUR_CHECKER_IMAGE_PATHS
]

[mcg222]

@KelSolaar Thanks so much. That worked perfectly!