Color space of the image camera generated by isaac sim Replicator Composer

Omniverse Isaac Sim
1

Hi there,

I am generating training data using isaac sim Replicator Composer. In my experiment, I need to blur the image in the raw RGB linear space. I want to know the color space of default camera images generated by isaac sim, that is, what post-processing they go through (did they have gamma coding?), or isaac sim just give me the raw RGB data. How can I check it? Thanks.

3

Hi @linwk20 - Isaac Sim uses the Omniverse Kit, which by default applies a gamma correction of 2.2 to the final rendered images. This means that the images you get from the camera are in sRGB space, not linear RGB space.

If you want to get raw linear RGB data, you need to disable the gamma correction. You can do this by setting the colorTransform attribute of the camera to Linear:

camera_prim.GetAttribute('colorTransform').Set('Linear')

After setting this attribute, the camera will output raw linear RGB data.

Please note that this will affect all subsequent images taken with this camera. If you want to switch back to sRGB space, you can set the colorTransform attribute back to sRGB:

camera_prim.GetAttribute('colorTransform').Set('sRGB')

You can check the current color space of the camera by getting the value of the colorTransform attribute:

color_space = camera_prim.GetAttribute('colorTransform').Get()
print(color_space)

This will print either Linear or sRGB, depending on the current color space of the camera.