Radiance fish eye view background

Hello All,

Is it possible to have a white background(Typically, it’s black) in a fisheye view HDR that is generated when using the image based recipe? or is it something that has to be post-processed in Photoshop only?

Thank you!

I don’t know the answer to this question and if it is possible but even if possible it will be confusing to set the color to white. The colors are representing luminance values and the black color represents 0 which is the correct color.

Hi @mostapha,

I am mainly working towards implementing something similar to this. While we already know the radiance utility that adds text to the image and we are using it too in Honeybee_Glare Analysis component, I am not sure if there’s a utility or a parameter in that sets the background color white.

Hi @devang, I see what are you trying to do. You should be able to use pcomb in radiance to replace all the black pixels out or the circle with white.

Since we know the radius of the image ( = width / 2) we can calculate the position of all the pixels which are out of the interior circle. If we consider the center of the image as 0, 0 then any pixel that sqrt(x^2 + y^2) is larger than the radius is out of the circle and can be replaced by white.

The question is does it really help?

White in Radiance renderings corresponds to equal energy white and messing around with that can cause unexpected results and/or confusion. In that DIVA, GIF/video they are using the default falsecolor palette. Falsecolor has 2 other palettes that you can use as well.

Do you mean that false-color removes the black color by default?

Yes Mr. I-Love-D3.js, under the default scale, 0 is mapped to purple. So, black becomes purple.

I take this as a compliment :smile:

Based on my understanding from what @devang is trying to achieve falsecolor is not going to be helpful since if you have any black pixels in the images then since they will also change to purple too. @devang if you want to use this option then you have to remove the mask option from falsecolor command in these lines.

You can read more about it on falsecolor2 page:

One word, “camaraderie.”

Thank you, both for sharing your thoughts and resources. I will check them and report back where I land.

Just to share an update

Jon Sargent confirmed that this is being done in .Net and not in Radiance.