Output Distortion as DU/DV map

If the filter happens to be a surface filter (ones that export normal maps) you can convert those normal maps to dU/dV maps by doing the following operations in Photoshop:

1. Find your normal map and invert the image.
2. Adjust your image by going to colors --> adjust --> Brightness/Contrast and set the following parameters: turn "use legacy" on, brightness should be -17, Contrast to 100.

There is also a corresponding filter: http://www.filterforge.com/filters/9557.html

I think it might be a bit tricky given I don't know what filter you're specifically using but I think the method above should kinda hint at where to go next.

Let me try to better describe what I am looking for...

I am looking for a filter that takes no image as an input - the filter generates its own color data.

I want to use a Noise Distortion component (which requires an input to push around pixels) and output how it will distort an image instead of a distorted image.

Does that help better explain? the Du/Dv filter is nice, but it expects an image as an input as well. I want to calculate the Du/Dv offsets inside the filter from the math going on inside the Noise Distortion component.

Hope this help better clarify. Thanks!

Thanks, that is helpful, although the Derivitive component creates very harsh ouputs. Is there a way to get a smoother result?

Side note: how can I link to a filter i am working on in a forum post?

The dU/dV filter by default has a "smooth" slider Go to your settings tab once you've fixed your filter to your tastes and you can adjust the smoothness of the filter. It seems by default it was set to 0.

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But instead of extracting the Channels and pasting them into a new texture, I'd like to calculate the Height myself and and use the Assemble RGB component to output the result.

Right, the dU/dV filter already accomplishes this. You just need to modify it by loading the noise pattern in there.

You can attach a filter by attaching the ffxml file to the forum. Any filter that you've modified or made should be in one of theses folders Windows: %APPDATA%\Filter Forge 3\My Filters OR on a Mac /Users/<HomeFolderName>/Library/Application Support/FilterForge 3/my filters

I tried the Du/Dv map settings for smooth and blur, but it still doesn't come close to what can be extracted from a normal map.

Here is a side by side comparison of the red channel from a normal map and the red channel of a Du/Dv map with smooth at 100.

I'm trying to create a filter that will generate something more like the normal map channel.

That somehow doesn't seem right since the size param just changes the scale of the output designated by pixel value and doesn't touch on smoothness in any way. I figure if it looks good then it's fine, I just don't see that as being accurately solving the main issue.

I mean in the end if you don't need to balance red and green channels... you can just bypass them all together and the results would be directly coming out of the output of the normal map.

Were you talking about "scale" on the noise component?