New Detail tool and frequency bend

[tomczak]

In the new tool, is it possible to apply threshold(s) to clone a range of spacial frequencies (i.e. restrict copying on the high frequency side as well)? This may have a visual advantage in some cases:

viewtopic.php?f=5&t=894

[tomczak]

*band

I'm fiddling with the Detail tool. One idea came to mind: predicting the visual effects of copying some spacial frequencies and not others may not be that intuitive. I was thinking about how it would be possible to change the parameters (especially blur radius) a posteriori (when the brush stroke has been already painted. The best I can think of now is paint, undo, change the radius, paint again, undo, change the radius...

[tomczak]

Does the Detail tool use the Bilateral/Guided filter to determine the low-pass version of the image in a similar fashion as the Advanced Brightness Curve does? I would be interested to see what Threshold and Detail sliders would do in this tool...

[jsachs]

It uses Unsharp Mask -- Guided filter would be much slower. Also, I do not believe it makes much sense to try to copy detail over hard edges so any advantage of using the Guided filter would likely be wasted. The added complexity in the interface would also be a drawback.

I was thinking of adding an option to display the blurred version of the input image which would help set the blur radius as small as possible but still large enough to remove unwanted detail.

[tomczak]

I think that displaying blurred version prior to a paint stroke (or maybe an option to keep the stroke 'live' for adjustments before commiting it) would make it easier to use the new tool.

But I also think that regardless of blurring method some way of thresholding the finest details from being copied over may be quite useful. An example could be smoothing skin blemishes but leaving skin pores alone which I think increases realism as shown in this example: viewtopic.php?f=5&t=894

[jsachs]

I don't think that would add anything useful to the tool and would make the interface more complicated. Here is some quick retouching I did on the sample image using Detail with a Blur Radius of 15.

Detail v1.jpg (14.79 KiB) Viewed 2026 times

Also, for the next release, I added a button to let you see the blurred image.