Bas Relief from photo

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I have been trying to create a bas relief effect using heightmaps and have not been able to create good stuff. For example when I use a face I need the black of the hair to come forward, more than the grays of the face. Curios to know if any of the brilliant minds out there have successfully made it happen. Any pointers/examples are greatly appreciated.

Thanks

Umesh
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post that example (Face )
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I will, its a simple image of a face being used as a height map.
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The problem with creating bumps or displacements from COLOUR ONLY is that you most often cannot be sure that ONLY those areas that you want to “emboss” use the colour you define for “extend outwards”. The same colour may be used all over the place, either creating unmanageable noise or offsetting the displacement height massively so that manual clean-up after the fact takes longer than doing it by hand from the beginning.

Since I do this kind of R&D for a living, I cannot provide an out-of-the-box solution. But think along these lines: Can you better separate your colour in non-RGB spaces so that the “embossed” colours are more “unique-ish”? Can you apply a high-pass (or maybe a low-pass) filter to mask out areas where you do NOT want embossing to appear (hint: This is a key-process in getting good results)? Can you deduct light directions from your image data (hint: This is GOLD STANDARD for physically plausible results)? Can you use GRADIENTS instead of colour?

If you are looking for a “cheap” solution, have a look at Github or do a search run on the interwebs, there are dozens of tools that claim to do photo-to-bump-map conversions. Their results CAN BE good enough (especially with “lab condition” photos) and depending on your output needs it may be quite straight forward to reproduce what those tools do. However, as long as you ONLY have a colour photo (maybe even with destroyed detail, read, a jpeg) you are limited to “faking it”. OR you apply a machine-learning computer-vision step, that might give you “better” results.


Marc
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Out of here. Being called a dick after having supported Houdini users for years is over my paygrade.
I will work for money, but NOT for "you have to provide people with free products" Indie-artists.
Good bye.
https://www.marc-albrecht.de [www.marc-albrecht.de]
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What I normally do is take the original photo image and play with it in something Like Photoshop - and create/run it through color/misc. adjustments saving out as an export - making note of it's resolution.

Create grid in Houdini with same resolution and bring the image in using an attribute from map node.

Run that through a wrangle for height adjustment with any code that suits your purpose.

Afterwards you can reapply color attributes from another Photoshop exported layer or even the original image.
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Thanks @malbrecht and @BabaJ for the pointers. I have not tried the image separation processing approach. I think it makes a lot of sense. Gives me plenty to move on in figuring out the next steps.
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