Ok old timers. Put on your thinking caps!

Does anyone remember what utility was used to convert BUM maps to either JPG or PNG?

I'm updating an old runtime and there are a handful of BUM bump maps in there. 

IrfanView can open .bum files.

It actually will give a notice, saying that those .bum files are actually .bmp files and offers to rename them for you.

(So you probably could also just rename them manually, so that newer versions of Poser can handle them)

IrfanView can batch convert them, too, into a file type of your choice.

If I remeber correctly, I think Poser 5 also auto-converted .bum files into .jpg's?

Irfanview. That's it!

You might be right on Poser 5 but after a recent move I think a lot of my old software dvds didn't make it 8-(

Ok old timers. Put on your thinking caps!

Does anyone remember what utility was used to convert BUM maps to either JPG or PNG?

I'm updating an old runtime and there are a handful of BUM bump maps in there. 

You can still use .BUM files in Firefly in later Poser versions by plugging them into the gradient bump socket on the Poser surface node.

The IrfanView method for converting .BUM to .BMP will produce a coloured map which is more like a variety of normal map than a greyscale bump map. It may 'sort of' work in some circumstances but won't be strictly correct. There isn't an easy way to deconvert BUM maps, although I have a vague memory of someone posting a method which used Photoshop. If I can recover it I'll update this thread.

noxiart posted at 5:43 PM Sun, 5 February 2023 - #4455368

If I remeber correctly, I think Poser 5 also auto-converted .bum files into .jpg's?

Not quite, sorry. Poser 5 would convert RSR thumbnails into PNG, although that feature was eventually dropped - can't remember at exactly which version.

English Bob says:

>> You can still use .BUM files in Firefly in later Poser versions by plugging them into the gradient bump socket on the Poser surface node.

I've searched through my saved tips 'n' tricks file, and can't find anything on the subject. I seem to recall that the method I saw was Photoshop specific, and since I don't use PS that would explain why I didn't preserve it.

A .BUM map has information only in the red and green channels: the blue channel is always zero, which explains the khaki hue. From memory, there's a small shift of a few pixels between the two channels, which you'd have to undo to perform an accurate deconversion. If you have an old asset which includes both .JPG and .BUM maps you may be able to reverse engineer the process.

However, bear in mind that there was a bug in the BUM conversion in the Windows versions of Posers 3 & 4. My less-than-scholarly analysis is preserved here, but bear in mind that the links in that article have rotted since Renderosity changed their forum links.

Alternatively, you could just convert those remaining BUMs to greyscale and have done with it. The whole thing seems to be more trouble than it's worth. :)

Thanks @EnglishBob appreciate your looking into it.

Well I downloaded Irfanview, and unless there is a plugin for BUM, it no longer seems to support the format.

So I tried the other trick of renaming to BUM, where I saw the pukey green color. I loaded those into Knald as normal maps, and was able to export a height map. Seeing as these BUM maps go back to Poser 1 figures (LOL yeah, that old!) I think that is good enough for now 8-)

DCArt posted at 5:28 PM Sun, 5 February 2023 - #2977128

Ok old timers. Put on your thinking caps!

Does anyone remember what utility was used to convert BUM maps to either JPG or PNG?

I'm updating an old runtime and there are a handful of BUM bump maps in there. 

You can still use .BUM files in Firefly in later Poser versions by plugging them into the gradient bump socket on the Poser surface node.

Apparently not in 11...

That room help appears to be incorrect. There is a Bump input for standard grayscale maps on the PoserSurface node. The "Gradient Bump" channel discussed there above is actually for legacy BUM maps. 

The manual shows it correctly on page 340 of the Poser 11 PDF manual. It's mentioned again on page 362 that the Gradient Bump option is for legacy BUM files.

I'll fix that for P13

No such input for Physical Surface or Cycles/Principled BSDF though.

Thanks for catching that primorge. It's fixed already. 8-)