bbm (deluxe paint enhanced images) support

[gilles504]

hello,
it seems .bbm is not correctly diplayed

There is a trick for odd X size in bbm but I suppose here RLE is not taken into account.

[deus-ex]

You should attach an example .bbm image to support your claim.

[gilles504]

phpbb does not permit .bbm extension in attachment (or maybe it's firefox in mime types)

but you will find it here:
http://www.alternative-system.com/files/magic1.bbm

bbm is a brush, most of brush are odd size when a grid is used. I've seen that some even sized bbm files are ok so I think that 16bit align is the issue here.

[deus-ex]

Thanks for providing an example.

phpbb does not permit .bbm extension in attachment (or maybe it's firefox in mime types)

True, but you can trick the system. Add a permitted extension to the file name and provide some info to remove that extension before attempting to view it. Or actually compress the image to a ZIP, RAR or 7-Zip archive.

And for everyone interested, this is what the image is supposed to look like:

[gilles504]

Thanks, last time I saw this one was on my 486 with DPE (or maybe with doxbox)

to be close to perfection bbm should use the transparency color because it's a brush. (tranparency is defined somewhere in the "BMHD" section if I can trust my old Borland C code).

[deus-ex]

The image you provided is a 8-bit image, i.e. there is no additional alpha channel included. None of the colors from the palette was flagged as transparent. I fixed that now in the PNG-format example:

[gilles504]

just checked with DPE and the tranparency is defined (I think it's the 0xFF white at the end of the palette):
in my old code section "BMHD" is len(32) brushx(16) brushy(16) ??(16) ??(16) ??(16) ??(16) transparency(16) ??(??)

If I remember correctly dpe uses the last background color to define the brush transparency color.

[deus-ex]

Ah, I understand. The program I used to display the .bbm image and alter the palette does not recognize the transparency flag. I'm glad it is able to load and display this format since it is not officially supported, but it appears to share similarities with the supported Interleaved Bitmap format (.iff, .lbm). And yes, I also set the last color in the palette (white) to transparent.

EDIT: Changed "does recognize transparency" to "does NOT recognize transparency", obviously.

[gilles504]

lbm and bbm are nearly identical and have the same amiga origin (3 char name is a PC/DOS convention for deluxe paint PC, on amiga an image does not always have a suffix but .iff is common for all iff formats (not only images but also text, audio and music))