Re: using 24-bit colour images: reprise
Scott Raney (raney@metacard.com)
Fri, 21 Feb 1997 09:52:08 -0700 (MST)
On Fri, 21 Feb 1997, BullShifter wrote:
> > The reason I ask is that I have prepared a stack into which I have
> > imported some 24-bit color images (each using about 18K colours, and
> > probably a fairly similar set to each other). They are of skin, and
> > they appear BLUE in MetaCard. Whilst fiddling around with the local
> > metaManiac, it appeared that the problems occurred once we went above
> > 256 colours. Thus, we suspected that we have hit some 256 colours
> > barrier.
> > Does such a barrier exist? Can it be modified? If so, how???
>
> [Raney:]
> There's no fixed boundary here, though remapping 24-bit color images
> down to 8-bit is no walk in the park.
>
>
> In actual fact, I DO NOT want to operate with 8-bit colours. I want to
> operate in/with 24-bit. The 255 colours thing was just fiddling.
>
> (Also JPG is out, BMP is in.)
BMP does minimal or no compression, and so is an inappropriate format
to use in stacks that you plan to distribute to others (of course if
you plan to distribute your stacks, doing everything in 24 bits is
probably a mistake anyway). Even if these are just for your own use,
you pay a pretty big price in disk space and RAM usage by using BMP.
> So, any idea why my skin is blue, and how it may be remedied?
The only sure workaround is to use JPEG for your 24-bit images. But
this may be a bug in the engine, in which case we'd greatly appreciate
it if you could email the image to support@metacard.com so that we can
make sure it gets fixed.
Regards,
Scott
> B-)
>
***************************************************************
Scott Raney raney@metacard.com http://www.metacard.com
Any sufficiently advanced technology
is virtually indistinguishable from magic -- Clark's law