Hi,

I have a large (1000px x 20000px) Image object that I am trying to
scale down. It is in the 8bppIndexed format.

I am currently creating a new 24 bit Image object and using the
DrawImage method to do the scaling. But creating the new Image object
takes too much RAM (~70 MB) for the deployment machine. This object
cannot be in the 8bppIndexed format because then I cannot get a
Graphics object from it.

So I am looking for an alternative way to scale it down w/o creating
the 24 bit Image. Is it possible to scale an image by using its array
of bytes?

Any tips are greatly appreciated

Thanks,

Dave

You could unpack it to16bpp instead of 24bpp.

You could also use GDI StretchBlt via p-invoke which works with all bit
depths

<davermcl (AT) hotmail (DOT) com> wrote

<davermcl (AT) hotmail (DOT) com> wrote

What size are you scaling down to? You should be creating your 24bit bitmap
at the smaller size, not 1000x20000.

Thanks for your reply!

But I've resolved this issue by creating a 16bit Image instead of the
default of 32bit. The memory usage still isn't as low as I would like,
but at least the deployment machine doesn't crash anymore.