Re: Tiff monchrome memory usage

[John Cupitt <jcupitt gmail com>]

On 12/22/05, David Stevenson <david avoncliff com> wrote:
> I am using tiff files that are 9000x6000 pixels black and white.
> ( they are schematic drawings intended to print A0 size )
> I calculate this as just under 8meg at 1 bit per pixel, however when I
> open in Gimp or Eye of Gnome they seem to use over 200meg of ram, which
> pushes my 256meg Macmini into swapping and makes the files unusable.

I did some tests with a 10k x 10k pixel 1 bit image on my laptop. gimp
needs just over 200MB of RAM, so I guess they represent the image as 8
bits per pixel plus a bit. eog needs about 350MB, so they might be
using RGBA.

I maintain an image processing package called nip and it needs just
over 30MB to view and manipulate the image. But it's not a paint
program and can be tricky to use :-( if you're curious, you can
download from:

http://www.vips.ecs.soton.ac.uk/

John