[magick-users] tiff convert slow

[Gabe Schaffer]

ImageMagick is designed to be able to handle any size image, but not
necessarily quickly. I would recommend finding a tool that does not
attempt to decompress 1bpp images into 32bpp images in RAM before
processing.

On 9/23/06, Harm de Laat <harmdelaat at gmail.com> wrote:
>
> I have to resample some TIFF-G4 images to a lower resolution.
> At this point the original images are rediculous large:
>
> Image width: 45750 Image length: 31251
> Resolution: 1270, 1270 pixels/inch
>
> I need  to convert these images to a resolution of 300 DPI.
> I use the following command:
>
> convert -verbose -monitor wm_k.tif -resample 300x300 wm_k_300.tif
>
> However, when I run this command on my Ubuntu box, it takes more than 24
> hours to convert ONE image!

The problem here is that even though your image is probably 10 MB on
disk, it expands to 1.4 gigapixels, which is going to require 5.8 GB
of memory for ImageMagick to process it (if you have a Q8 build --
double that for a Q16). The resulting image will be 320 MB in RAM, so
you will need a 64-bit CPU with over 6 GB of RAM available to process
this command quickly. Otherwise it will swap out to disk and take
forever.

GNS