I've done TIFF handling in C as well, and it's always going to take time to process images. The free "libtiff" may be over-engineered for your task however, and you can probably find some shortcuts if your problem is narrowly constrained. The problem with many TIFF libraries is that in order to support all possible TIFFs, there's a lot of overhead in their parsing and encoding which may not apply to you.

I recommend you do some calculations of the bytesize of the image, versus the bandwidth of harddisk->memory->harddisk. If the software itself isn't killing you by being stupidly redundant, the hardware is going to be your bottleneck.

--
[ e d @ h a l l e y . c c ]