jcupitt/libvips — pull request #6 by bgilbert (2011-12-08 20:22:06+00:00)
Title: Support reading virtual slide files with OpenSlide

[OpenSlide](http://openslide.org/) is a library for reading several formats of virtual slide file. These files are produced from glass microscope slides by specialized scanners and have a variety of unusual features. As the slide files are typically very large, OpenSlide provides access to arbitrary regions of a slide without loading the entire image into RAM.

This patch series adds OpenSlide support to VIPS.

Implementation notes:

* Since it appears that `im_*2vips()` is going to be deprecated in favor of `VipsFormat`, `im_openslide2vips()` is not exported. As a result, gtk-doc is not including its documentation in the reference manual.

* When libvips is built against OpenSlide <= 3.2.4, opening large non-pyramidal tiled TIFF images is very slow. (An unnecessary SHA-256 is being computed over the entire file.) This is fixed in OpenSlide git.