Extracting bar code label and overview image from MRXS slide

[Benjamin Gilbert]

On 08/01/2014 10:30 PM, Tom N. wrote:
> This is the slide that I used in the test.

Well, you were absolutely right, and your particular slide had nothing 
to do with it.  The good news is that it's not an OpenSlide bug.  :-)

When reading associated images, VIPS has to convert from premultiplied 
ARGB in one 32-bit integer to non-premultiplied RGBA in individual 8-bit 
samples.  It isn't doing this, so on images with no transparency, on 
little-endian systems, the result looks exactly like BGRA.  This bug has 
been around since at least VIPS 7.28.3, and apparently no one noticed 
until now.

--Benjamin Gilbert