MPP question

[Benjamin Gilbert]

On Thu, Aug 18, 2016 at 03:40:59PM +0000, j.hudecek--- via openslide-users wrote:
> I'm using openseadragon with scalebar plugin to display digital pathology
> slides from a Hamamatsu scanner with a scale bar.  I've converted them
> from .ndpi files with VIPS (which uses OpenSlide I believe).  How should I
> initialize the mpp (microns per pixel) in OpenSeaDragon using the
> openslide.mpp-x from the vips-properties.xml?  I tried multiplying the
> number (0.2271) by 1 million (seemed like a good guess) but I'm still off
> by a factor of 20 or so.

Hi Jan,

OpenSeadragonScalebar expects pixels per meter, so the correct calculation
is (1e6 / MPP).

--Benjamin Gilbert