What are the units for the crop attributes in the imagedata element of WordML?

Question

I am trying to extract images from a document saved as WordML. Some of the images are cropped from a single resource using attributes on the imagedata element eg:

<v:imagedata r:id="rId8" o:title="" cropbottom="32429f" cropright="44328f"/>

What are the units for the cropbottom and cropright attributes?

I have done some web searching and according to http://msdn.microsoft.com/en-us/library/bb229565%28v=vs.85%29.aspx the units should be percentages but don't seem to be.

In the example above the resulting image should come from the top left of the original and be a third of the width and half the height.

Answer 1

I'll answer my own question in the hope that it is useful to someone else.

According to ImageData Class - Office 2010

CropBottom ... specifies the how much to crop the image from the bottom up as a fraction of picture size. Default is 0. This numeric value can also be specified in 1/65536-ths if a trailing "f" is supplied. For example, a value of "52429f" represents 52429/65536 or 0.8.