To minimize the file of diagrams we tried other formats, too, like JPEG, PNG and TIFF. JPEG brings a BMP file of about 200 KB down to 50 KB. PNG brings a BMP file of about 200 KB down to 8 KB. TIFF doesn't change the size of the file.
But as soon as we import the original BMP or the new PNG, JPEG or TIFF files into MS Word and try to save, we get Word files of the same size. All 209 KB -- the only exception is JPEG. That gives a file of about 1200 KB. Is there a solution or is it inevitable if we use MS Word?
One solution is to link the images in from the outside, rather than embed them exclusively. In Office XP, use the command Insert | Picture | From File, and then select Link to File from the drop-down list in the action button next to the filename dialog. The image needs to be kept in the same location consistently for this to work (probably a network-accessible drive if you're using this in multiple locations), but this way you can simply maintain a link to the image rather than embed the image directly. If you want to keep things portable, though, the image needs to be embedded in the document, and you can use JPEG or PNG/GIF compression depending on the size of the image.
This was first published in June 2003