WindDisplayMapping Trouble

[BrianSetlik]

I have been using Vision for several years and have a new problem. I've written many vi's for imagers with 8-bit, 10-bit, and 12-bit data. Using the WindDisplayMapping vi I could get a nice looking image in my display window even when the data doesn't span the whole dynamic range by using 90% Dynamic. Now I am writing for a 14-bit imager and regardless of what I set the mapping to be, it always presents the same full dynamic (therefor washed out) image. If I save the image as a tiff and open it back up in Labview using a display mapping and display window like before, the image looks just fine. Has anyone seen such behavior before. I can provide any additional info needed to debug this.

Thanks

[Jason N]

Haven't seen this behavior before, but this KB from ni.com might give an explanation for it:  http://digital.ni.com/public.nsf/websearch/F5AFF8F35700C1DC862570A4005D127D?OpenDocument

Basically, unless you specify otherwise, the image will be read from the file as an 8-bit image, causing it to look brighter and not washed out.  One thing that you could try to display the image correctly without saving it to a file first would be to take a histogram of the image to find out the maximum and minimum pixel values.  Then apply these values to the WindDisplayMapping vi using the Given Range setting on the Conversion Policy input.  This should ensure that no values outside of the maximum and minimum values in the image are displayed.

Jason N