uint16 to double for images

[Bayley, Christopher]

Hello;

 

I’m trying unsuccessfully to extract the data found within a grayscale image of class uint16.  The image is loaded into Octave with imread(filename), and class reports that the data is stored as a uint16, however, when I try to examine individual values within the matrix, they appear to be in the range of 0-255 (i.e. uint8), and even by casting the uint16 as a double (i.e. double(Image(1,1)) where I is the image, I still only get 0-255 gray levels.

 

How do I extract the 16bit data contained in the images?

 

Regards

 

Christopher Bayley