How to read a large .img file

I have a 4 GB image file that Matlab is choking on. I'd like to get this file into Matlab. Here is the code that makes my computer freeze:

fid=fopen('myimage.img','r','l');
M=fread(fid,[48333,41779],'uint16');
fclose(fid);

Equivalent code works well for a similar, smaller image, but this image is large. Subsetting into quadrants or sixteenths would be fine by me, but I don't know how to subset for a .img file. I know subsetting a tiff works with imread. Any suggestions for getting this big image into Matlab?

[Ashish Uthama]

If you have a current version with Image processing toolbox, this blog post might be useful: "Dealing with “Really Big” Images: Block Processing"

Answer 1

[José-Luis]

Sounds like a job for memmapfile()

 doc memmapfile

Alternatively, you could split your image beforehand.

[Chad Greene]

Thanks for pointing me to memmapfile, José-Luis. This might just be the ticket.

[José-Luis]

Glad to help.