how to fix my source code Retrieving Image Data Binary Types from database?

I'm doing research thesis. I am confused with sorce code to retrieving image data binary types from database. I have tried the source code at this link http://www.mathworks.com/help/database/ug/retrieving-binary-or-other-sun-java-sql-data-types.html. but I get an error like this

>>saveimg

ans =

    [2]    [255x1 int8]
    [3]    [255x1 int8]

??? Error using ==> imread at 342 Unable to determine the file format.

Error in ==> parsebinary at 74 [x,map] = imread(['testfile.' lower(f)]);

Error in ==> saveimg at 13 parsebinary(gbr, 'bmp');

Can help me to fix this source code? thanks