This test program uses OpenGL (Mesa) to simulate camera input,and writes decoded Data Matrix streams to STDOUT.Right-click on the window to cycle through the test images.  Toadd your own images for testing, just overwrite any image in thelibdmtx/test/test_images directory with another 256x256 PNG file.If you want to add brand new images then you will have to updatethe gFilename[] and gFileCount variables at the top of gltest.cto include them.