The CMUCam3 has a feature (in CMUCam2 emulation-mode) that allows it to dump a JPEG image (in binary format) back via serial.

I am capturing the incoming data using the serial.read() function, and placing them into a large char array (I tried using an int and a byte array before as well).

Doing a println on a char-converted copy of the int array in Processing appears to reveal what looks like the JPEG file, with the two starting bytes 0xFF+0xD8, the JFIF JPEG header et al, but where I'm stuck at is trying to save this array into a file.

I have tried the saveStrings() function but that seems to convert the bytes into something else (alphanumeric text and readable chars, probably).

This leaves me with saveBytes(), but I don't quite know how to correctly convert ints to java's signed bytes; the 0-255 values of the ints wrap around if I just do a byte(int) conversion (correct me if I'm wrong), and simply subtracting 128 from the int doesn't work either.

So my question is this: how do I save the JPEG framedump from the CMUCam3 (or any other serial device, for that matter) while preserving its binary form?


Any thoughts?