fftpaint golan.PROBLEM SET 1

The fftpaint applet invites you to import, edit and scribble on a grayscale image. View this image in the frequency domain by pressing the doFFT button -- this produces a representation of the image's power spectrum. Now you can edit this power spectrum, but be careful -- small changes can make a big difference in the original! Convert the power spectrum back into a normal image by pressing the doIFFT button.

Parts one, two and three of Prof. Maeda's assignment have been rolled together into a single Java applet.

Compatibility. fftpaint is known to work in Internet Explorer 4.x from within the Windows95 OS. As of its 9/17/98 version, it fails to work in the WindowsNT OS (problems, I suspect, with MemoryImageSource and PixelGrabber). The applet also appears to be incompatible with Netscape browsers, owing to security violations incurred when opening locally-stored images. I haven't tested it on the MacOS.

Special features. fftpaint provides two variable-width brushes: a continuous-line 'pencil', and a randomly-dithered 'airbrush'. These are selectable via the 'line/spray' toggling button. fftpaint also permits a circularly-constrained paint mode, enabled by holding down the SHIFT modifier key. The FFT code used in fftpaint was adapted from code in Lyon and Rao's "Java Digital Signal Processing" book.

The photographs were taken very early this morning at Joanie's diner. Also present were Ben and Elise. We shared a bright and inexpensive breakfast of pancakes, fried bananas and eggs.