Tag Archives: graphics

Flightaware route histogram

Flightaware + Fyre:

The above image is part of a histogram generated from Flightaware’s 24-hour time lapse. Click the link for the uncropped version. The original video is a Quicktime wrapper around individual PNG frames. I used mencoder to strip off the Quicktime wrapper, then a small Python script split the video streams into individual frames, decompressed them, and plotted a histogram of each red dot. The script generated a data file which was rendered using a patched version of Fyre 1.0 SVN.

Oversampling in Fyre

Despite Fyre 1.0 being “completely done” for a while now, I have to nitpick it occasionally. I recently composed an image which brought out a particularly bad oversampling bug in Fyre.

Fyre implements antialiasing using an oversampling technique, much like FSAA on modern video cards. In Fyre 1.0.0, we just chop each pixel into an even 2×2, 3×3 or 4×4 grid of subpixels. Making an analog signal processing analogy, it increases the sampling frequency and adds a low-pass filtering stage after the samples are taken. There is still the potential for very high-frequency features in the original signal to alias, and produce undesirable patterns in the resulting output.

In the current development version of Fyre 1.0, I’ve added ±1 subpixel of spatial noise prior to sampling, which gives us the missing low-pass filter that should keep us below the Nyquist limit. Intial results look good:

Before: Fyre 1.0.0 release, 3x gamma-corrected oversampling on a regular grid

After: Fyre 1.0 SVN, 3x gamma-corrected filtered oversampling

Gimp 2.3.7

I finally got around to installing the latest development release of Gimp, 2.3.7. It’s definitely worth a try. The menus have been rearranged a bit- a little disconcerting for a long-time Gimp user, but the new layout makes a lot of sense. It’s always nice to see the new splashscreens.. but I’m still a little bitter that my masterpiece didn’t win the contest 😉

The coolest new toy in Gimp 2.3 has to be the foreground extraction tool. Now make hackergotchis with hardly any effort at all! I bring you a banana bread hackergotchi:

Tasty floating banana bread!