Monday, June 15th, 2009
I have been trying to get a sense of how much video processing my computer can do. A 2.2Ghz Intel Core 2 Duo can capture 640 x 480 @ 30 fps from a Logitech Vision Pro webcam while simultaneously playing four previously captured clips encoded with H.264 and AAC mono audio. Capturing video while playing more than four videos results in dropped frames.
This plot shows a pretty linear falloff in captured framerate as the number of video files being played during capture is incremented.
Sunday, June 14th, 2009
I needed to know the geometry of some common LCD panels for a project I’m working on. I couldn’t find a convenient chart, so I am contributing this one to the Internet. I worked out the X and Y values with some simple trig. An alternative estimation based on resolution multiplied by pixel pitch yields similar results ±0.125”.
| H” | X” | Y” | AR | X res | Y res | a° | b° |
|---|---|---|---|---|---|---|---|
| 15 | 12.0 | 9.0 | 4:3 (1.33) | 1024 | 768 | 53.13 | 36.87 |
| 17 | 13.27 | 10.62 | 5:4 (1.25) | 1280 | 1024 | 51.34 | 38.66 |
| 19 | 14.84 | 11.87 | 5:4 (1.25) | 1280 | 1024 | 51.34 | 38.66 |
| 18.5 | 16.13 | 9.07 | 16:9 (1.77) | 1366 | 768 | 60.65 | 29.35 |
| 15.4 | 13.06 | 8.16 | 8:5 (1.6) | 1440 | 900 | 57.99 | 32.01 |
| 17 | 14.42 | 9.01 | 8:5 (1.6) | 1440 | 900 | 57.99 | 32.01 |
| 19 | 16.11 | 10.07 | 8:5 (1.6) | 1440 | 900 | 57.99 | 32.01 |
| 20.1 | 16.08 | 12.06 | 4:3 (1.33) | 1600 | 1200 | 53.13 | 36.87 |
| 19 | 16.11 | 10.07 | 8:5 (1.6) | 1680 | 1050 | 57.99 | 32.01 |
| 20 | 16.96 | 10.60 | 8:5 (1.6) | 1680 | 1050 | 57.99 | 32.01 |
| 22 | 18.66 | 11.66 | 8:5 (1.6) | 1680 | 1050 | 57.99 | 32.01 |
| 21.5 | 18.74 | 10.54 | 16:9 (1.77) | 1920 | 1080 | 60.64 | 29.36 |
| 23 | 20.05 | 11.28 | 16:9 (1.77) | 1920 | 1080 | 60.64 | 29.36 |
| 24 | 20.35 | 12.72 | 8:5 (1.6) | 1920 | 1200 | 57.99 | 32.01 |
| 25.5 | 21.62 | 13.52 | 8:5 (1.6) | 1920 | 1200 | 57.99 | 32.01 |
| 30 | 25.44 | 15.90 | 8:5 (1.6) | 2560 | 1600 | 57.99 | 32.01 |
Thursday, May 28th, 2009
These are our results from an online Farnsworth-Munsell 100 hue test that Sylvia found on the Internet. The test involves arranging color swatches into a continuous spectrum of hues. The bars indicate which hues we were unable to arrange correctly and I’m not sure what the height of a bar means.
As you can see, we got very different results depending on the display used for the test. A proper FM100 test kit costs about $700 and has to be completed under controlled (D50) lighting conditions. Nonetheless, it’s fun to play with the pretty colors and create some order from the randomized initial state.
Related Links: Color Management Systems Lab at RIT where I was a labbie in 2002; Munsell Color Science Lab at RIT
