Digital Camera Imagery and Movie Notes

During MPEX, the GV flew a forward-looking digital camera for in-flight video capture.

This forward camera is a Point Grey Research Hi-Res Flea - Color, 1024x768 resolution. The Navitar DO-412 lens has a focal length of 4 mm and the field of view is about 62° x 48° with some barrel distortion. This camera is located on the right wing pylon. The camera was not turned on until about 1100-1200 UTC when there was sufficient daylight to record images.

Images were acquired once per second. Images are stored as JPEG-compressed files, roughly 100 kB each. No image processing was performed beyond converting the raw pixel data to 24 bit color images. Applying a sharpening filter as is ordinarily done by consumer digital cameras will considerably improve the appearance. The UTC date and time are encoded in the filename as YYMMDD-HHMMSS.jpg.

H.264 compressed, half-resolution movies (.mp4) were created. Each 1-second image was processed with the linux ImageMagick toolkit. The image was first cropped to 512x384 pixels. Sharpening was then performed [SHARPEN(0.0x1.0)]. Each forward-looking image was then annotated in the lower left with the time the image was recorded and in the upper right with the pointing. For final movies, data values at the image time for a select set of data parameters chosen by the researchers were appended to the right of each image block. These 1-second annotated images were compiled into a video stream running at 15 frames/s, 1500 kbps data rate.

The movies are playable with Quicktime, Windows media player from Windows 7, mplayer, VLC, and others.

Flight comments:

None



J. Aquino

S. Beaton

NCAR/RAF

2013-07-10