The C-130 flew two digital cameras for in-flight video capture: forward and downward-looking. The 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 degrees with some barrel distortion. This camera is located on the right wing pod.

The downward looking camera is a Point Grey Research Grasshopper (GRAS-14S5M) monochrome camera, 1280 x 960 resolution equiped with a Sony zoom lens set at about 15 mm focal length giving a field of view of 30x23 degrees. It is located on the belly of the plane. The left side of the image is to the front of the plane, and the top of the image is to the right of the plane.

Images were acquired once per second and 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.

Preliminary H.264 compressed, half-resolution movies (.mov) 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 image was then annotated in the lower left with the time the image was recorded. These 1-second annotated images were compiled into a video stream running at 15 frames/s, 1000 k bps data rate.

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

J. Aquino

S. Beaton

NCAR/RAF

2011-11-22