Project # 2007-506 PACDEX

PACific Dust EXperiment

Principal Investigator(s):  Jeffrey L. Stith, et al.

NSF/NCAR Gulfstream V (N677F)

RAF Logo, 5,367 byte png


Digital Image and MPEG Movie Information

written by S. Beaton, NCAR/RAF, 2008-04-10



Digital Camera Information

The forward-facing camera is located in the right wing pylon.  It is a Point Grey Research Hi-Res Flea - Color, 1024x768 resolution.  The Navitar DO-412 lens has a focal length of 4 mm.  Because of vignetting by the window, the effective field of view is about 45 degrees diameter with some barrel distortion.

Images were acquired once per second and stored as JPEG-compressed files, roughly 50 kB each.  No processing of the images was performed beyond converting the raw pixel signal into a 24 bit color image.  The UTC date and time are encoded in the filename as YYMMDD-HHMMSS.jpg.  These are the archived images stored in one-hour TAR files. The TAR files have file names with encoded flight number, date and time period as [RTF]F##.FWD.YYYYMMDD.HsMsSs_HeMeSe.jpg.tar, where:

          R = research,  T = test,  F = Ferry
         ## = flight number
        FWD = forward-looking
       YYYY = 4-digit year
         MM = 2-digit month
         DD = 2-digit day
     HsMsSs = 6-digit start time (HMS)
     HeMeSe = 6-digit end time (HMS)
    

Movie File Information

For the MPEG-4 movies each image was processed with the Linux ImageMagick toolkit.  The image was first cropped to 768x720 pixels.  Sharpening and gamma adjustments were then performed [SHARPEN(0.0x1.0), GAMMA(1.1)].  Each image was then annotated on the right side of the image with the flight data corresponding to the time derived from the image name and the resulting image scaled to 704x480 pixels.  These 1-second annotated images were compiled into a video stream running at 15 frames/s, 500 k bps data rate using the MPEG-4/h.264 (AKA "MPEG-4 Part 10" and "AVC") codec. If you notice that the movie times do not match the netCDF data file times it is usually because A) The camera starts about 10 seconds after takeoff when the anti-ice power is applied (powers the camera) and B) The movie is stopped early if darkness falls.

The movies can be played by Quicktime 7 or later (Mac and Windows), xine (linux) and mplayer (multiplatform, not tested).

Quicktime (Apr. 2008)Machttp://www.apple.com/quicktime/download/
Quicktime (Apr. 2008)Winhttp://www.download.com/QuickTime/3000-2139_4-10002208.html
xineLinuxhttp://xinehq.de
mplayerLinux, Mac, Winhttp://www.mplayerhq.hu/homepage/design6/info.html

Flight-Specific Comments

RF01:   Sapphire window installed over existing abraded window.  Camera started a couple minutes late.  Movie ends with data file.
RF03:   Stopped for darkness.
RF04:   Stopped for darkness.
RF05:   Ends 5 minutes early.
RF10:   Stopped for darkness.
RF11:   Ends 2 minutes before touchdown.
RF13:   Sapphire window fell off between end of RF12 and start of RF13 so everything is a little hazy.  Stopped for darkness.
RF14:   Stopped for darkness.  No sapphire window.

Last update: Tue Apr 29 17:17:47 GMT 2008