Operating instructions

Using the sdisplay Program
The sdisplay program is used to view video files generated by the Video Sentinel box and
the sentuser program. These files have file names that indicate when the file was created.
They look like this:
v20020115_034512.45
The format is vYYYYMMDD_hhmmss.ss, where v is just v, YYYY is the year, MM is the
month, DD is the day of the month, hh is the hour, mm is the minute, and ss.ss is the
second (to a resolution of 0.01 seconds).
You start the sdisplay program by opening a new terminal window and typing:
./sdisplay &
When the program starts, it opens a 640 x 480 pixel window, looks for the first file in the
current directory that begins with "v2", and plays the video from that file. The file name
is shown in the window caption. The file contains the complete reference frame from the
original captured video but only a 128 x 128 pixel subset of each subsequent frame,
centered on wherever changes were seen. The movie consists of a fixed background
image upon which a smaller sub-image movie is shown like a moving sprite. As the
movie is played, 4 white pixels mark the corners of the 128 x 128 pixel sub-image.
The interface for the sdisplay program is extremely simple, consisting entirely of single
keystroke commands. These commands are listed below:
<space-bar> Replay the current video file.
<right-arrow> Load and play the next video file that begins with "v2" in the current
directory. If there are no more files, replay the current video file.
<left-arrow> Load and play the previous video file that begins with "v2" in the current
directory. If there are no previous files, replay the current video file.
<shift right-arrow> (Press right arrow while holding down shift key.) Load the next
video file and show only the first frame. This is much quicker than playing the entire
movie so it can be useful when you want to quickly scan through a number of files.
<shift left-arrow> (Press left arrow while holding down shift key.) Load the previous
video file and show only the first frame. This is much quicker than playing the entire
movie so it can be useful when you want to quickly scan through a number of files.