Binary-file format
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Camera and histogram file format
The first line of the file always contains a thirteen-digit number
which is the time (in UTC) corresponding to the contained data as Unix
time (milli-seconds since 1/1/1970). The second line contains a
floating point number (in human readable ascii format) representing the
lower limit if the scale and the third line the upper limit. The next three
lines contain the three numbers displayed on top of the graphics,
usually the minumum, median and maximum data value. Everything
after is considered to be the data. For some restrictions of the HTML
GET mechanism available in JavaScript the data must not exceed ascii
character 127. So the full scale displayed, either in colors or as
graph, is from 0 to 127. Eeach ascii character represents one entry in
the camera or the histogram. The number of entries in the histogram can
be between 0 to hundreds, although more entries than a typical screen
has pixels does not make much sense. Keep in mind that the data is
reloaded every few seconds and the larger the file is the higher the
network traffic is. For the camera the number of entries is fixed and
must either be 40 (boards), 160 (patches), 320 (HV channels) or 1440
(pixels). They must be ordered by crate, board, chip, group, channel.
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