PICSTAT -- Closely related to istat but allows evaluation of statistics
over a set of rectangular regions rather than just one. It
also computes these with reject cycles. picstat is meant for
computation of constant values for bias subtraction. The
revised mean value in particular is useful for this.
The revised and robust estimates of standard deviation
can be useful for measuring readout noise. The revised
mean and median are stored as PIC_MEAN and PIC_MEDIAN
in ~/adam/GLOBAL.sdf. If you apply this to integer data,
the plot can look a little peculiar as the data appear 0.5
pixels to the right of the model. This is OK.
Parameters:
IMAGE -- Data frame to analyse.
STREG -- File defining regions with format x1 x2 y1 y2 on each line.
e.g.
1 34 101 500
21 50 601 700
Pixels outside the bounds of the NDF section loaded are
ignored.
CLIP -- Sigma rejection threshold. 2.5 seems to work reasonably
but plot one or two to check. Very small values will lead
to spuriously small values of RMS.
PLOT -- TRUE to plot histogram of values. A gaussian with
mean and rms set to the revised mean and robust
sigma will be plotted over with approximately the
right vertical scaling.
DEVICE -- Plot device
RANGE -- Sigma range for histogram plot
NBIN -- Number of bins
This command belongs to the classes: statistics , examine