1 HISTO_CROSS Cross histogram of two input images/cubes (Image output)
HISTO_CROSS
Computes the cross histogram of two input images/cubes. The output has
the same rank as the input arrays : 2 if images as input, 3 if cubes.
Both inputs must have the same rank. If the input cubes are 3D data
cubes, the third axis must be the same for both. If n1 and n2 are the
numbers of bins for the first and the second input cube respectively,
the result has dimensions [n1,n2] or [n1,n2,nchan] where nchan is the
third dimension of the input cubes. The value at a given (I,J) is thus
the number of pixels in the input images that have the value correspond-
ing to slot I in the first image and to slot J in the second one. For
cubes, this is done in each plane. You can then sum (see SIC\COMPUTE) to
have the cross histrogram for the whole cube.
If the tolerance on the blanking value is positive, the task takes into
account the blanking values of the input cubes.
The output image can be used as input to task REGRESSION to evaluate
some statistical parameters of the correlation. See also HISTO_CLOUD for
a slightly different information.
2 Z_NAME$
TASK\FILE "First input image" Z_NAME$
This is the name of the first image used in the correlation.
2 Z_BIN$
TASK\INTEGER "Number of histogram bins" Z_BINS$
This is the number of histogram slots to be used for the first image.
2 Z_MIN$
TASK\REAL "Minimum value" Z_MIN$
This is the value of the lower bin used for the first image.
2 Z_MAX$
TASK\REAL "Maximum value" Z_MAX$
This is the value of the higher bin used for the first image. If both
Z_MIN and Z_MAX are zero, the extrema are computed from the input cubes.
2 Y_NAME$
TASK\FILE "Second input image" Y_NAME$
This is the name of the second image used in the correlation.
2 Y_BIN$
TASK\INTEGER "Number of histogram bins" Y_BINS$
This is the number of histogram slots to be used for the second image.
2 Y_MIN$
TASK\REAL "Minimum value" Y_MIN$
This is the value of the lower bin used for the second image.
2 Y_MAX$
TASK\REAL "Maximum value" Y_MAX$
This is the value of the higher bin used for the second image. Same as
Z_ if both thresholds are zero.
2 X_NAME$
TASK\FILE "Output cross correlation image" X_NAME$
This is the name of the output cross correlation image.
1 ENDOFHELP