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PLOT /SCALING
[GREG2\]PLOT /SCALING Type [Low_cut High_cut]
Defines the type of transfer function to be used. Type can be LIN(EAR),
LOG(ARITHMIC) of EQU(ALIZATION), and the Low_cut and High_cut are the
lowest and highest represented values respectively. The default "cuts"
are the image extrema. The current cuts are stored in the variable array
CURIMA%SCALE. The current scaling (as an integer code) is stored in the
variable CURIMA%SCALING. The LOG transfer function computes the loga-
rithm of the pixels values, so does not like negative or null pixels.
The EQUalization scaling tries its best to put the same number of pix-
els in each slot of the color table, thus increasing immensely the visi-
bility of low-contrast images. This scaling mode has problem (and warns
user) when a large number of pixels have exactly the same value (i.e.,
no contrast at all). Beware that most "real" images are obtained with
receivers working with a small number (11 to 16) of bits, thus restrict-
ing the range of available Real numbers in the data.
The SIC variables CURIMA%EQUAL%NLEV, CURIMA%EQUAL%LEV and CURI-
MA%EQUAL%HIST contain the number of different levels computed in EQUAL-
IZATION mode, the values of these levels, and the number of pixels in
each level, respectively. Useful to know which contour levels to draw,
and necessary for the WEDGE command.
Gildas manager
2014-07-01