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        [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