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Package pnm (in pnm.i) -

Index of documented functions or symbols:


DOCUMENT #include "pnm.i"
  makes pnm_read and pnm_write functions available, which see.


DOCUMENT color_image= pnm_colorize(image)

  colorize the width-by-height array IMAGE, returning a 3-by-
  width-by-height array, suitable for use with pnm_write.
  The current graphics palette is used to perform the colorization.
  The keywords cmin=, cmax=, and top= are recognized and have the
  same meaning as for the plf, pli, and bytscl functions.

SEE ALSO: pnm_write, bytscl


DOCUMENT pnm_display, image

  Attempt to display the IMAGE with the pli command and a pseudo-color
  palette.  The IMAGE must be a 3-by-width-by-height array of RGB
  pixel values.  If called as a function, the return value is the
  width-by-height array of pixels which index into the new palette.
  The palette is returned as the external variables red, green, and
  blue.  The new palette is both coarse and slow to compute.

  The size= keyword can be used to set the palette size.  The default
  is 200 colors, the size of all the distribution palettes.

  The flip=1 keyword can be used to flip the image bottom for top.

  The square=1 limits flag is set; use
  to return to the default non-square plot limits.

SEE ALSO: pnm_read


DOCUMENT image= pnm_read(filename)
      or image= pnm_read(filename, noflip)

  read a PBM, PGM, or PPM image from FILENAME.  PBM and PGM files
  result in width-by-height arrays; PPM files result in 3-by-width-
  by-height arrays.  If NOFLIP is present and non-zero, the returned
  image is in exactly the order stored in FILENAME.  Otherwise, the
  height dimension is reversed, since images in the files read top
  to bottom, while the Yorick image plotting commands go bottom to

SEE ALSO: pnm_display, pnm_write


DOCUMENT pnm_write, image, filename)
      or pnm_write, image, filename, noflip)

  write IMAGE to a PBM, PGM, or PPM file called FILENAME.  If
  NOFLIP is present and non-zero, the image in FILENAME is stored
  in exactly the order of IMAGE in memory.  Otherwise, the height
  dimension is reversed, since images in the files read top to
  bottom, while the Yorick image plotting commands go bottom to

  If IMAGE is a 3-by-width-by-height array, a PPM will be written.
  Otherwise, IMAGE must be a width-by-height array.  If IMAGE
  contains at most two distinct values, a PBM will be written,
  otherwise a PGM.  You can force a PGM using the bits=8 keyword.

  If IMAGE is of type char, it will be used as is, otherwise it
  will be scaled to the range 0 to 255.  (Note that for a PPM, this
  means the largest single rgb component value sets the scale.)

  If the text= keyword is present and non-zero, a text PNM file
  will be written; the default is to write a binary or raw PNM.

  If the noscale=1 keyword is supplied, the IMAGE will not be
  scaled to the range 0 to 255.  In this case, the IMAGE must
  have an integer data type with minimum value >=0.  Note that
  if max(image)>255, a text PGM or PPM file will be written
  (overriding the text= keyword).  Raw PNM is char-only.
  If bits= is not specified, then noscale=1 forces pnm_write to
  guess the value you intended the brightest component value.
  If IMAGE is not color, the guess is bits=1 if there are only
  1 or 2 values, bits=8 if max(IMAGE)<256, and bits=16 otherwise.
  For color IMAGE, the guess is either bits=8 or bits=16.

  Normally, PGM and PPM files have a pixel or color component
  size of 8 bits, so they run from 0 (darkest) to 255 (brightest).
  With bits= you can force a different maximum value.  Use bits=8
  to force a binary IMAGE to be written as a PGM.  The largest
  legal value of bits is 16, the smallest is 1.

SEE ALSO: pnm_colorize, pnm_read