Ubuntu Manpage: pambayer - interpret Bayer patterns

NAME

       pambayer - interpret Bayer patterns

SYNOPSIS

       pambayer -type={1|2|3|4} [-nointerpolate] [pamfile]

       Minimum unique abbreviation of option is acceptable.  You may use double hyphens instead of single hyphen
       to  denote  options.  You may use white space in place of the equals sign to separate an option name from
       its value.

DESCRIPTION

This program is part of Netpbm(1).

pambayer reads a Bayer pattern in a 1-deep Netpbm image and produces a color image in PAM RGB format as
output.

A Bayer pattern is what you get from the optical sensor in some digital cameras. Such a camera doesn't
have a red, green, and blue sensor in the exact same place for an individual pixel. Instead, it has red,
green, and blue sensors laid out in a two dimensional array. The pattern in which they are laid out is
the Bayer pattern. The input to pambayer is one sample value for each of those sensors, so some samples
are red, some are green, and some are blue.

pambayer turns that into a regular visual image with one pixel per sensor. For the two components of
each pixel that are missing in the corresponding Bayer input, pambayer averages the sample values from
the adjacent pixels that do have that component.

But you can have pambayer fill in black instead (see the -noninterpolate option), which gives you a
simpler representation of what the camera saw, on which you might do further processing. Such an image
still looks right, though considerably dimmer, if you stand far enough away and let your eyes do the
interpolation.

The input image is a pseudo-PNM image (pseudo- because while the structure is the same, the sample values
have different meanings) or PAM image of arbitrary tuple type. pambayer looks at only the first plane of
the input.

The output image is a PAM image of tuple type "RGB", i.e. a standard color image. You can convert this
to PPM with pamtopnm(1).

If you're interested in just one of the primary colors, use pamchannel on the output of pambayer to
extract it.

OPTIONS

       In  addition  to  the options common to all programs based on libnetpbm (most notably -quiet, see  Common
       Options ), pambayer recognizes the following command line options:

       -type=n
              This tells which Bayer pattern the input is:

       1      GBG/RGR/GBG matrix

       2      RGR/GBG/RGR matrix

       3      BGB/GRG/BGB matrix

       4      GRG/BGB/GRG matrix

              This option is mandatory.

       -nointerpolate
              Each output pixel position corresponds to one position in the input  Bayer  pattern,  which  means
              only  one  of the three color components is supplied by the input.  For the other two, this option
              says to user zero.  Without it, pambayer instead interpolates from the  adjacent  pixels  that  do
              have that color component.

              This option was new in Netpbm 10.49 (December 2009).

HISTORY

       pambayer was new in Netpbm 10.30 (October 2005).

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