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  ⟨index.html#commonoptions⟩  ), 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).

DOCUMENT SOURCE