Ubuntu Manpage: pcompos - composite RADIANCE pictures.

Provided by: radiance_4R1+20120125-1.1_amd64

NAME

       pcompos - composite RADIANCE pictures.

SYNOPSIS

       pcompos  [  -h ][ -x xres ][ -y yres ][ -b r g b ][ -lh h ][ -la ] [ -t min1 ][ +t max1 ][
       -l lab ][ =SS ] pic1 x1 y1 ..
       or
       pcompos [ -a ncols ][ -s spacing ][ -o x0 y0 ][ options ] pic1 pic2 ..

DESCRIPTION

Pcompos arranges and composites RADIANCE pictures and sends the result to the standard
output. Each input picture must be accompanied by an anchor point (unless the -a option
is used, see below). This anchor point is the usually position of the picture's left
lower corner in the final output, but can be changed for individual pictures with an =SS
option, where S is one of '-', '+' or '0', indicating the minimum, maximum or center of
the image, respectively. (For example, =+- would indicate the anchor is relative to the
right lower corner, and =-0 would indicate the anchor is relative to the center of the
left edge.) Negative anchor coordinates result in the input being cropped at the origin.
By default, the size of the output picture will be just large enough to encompass all the
input files. By specifying a smaller dimension using the -x and -y options, input files
can be cropped at the upper boundary. Specifying a larger dimension produces a border.
The -b option specifies a background color to appear wherever input files do not cover.
The default value is black (0 0 0). The -h option may be used to reduce the information
header size, which can grow disproportionately after multiple runs of pcompos and/or
pcomb(1).

If input files overlap, later pictures will overwrite earlier ones. By default, input
files are copied unconditionally within the output boundaries. The -t option specifies a
lower threshold intensity under which input pixels will not be copied to the output. The
+t option specifies an upper threshold. These options are useful for cutting around
irregular boundaries in the input.

The -l option can be used to specify a label for a specific picture, which will be given a
height determined by the -lh option (default 24 pixels) and placed in the upper left
corner of the picture. This label is generated by the program psign(1). The -la option
instructs pcompos to label each picture automatically by its name. This is particularly
useful in conjunction with the -a option for producing a catalog of images (see example
below). The -l option may still be used to override the default label for a picture.

The -a option can be used to automatically compute anchor points that place successive
pictures next to each other in ncols columns. The ordering will place the first picture
in the lower left corner, the next just to the right of it, and so on for ncols pictures.
Then, the next row up repeats the pattern until all the input pictures have been added to
the output. If the pictures are of different size, pcompos will end up leaving some
background areas in the output picture. There will also be an unfinished row at the top
if the number of pictures is not evenly divided by ncols. The -s N option will cause each
image to be separated by at least N pixels. The -o x0 y0 option specifies a nonzero
anchor point for the bottom left image.

The standard input can be specified with a hyphen ('-'). A command that produces a
RADIANCE picture can be given in place of a file by preceeding it with an exclamation
point ('!').

EXAMPLE

       To put a copyright label at the bottom of a picture:

         psign Copyright 1987 | pcompos inp.hdr 0 0 +t .5 - 384 64 > out.hdr

       To make a catalog of images separated by white 10-pixel borders:

         pcompos -la -a 4 -s 10 -b 1 1 1 dog*.hdr > alldogs.hdr

NOTES

       Since  there  is  a  limit to the number of open files and processes, large collections of
       images must be created in stages.  Even if the  system  limit  on  open  files  is  large,
       pcompos places an artificial limit of 1024 on the number of open files and/or processes.

AUTHOR