Pamundice User Manual(1) General Commands Manual Pamundice User Manual(1)
NAME
pamundice - combine grid of images (tiles) into one
EXAMPLE
$ pamdice myimage.ppm -outstem=myimage_part -width=10 -height=8
$ pamundice myimage_part_%1d_%1a.ppm -across=10 -down=8 >myimage.ppm
$ pamundice myimage.ppm myimage_part_%2a -across=13 -hoverlap=9
SYNOPSIS
pamundice
[-across=n]
[-down=n]
[-hoverlap=pixels]
[-voverlap=pixels]
[-verbose]
{input_filename_pattern, -listfile=filename}
You can use the minimum unique abbreviation of the options. You can
use two hyphens instead of one. You can separate an option name from
its value with white space instead of an equals sign.
DESCRIPTION
This program is part of Netpbm(1).
pamundice reads a bunch of Netpbm images as input and combines them as
a grid of tiles into a single output image of the same kind on Standard
Output.
You can optionally make the pieces overlap.
The images can either be in files whose names indicate where they go in
the
output (e.g. 'myimage_part_03_04' could be the image for Row 3,
Column 4 - see the input_filename_pattern argument) or listed in a
file, with a -listfile option.
The input images must all have the same format (PAM, PPM, etc.) and
maxval and for PAM must have the same depth and tuple type. All the
images in a rank (horizontal row of tiles) must have the same height.
All the images in a file (vertical column of tiles) must have the same
width. But it is not required that every rank have the same height or
every file have the same width.
pamdice is the inverse of pamundice. You can use pamundice to reassem-
ble an image sliced up by pamdice. You can use pamdice to recreate the
tiles of an image created by pamundice, but to do this, the original
ranks must all have been the same height except for the bottom one and
the original files must all have been the same width except the right
one.
One use for this is to process an image in pieces when the whole image
is too large to process. For example, you might have an image so large
that an image editor can't read it all into memory or processes it very
slowly. You can split it into smaller pieces with pamdice, edit one at
a time, and then reassemble them with pamundice.
Of course, you can also use pamundice to compose various kinds of
checkerboard images, for example, you could write a program to render a
chessboard by computing an image of each square, then using pamundice
to assemble them into a board.
An alternative to join images in a single direction (i.e. a single rank
or a single file) is pnmcat. pnmcat gives you more flexibility than
pamundice in identifying the input images: you can supply them on Stan-
dard Input or as a list of arbitrarily named files.
To join piecewise photographs, use pnmstitch instead of pamundice, be-
cause it figures out where the pieces overlap, even if they don't over-
lap exactly vertically or horizontally.
To create an image of the same tile repeated in a grid, that's pnmtile.
pnmindex does a similar thing to pamundice: it combines a bunch of
small images in a grid into a big one. But its purpose is to produce a
an index image of the input images. So it leaves space between them
and has labels for them, for example.
ARGUMENTS
Unless you use a -listfile option,, there is one non-option argument,
and it is mandatory: input_filename_pattern. This tells pamundice what
files contain the input tiles.
pamundice reads the input images from files which are named with a pat-
tern that indicates their positions in the combined image. For exam-
ple, tile_00_05.ppm could be the 6th tile over in the 1st rank, while
tile_04_01 is the 2nd tile over in the 5th rank.
You cannot supply any of the data on Standard Input, and the files must
be the kind that pamundice can close and reopen and read the same image
a second time (e.g. a regular file is fine; a named pipe is probably
not).
input_filename_pattern is a printf-style pattern. (See the standard C
library printf subroutine). For the example above, it would be
tile_%2d_%2a.ppm. The only possible conversion specifiers are:
d "down": The rank (row) number, starting with 0.
a "across": The file (column) number, starting with 0.
% The per cent character (%).
The number between the % and the conversion specifier is the precision
and is required. It says how many characters of the file name are de-
scribed by that conversion. The rank or file number is filled with
leading zeroes as necessary.
So the example tile_%2d_%2a.ppm means to get the name of the file that
contains the tile at Rank 0, File 5, you:
• replace the "%2d" with the rank number, as a 2 digit decimal
number: "00"
• Replace the "%2a" with the file number, as a 2 digit decimal
number: "05"
Note that this pattern describes file names that pamdice produces, ex-
cept that the precision may be more or less. (pamdice uses however
many digits are required for the highest numbered image).
OPTIONS
In addition to the options common to all programs based on libnetpbm
(most notably -quiet, see
Common Options ⟨index.html#commonoptions⟩ ), pamundice recognizes the
following command line options:
-across=N
This is the number of tiles across in the grid, i.e. the number
of tiles in each rank, or the number of files.
Default is 1.
-down=N
This is the number of tiles up and down in the grid, i.e. the
number of tiles in each file, or the number of ranks.
Default is 1.
-hoverlap=pixels
This is the amount in pixels to overlap the tiles horizontally.
pamundice clips this much off the right edge of every tile be-
fore joining it to the adjacent image to the right. The tiles
along the right edge remain whole.
There must not be any input image narrower than this.
Note that this undoes the effect of the same -hoverlap option of
pamdice.
Default is zero -- no overlap.
-voverlap=pixels
This is analogous to -hoverlap, but pamundice clips the bottom
edge of each image before joining it to the one below.
-listfile=filename
This option names a file that contains the names of all the in-
put files. This is an alternative to specifying a file name
pattern as an argument.
The named file contains file name, one per line. Each file con-
tains the
image for one tile, in row-major order, top to bottom, left to
right. So
the first file is the upper left tile, the second is the one
to right of
that, etc. The number of lines in the file must be equal to
the number of
tiles in the output, the product of the -across and -down
values.
The file names have no meaning to pamundice. You can use the
same
file multiple times to have identical tiles in the output.
This option was new in Netpbm 10.90 (March 2020).
-verbose
Print information about the processing to Standard Error.
HISTORY
pamundice was new in Netpbm 10.39 (June 2007). Before that, pnmcat is
the best substitute.
SEE ALSO
pamdice(1), pnmcat(1), pnmindex(1), pnmtile(1), pnm(1) pam(1)
DOCUMENT SOURCE
This manual page was generated by the Netpbm tool 'makeman' from HTML
source. The master documentation is at
http://netpbm.sourceforge.net/doc/pamundice.html
netpbm documentation 26 April 2020 Pamundice User Manual(1)
Generated by dwww version 1.15 on Sat Jun 29 02:32:13 CEST 2024.