# pamundice - combine grid of images (tiles) into one - man(1) - [phpMan]

> **TLDR:** Combine a grid of Netpbm images into one.
>
- Combine the images whose names match the `printf`-style filename expression. Assume a grid with a specific size:
  `pamundice {{filename_%1d_%1a.ppm}} {{-a|-across}} {{grid_width}} {{-d|-down}} {{grid_height}} > {{path/to/output.ppm}}`
- Assume that the tiles overlap horizontally and vertically by the specified amount:
  `pamundice {{filename_%1d_%1a.ppm}} {{-a|-across}} {{x_value}} {{-d|-down}} {{y_value}} {{-ho|-hoverlap}} {{value}} {{-vo|-voverlap}} {{value}} > {{path/to/output.ppm}}`
- Specify the images to be combined through a text file containing one filename per line:
  `pamundice {{-l|-listfile}} {{path/to/file.txt}} {{-a|-across}} {{x_value}} {{-d|-down}} {{y_value}} > {{path/to/output.ppm}}`

*Source: tldr-pages*

---

_Pamundice_ _User_ [_Manual_(1)](https://www.chedong.com/phpMan.php/man/Manual/1/markdown)               General Commands Manual              _Pamundice_ _User_ [_Manual_(1)](https://www.chedong.com/phpMan.php/man/Manual/1/markdown)

## 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)](https://www.chedong.com/phpMan.php/man/Netpbm/1/markdown).

       **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 reassemble 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
       **pamcat**.  **pamcat **gives you more flexibility than **pamundice **in identifying  the  input  images:
       you can supply them on Standard Input or as a list of arbitrarily named files.

       To  join  piecewise  photographs,  use **pnmstitch **instead of **pamundice**, because it figures out
       where the pieces overlap, even if they don't overlap 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 pattern that indicates
       their positions in the combined image.  For example, **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 **pa‐**
       **mundice **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 **subrou‐
       tine).   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 described 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, except 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=_
              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=_
              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=_
              This  is the amount in pixels to overlap the tiles horizontally.  **pamundice **clips this
              much off the right edge of every tile before 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=_
              This  is analogous to **-hoverlap**, but **pamundice **clips the bottom edge of each image be‐
              fore joining it to the one below.


### -listfile=_
              This option names a file that contains the names of all the input 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 contains 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, **pamcat **is the best substitute.



## SEE ALSO
       [**pamdice**(1)](https://www.chedong.com/phpMan.php/man/pamdice/1/markdown), [**pamcat**(1)](https://www.chedong.com/phpMan.php/man/pamcat/1/markdown), [**pnmindex**(1)](https://www.chedong.com/phpMan.php/man/pnmindex/1/markdown), [**pnmtile**(1)](https://www.chedong.com/phpMan.php/man/pnmtile/1/markdown), [**pnm**(1)](https://www.chedong.com/phpMan.php/man/pnm/1/markdown) [**pam**(1)](https://www.chedong.com/phpMan.php/man/pam/1/markdown)

## 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)](https://www.chedong.com/phpMan.php/man/Manual/1/markdown)
