Ubuntu Manpage: tiffmakemosaic - splits one or more TIFF file into mosaic(s) (set(s)

Provided by: largetifftools_1.3.10-2_amd64

NAME

         tiffmakemosaic - splits one or more TIFF file into mosaic(s) (set(s)
       of TIFF or JPEG files smaller than a chosen size that would reproduce
       the original file if glued together)

USAGE

         tiffmakemosaic [options] file1.tif [file2.tif...]

DESCRIPTION

       tiffmakemosaic takes one or more single-image TIFF files and creates, for each one of these, a mosaic (if
       needed). A mosaic is a set of TIFF files that would reproduce the original image if glued together  (e.g.
       with  ImageMagick  or  GraphicsMagick's  montage command). Unless an explicit dimension is requested, all
       pieces of a mosaic have the same width and length and these dimensions are submultiples of  the  original
       image's  dimensions.  They  are  chosen  so  that  each piece of the mosaic is smaller than a given size.
       Therefore, even if the original image is huge and wouldn't fit into the computer's memory, which prevents
       it to be opened by most software, the pieces will be small enough to be opened easily.

       A mosaic is produced as soon as the full provided image doesn't meet the requirements of needed memory to
       open (option -M below), width, or size (option -g below).

       If requested, it will add some overlap to the adjacent pieces (either of a fixed amount of pixels, or  of
       a  percentage  of  the  pieces'  width  resp.   length,  will appear on two pieces if they share a common
       border).

       The names given to the output files that contain the pieces are created by  adding  the  row  and  column
       numbers of the piece after the name of the original image and before the extension.

PERFORMANCES

       In  principle,  generating  pieces  from  a  large  TIFF file can also be achieved with several tools, as
       tiffcrop, ImageMagick and GraphicsMagick (one has to first compute and specify explicitly the  dimensions
       and  positions  of  the pieces, though). However, most of the programs start with opening and deciphering
       the whole image either in memory or in a huge temporary file on the disk, which makes  them  quite  slow,
       and often unable to complete the task by lack of memory.

       In  contrast,  tiffmakemosaic  avoids  opening  the  whole  image,  which  yields  speedup and guarantees
       successful termination of the process even on computers with modest memory. Eg. to make a  mosaic  of  64
       JPEG  files  requesting less than 512 MiB of memory to open from a RGB image of 103168x63232 pixels, on a
       computer with 16 GiB of RAM and an i5 CPU, tiffmakemosaic needs 2.5 minutes while GraphicsMagick needs 70
       minutes.

OPTIONS

-v Verbose monitoring.

-T Do not report TIFF errors or warnings. Under Windows, they are reported with noisy dialog boxes.

-M <size in MiB>
Dimensions of the pieces of each mosaic will be computed so that no more than the specified amount
of memory will be required to open one of them. Defaults to 1024 MiB = 1 GiB = 1073741824 bytes. A
value of zero means no limit on the dimensions to achieve a goal of memory requirement (but there
may be other limits, e.g. the installed memory in the computer during production of the mosaic).

-m [width divisor in pixels]x[length divisor in pixels]
If either dimension is provided, the pieces of the mosaic will be integer multiples of this
dimension. If a divisor is zero or is not provided, this option adds no constrain on the
corresponding piece dimension.

For instance, -m 8x0 will require that the width of the pieces be a multiple of 8 pixels.

-g [width in pixels]x[length in pixels]
If either dimension is provided, the pieces of the mosaic will have exactly this dimension
(ignoring the -m option if present), except perhaps for the last piece of each row or the last
piece of each column if the dimension is not an exact divisor of the corresponding dimension of
the full image. If a dimension is zero or is not provided, it is replaced with the largest value
which is compatible with the memory limit (option -M) and divides the corresponding full image
dimension by a power of two.

For example, -M 2048 -g x200 will require pieces of length exactly 200 pixels (but the pieces in
the last row at the bottom of the image may be shorter) and width equal to W/2^n where W is the
width of the full image and 2^n is the largest integer power of 2 such that a piece of size W/2^n
x 200 pixels requires less than 2048 MiB of memory to open.

-O <number of pixels | fraction%>
The adjacent pieces will overlap by that amount: if the border of a piece is not on a outer border
of the full image, then the piece will be extended in the corresponding direction by the requested
amount. If the amount is given in percent (a decimal number between 0 and 100 included, followed
by the `%' symbol), the overlap amount will be the corresponding fraction of the piece's width (if
overlapping across a vertical border) resp. length (horizontal border). Horizontal and vertical
overlaps can be different. If the amount is given as a number of pixels (must be a nonnegative
decimal integer number), the overlap amount will be the specified amount, disregarding the actual
dimensions of the pieces. However, the overlap will be truncated down to a piece's width resp.
length if it would be larger.

By default, produced mosaics have no overlap.

-j[#] Requests output of JPEG files rather than the default TIFF. Optional number # in the range 0 to
100 indicates wanted JPEG quality (default is 75).

If several of -j and -c options are given, only the last one takes effect.

-c <method>[:opt[:opt]...]
Requests output of TIFF files compressed with method. Method can be `none' for no compression,
`jpeg', `lzw', `zip'... as provided by the LibTIFF library (see libtiff (3TIFF)). By default, the
same compression as in the input TIFF file is used.

Method-specific details of the wished compression can be specified by adding one or several group
of characters starting with a colon `:' after the methods's name, as follows.

JPEG method:
:# set compression quality level as in option -j (see above).

LZW, Deflate (zip) and LZMA2 options:
:# set predictor value
:p# set compression level.

For example, -c lzw:2 to get LZW-encoded data with horizontal differencing, -c zip:3:p9 for
Deflate encoding with maximum compression level and floating point predictor, -c jpeg:r:50 for
JPEG-encoded RGB data at quality 50%.