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%.