NAME
tiffcrop - select, copy, crop, convert, extract, and/or process one or
more TIFF files.
SYNOPSIS
tiffcrop [ options ] src1.tif ... srcN.tif dst.tif
DESCRIPTION
Tiffcrop processes one or more files created according to the Tag Image
File Format, Revision 6.0, specification into one or more TIFF file(s).
Tiffcrop is most often used to extract portions of an image for
processing with bar code recognizer or OCR software when that software
cannot restrict the region of interest to a specific portion of the
image or to improve efficiency when the regions of interest must be
rotated. It can also be used to subdivide all or part of a processed
image into smaller sections and export individual images or sections of
images as separate files or separate images within one or more files
derived from the original input image or images.
The available functions can be grouped broadly into three classes:
Those that select individual images or sections of images from
the input files. The options -N for sequences or lists of
individual images in the input files, -Z for zones, -z for
regions, -X and -Y for fixed sized selections, -m for margins,
-U for units, and -E for edge reference provide a variety of
ways to specify portions of the input image.
Those that allow the individual images or selections to be
exported to one or more output files in different groupings and
control the organization of the data in the output images. The
options -P for page size grouping, -S for subdivision into
columns and rows and -e for export mode options that produce one
or more files from each input image. The options -r, -s, -t, -w
control strip and tile format and sizes while -B -L -c -f modify
the endian addressing scheme, the compression options, and the
bit fill sequence of images as they are written.
Those that perform some action on each image that is selected
from the input file. The options include -R for rotate, -I for
inversion of the photometric interpretation and/or data values,
and -F to flip (mirror) the image horizontally or vertically.
Functions are applied to the input image(s) in the following order:
cropping, fixed area extraction, zone and region extraction, inversion,
mirroring, rotation.
Functions are applied to the output image(s) in the following order:
export mode options for grouping zones, regions, or images into one or
more files, or row and column divisions with output margins, or page
size divisions with page orientation options.
Finally, strip, tile, byte order, output resolution, and compression
options are applied to all output images.
The output file(s) may be organized and compressed using a different
algorithm from the input files. By default, tiffcrop will copy all the
understood tags in a TIFF directory of an input file to the associated
directory in the output file. Options can be used to force the
resultant image to be written as strips or tiles of data, respectively.
Tiffcrop can be used to reorganize the storage characteristics of data
in a file, and to reorganize, extract, rotate, and otherwise process
the image data as specified at the same time whereas tiffcp does not
alter the image data within the file.
Using the options for selecting individual input images and the options
for exporting images and/or segments defined as zones or regions of
each input image, tiffcrop can perform the functions of tiffcp and
tiffsplit in a single pass while applying multiple operations to
individual selections or images.
OPTIONS
-h Display the syntax summary for tiffcrop.
-v Report the current version and last modification date for
tiffcrop.
-N odd|even|#,#-#,#|last
Specify one or more series or range(s) of images within each
file to process. The words odd or even may be used to specify
all odd or even numbered images counting from one. Note that
internally, TIFF images are numbered from zero rather than one
but since this convention is not obvious to most users, tiffcrop
used 1 to specifiy the first image in a multipage file. The
word last may be used in place of a number in the sequence to
indicate the final image in the file without knowing how many
images there are. Ranges of images may be specified with a dash
and multiple sets can be indicated by joining them in a
comma-separated list. eg. use -N 1,5-7,last to process the 1st,
5th through 7th, and final image in the file.
-E top|bottom|left|right
Specify the top, bottom, left, or right edge as the reference
from which to calcuate the width and length of crop regions or
sequence of postions for zones. When used with the -e option for
exporting zones or regions, the reference edge determines how
composite images are arranged. Using -E left or right causes
successive zones or regions to be merged horizontally whereas
using -E top or bottom causes successive zones or regions to be
arranged vertically. This option has no effect on export layout
when multiple zones or regions are not being exported to
composite images. Edges may be abbreviated to the first letter.
-e combined|divided|image|multiple|separate
Specify the export mode for images and selections from input
images. The final filename on the command line is considered to
be the destination file or filename stem for automatically
generated sequences of files. Modes may be abbreviated to the
first letter.
combined All images and selections are written to a single
file with multiple selections from one image combined into a
single image (default)
divided All images and selections are written to a single
file with each selection from one image written to a new image
image Each input image is written to a new file (numeric
filename sequence) with multiple selections from the image
combined into one image
multiple Each input image is written to a new file (numeric
filename sequence) with each selection from the image written to
a new image
separate Individual selections from each image are written to
separate files
-U in|cm|px
Specify the type of units to apply to dimensions for margins and
crop regions for input and output images. Inches or centimeters
are converted to pixels using the resolution unit specified in
the TIFF file (which defaults to inches if not specified in the
IFD).
-m #,#,#,#
Specify margins to be removed from the input image. The order
must be top, left, bottom, right with only commas separating the
elements of the list. Margins are scaled according to the
current units and removed before any other extractions are
computed..
-X # Set the horizontal (X-axis) dimension of a region to extract
relative to the specified origin reference. If the origin is the
top or bottom edge, the X axis value will be assumed to start at
the left edge.
-Y # Set the vertical (Y-axis) dimension of a region to extract
relative to the specified origin reference. If the origin is the
left or right edge, the Y axis value will be assumed to start at
the top.
-Z #:#,#:#
Specify zones of the image designated as position X of Y equal
sized portions measured from the reference edge, eg 1:3 would
be first third of the image starting from the reference edge
minus any margins specified for the confining edges. Multiple
zones can be specified as a comma separated list but they must
reference the same edge. To extract the top quarter and the
bottom third of an image you would use -Z 1:4,3:3.
-z x1,y1,x2,y2: ... :xN,yN,xN+1,yN+1
Specify a series of coordinates to define regions for processing
and exporting. The coordinates represent the top left and lower
right corners of each region in the current units, eg inch, cm,
or pixels. Pixels are counted from one to width or height and
inches or cm are calculated from image resolution data.
Each colon delimited series of four values represents the
horizontal and vertical offsets from the top and left edges of
the image, regardless of the edge specified with the -E option.
The first and third values represent the horizontal offsets of
the corner points from the left edge while the second and fourth
values represent the vertical offsets from the top edge.
-F horiz|vert
Flip, ie mirror, the image or extracted region horizontally or
vertically.
-R 90|180|270
Rotate the image or extracted region 90, 180, or 270 degrees
clockwise.
-I [black|white|data|both]
Invert color space, eg dark to light for bilevel and grayscale
images. This can be used to modify negative images to positive
or to correct images that have the PHOTOMETRIC_INTERPRETATIN tag
set incorrectly. If the value is black or white, the
PHOTOMETRIC_INTERPRETATION tag is set to MinIsBlack or
MinIsWhite, without altering the image data. If the argument is
data or both, the data values of the image are modified.
Specifying both inverts the data and the
PHOTOMETRIC_INTERPRETATION tag, whereas using data inverts the
data but not the PHOTOMETRIC_INTERPRETATION tag. No support for
modifying the color space of color images in this release.
-H # Set the horizontal resolution of output images to # expressed in
the current units.
-V # Set the vertical resolution of the output images to # expressed
in the current units.
-J # Set the horizontal margin of an output page size to # expressed
in the current units when sectioning image into columns x rows
subimages using the -S cols:rows option.
-K # Set the vertical margin of an output page size to # expressed in
the current units when sectioning image into columns x rows
submiages using the -S cols:rows option.
-O portrait|landscape|auto
Set the output orientation of the pages or sections. Auto will
use the arrangement that requires the fewest pages. This option
is only meaningful in conjunction with the -P option to format
an image to fit on a specific paper size.
-P page
Format the output images to fit on page size paper. Use -P list
to show the supported page sizes and dimensions. You can define
a custom page size by entering the width and length of the page
in the current units with the following format #.#x#.#.
-S cols:rows
Divide each image into cols across and rows down equal sections.
-B Force output to be written with Big-Endian byte order. This
option only has an effect when the output file is created or
overwritten and not when it is appended to.
-C Suppress the use of ``strip chopping'' when reading images that
have a single strip/tile of uncompressed data.
-c Specify the compression to use for data written to the output
file: none for no compression, packbits for PackBits
compression, lzw for Lempel-Ziv & Welch compression, jpeg for
baseline JPEG compression. zip for Deflate compression, g3 for
CCITT Group 3 (T.4) compression, and g4 for CCITT Group 4 (T.6)
compression. By default tiffcrop will compress data according
to the value of the Compression tag found in the source file.
The CCITT Group 3 and Group 4 compression algorithms can only be
used with bilevel data.
Group 3 compression can be specified together with several
T.4-specific options: 1d for 1-dimensional encoding, 2d for
2-dimensional encoding, and fill to force each encoded scanline
to be zero-filled so that the terminating EOL code lies on a
byte boundary. Group 3-specific options are specified by
appending a ``:''-separated list to the ``g3'' option; e.g. -c
g3:2d:fill to get 2D-encoded data with byte-aligned EOL codes.
LZW compression can be specified together with a predictor
value. A predictor value of 2 causes each scanline of the
output image to undergo horizontal differencing before it is
encoded; a value of 1 forces each scanline to be encoded without
differencing. LZW-specific options are specified by appending a
``:''-separated list to the ``lzw'' option; e.g. -c lzw:2 for
LZW compression with horizontal differencing.
-f Specify the bit fill order to use in writing output data. By
default, tiffcrop will create a new file with the same fill
order as the original. Specifying -f lsb2msb will force data to
be written with the FillOrder tag set to LSB2MSB, while -f
msb2lsb will force data to be written with the FillOrder tag set
to MSB2LSB.
-i Ignore non-fatal read errors and continue processing of the
input file.
-l Specify the length of a tile (in pixels). Tiffcrop attempts to
set the tile dimensions so that no more than 8 kilobytes of data
appear in a tile.
-L Force output to be written with Little-Endian byte order. This
option only has an effect when the output file is created or
overwritten and not when it is appended to.
-M Suppress the use of memory-mapped files when reading images.
-p Specify the planar configuration to use in writing image data
that has more than one sample per pixel. By default, tiffcrop
will create a new file with the same planar configuration as the
original. Specifying -p contig will force data to be written
with multi-sample data packed together, while -p separate will
force samples to be written in separate planes.
-r Specify the number of rows (scanlines) in each strip of data
written to the output file. By default (or when value 0 is
specified), tiffcrop attempts to set the rows/strip that no more
than 8 kilobytes of data appear in a strip. If you specify the
special value -1 it will results in infinite number of the rows
per strip. The entire image will be the one strip in that case.
-s Force the output file to be written with data organized in
strips (rather than tiles).
-t Force the output file to be written with data organized in tiles
(rather than strips).
-w Specify the width of a tile (in pixels). tiffcrop attempts to
set the tile dimensions so that no more than 8 kilobytes of data
appear in a tile. tiffcrop attempts to set the tile dimensions
so that no more than 8 kilobytes of data appear in a tile.
Debug and dump facility
-D opt1:value1,opt2:value2,opt3:value3:opt4:value4 Display
program progress and/or dump raw data to non-TIFF files.
Options include the following and must be joined as a comma
separated list. The use of this option is generally limited to
program debugging and development of future options. An equal
sign may be substituted for the colon in option:value pairs.
debug:N Display limited program progress indicators
where larger N increase the level of detail.
format:txt|raw Format any logged data as ASCII text or raw
binary values. ASCII text dumps include strings of ones and
zeroes representing the binary values in the image data plus
identifying headers.
level:N Specify the level of detail presented in the
dump files. This can vary from dumps of the entire input or
output image data to dumps of data processed by specific
functions. Current range of levels is 1 to 3.
input:full-path-to-directory/input-dumpname
output:full-path-to-directory/output-dumpname
When dump files are being written, each image will be written to
a separate file with the name built by adding a numeric sequence
value to the dumpname and an extension of .txt for ASCII dumps
or .bin for binary dumps.
The four debug/dump options are independent, though it makes
little sense to specify a dump file without specifying a detail
level.
Note: Tiffcrop may be compiled with -DDEVELMODE to enable
additional very
low level debug reporting.
EXAMPLES
The following concatenates two files and writes the result using LZW
encoding:
tiffcrop -c lzw a.tif b.tif result.tif
To convert a G3 1d-encoded TIFF to a single strip of G4-encoded data
the following might be used:
tiffcrop -c g4 -r 10000 g3.tif g4.tif
(1000 is just a number that is larger than the number of rows in the
source file.)
To extract a selected set of images from a multi-image TIFF file use
the -N option described above. Thus, to copy the 1st and 3rd images of
image file "album.tif" to "result.tif":
tiffcrop -N 1,3 album.tif result.tif
Invert a bilevel image scan of a microfilmed document and crop off
margins of 0.25 inches on the left and right, 0.5 inch on the top, and
0.75 inch on the bottom. From the remaining portion of the image,
select the second and third quarters, ie, one half of the area left
from the center to each margin.
tiffcrop -U in -m 0.5,0.25,0.75,0.25 -E left -Z 2:4,3:4 -I both
MicrofilmNegative.tif MicrofilmPostiveCenter.tif
Extract only the final image of a large Architectural E sized multipage
TIFF file and rotate it 90 degrees clockwise while reformatting the
output to fit on tabloid sized sheets with one quarter of an inch on
each side:
tiffcrop -N last -R 90 -O auto -P tabloid -U in -J 0.25 -K 0.25
-H 300 -V 300 Big-PlatMap.tif BigPlatMap-Tabloid.tif
The output images will have a specified resolution of 300 dpi in both
directions. The orientation of each page will be determined by
whichever choice requires the fewest pages. To specify a specific
orientation, use the portrait or landscape option. The paper size
option does not resample the image. It breaks each original image into
a series of smaller images that will fit on the target paper size at
the specified resolution.
Extract two regions 2048 pixels wide by 2048 pixels high from each page
of a multi-page input file and write each region to a separate output
file.
tiffcrop -U px -z 1,1,2048,2048:1,2049,2048,4097 -e separate
CheckScans.tiff Check
The output file names will use the stem Check with a numeric suffix
which is incremented for each region of each image, eg Check-001.tiff,
Check-002.tiff ... Check-NNN.tiff. To produce a unique file for each
page of the input image with one new image for each region of the input
image on that page, change the export option to -e multiple.
NOTES
In general, bilevel, grayscale, palette and RGB(A) data with bit depths
from 1 to 32 bits should work in both interleaved and separate plane
formats. Unlike tiffcp, tiffcrop can read and write tiled images with
bits per sample that are not a multiple of 8 in both interleaved and
separate planar format. Floating point data types are supported at bit
depts of 16, 24, 32 and 64 bits per sample.
Not all images can be converted from one compression scheme to another.
Data with some photometric interpretations and/or bit depths are tied
to specific compression schemes and vice-versa, e.g. Group 3/4
compression is only usable for bilevel data. JPEG compression is only
useable on 8 bit per sample data (or 12 bit if LibTIFF was compiled
with 12 bit JPEG support). Support for OJPEG compressed images is
problematic at best. Since OJPEG compression is no longer supported for
writing images with LibTIFF, these images will be updated to the newer
JPEG compression when they are copied or processed. This may cause the
image to appear color shifted or distorted after conversion. In some
cases, it is possible to remove the original compression from image
data using the option -cnone.
Tiffcrop does not currently provide options to up or downsample data to
different bit depths or convert data from one photometric
interpretation to another, e.g. 16 bits per sample to 8 bits per sample
or RGB to grayscale.
Tiffcrop is very loosely derived from code in tiffcp with extensive
modifications and additions to support the selection of input images
and regions and the exporting of them to one or more output files in
various groupings. The image manipulation routines are entirely new and
additional ones may be added in the future. It will handle tiled images
with bit depths that are not a multiple of eight that tiffcp may refuse
to read.
Tiffcrop was designed to handle large files containing many moderate
sized images with memory usage that is independent of the number of
images in the file. In order to support compression modes that are not
based on individual scanlines, e.g. JPEG, it now reads images by strip
or tile rather than by indvidual scanlines. In addition to the memory
required by the input and output buffers associated with LibTIFF one or
more buffers at least as large as the largest image to be read are
required. The design favors large volume document processing uses over
scientific or graphical manipulation of large datasets as might be
found in research or remote sensing scenarios.
SEE ALSO
pal2rgb(1), tiffinfo(1), tiffcmp(1), tiffcp(1), tiffmedian(1),
tiffsplit(1), libtiff(3TIFF)
Libtiff library home page: http://www.remotesensing.org/libtiff/