Provided by: libtiff-tools_4.5.0-5ubuntu1_amd64 
NAME
fax2tiff - create a TIFF Class F fax file from raw fax data
SYNOPSIS
fax2tiff [ options ] [ -o output.tif ] input.raw
DESCRIPTION
fax2tiff creates a TIFF file containing CCITT Group 3 or Group 4 encoded data from one or
more files containing "raw" Group 3 or Group 4 encoded data (typically obtained directly
from a fax modem). By default, each row of data in the resultant TIFF file is
1-dimensionally encoded and padded or truncated to 1728 pixels, as needed. The resultant
image is a set of low resolution (98 lines/inch) or medium resolution (196 lines/inch)
pages, each of which is a single strip of data. The generated file conforms to the TIFF
Class F (FAX) specification for storing facsimile data. This means, in particular, that
each page of the data does not include the trailing "return to control" (RTC) code; as
required for transmission by the CCITT Group 3 specifications. The old, "classic", format
is created if the -c option is used. (The Class F format can also be requested with the
-f option.)
The default name of the output image is fax.tif; this can be changed with the -o option.
Each input file is assumed to be a separate page of facsimile data from the same document.
The order in which input files are specified on the command line is the order in which the
resultant pages appear in the output file.
OPTIONS
Options that affect the interpretation of input data are:
-3 Assume input data is CCITT Group 3 encoded (default).
-4 Assume input data is CCITT Group 4 encoded.
-U Assume input data is uncompressed (Group 3 or Group 4).
-1 Assume input data is encoded with the 1-dimensional version of the CCITT Group 3
Huffman encoding algorithm (default).
-2 Assume input data is 2-dimensional version of the CCITT Group 3 Huffman encoding
algorithm.
-P Assume input data is not EOL-aligned (default). This option has effect with Group 3
encoded input only.
-A Assume input data is EOL-aligned. This option has effect with Group 3 encoded input
only.
-M Treat input data as having bits filled from most significant bit (MSB) to most
least bit (LSB).
-L Treat input data as having bits filled from least significant bit (LSB) to most
significant bit (MSB) (default).
-B Assume input data was encoded with black as 0 and white as 1.
-W Assume input data was encoded with black as 1 and white as 0 (default).
-R Specify the vertical resolution, in lines/inch, of the input images. By default
input are assumed to have a vertical resolution of 196 lines/inch. If images are
low resolution facsimile, a value of 98 lines/inch should be specified.
-X Specify the width, in pixels, of the input images. By default input are assumed to
have a width of 1728 pixels.
Options that affect the output file format are:
-o Specify the name of the output file.
-7 Force output to be compressed with the CCITT Group 3 Huffman encoding algorithm
(default).
-8 Force output to be compressed with the CCITT Group 4 Huffman encoding.
-u Force output to be uncompressed (Group 3 or Group 4).
-5 Force output to be encoded with the 1-dimensional version of the CCITT Group 3
Huffman encoding algorithm.
-6 Force output to be encoded with the 2-dimensional version of the CCITT Group 3
Huffman encoding algorithm (default).
-a Force the last bit of each "End Of Line" (EOL) code to land on a byte boundary
(default). This "zero padding" will be reflected in the contents of the
Group3Options tag of the resultant TIFF file. This option has effect with Group 3
encoded output only.
-p Do not EOL-align output. This option has effect with Group 3 encoded output only.
-c Generate "classic" Group 3 TIFF format.
-f Generate TIFF Class F (TIFF/F) format (default).
-m Force output data to have bits filled from most significant bit (MSB) to most least
bit (LSB).
-l Force output data to have bits filled from least significant bit (LSB) to most
significant bit (MSB) (default).
-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), tiffcp attempts to set the
rows/strip that no more than 8 kilobytes of data appear in a strip (with except of
G3/G4 compression schemes). If you specify 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. This is default in case of G3/G4 output compression schemes.
-s Stretch the input image vertically by writing each input row of data twice to the
output file.
-v Force fax2tiff to print the number of rows of data it retrieved from the input
file.
-z Force output to be compressed with the LZW encoding.
DIAGNOSTICS
The following warnings and errors come from the decoding routines in the library.
"Warning, %s: Premature EOL at scanline %d (x %d).en":
The input data had a row that was shorter than the expected width. The row is padded
with white.
"%s: Premature EOF at scanline %d (x %d).en":
The decoder ran out of data in the middle of a scanline. The resultant row is padded
with white.
"%s: Bad code word at row %d, x %den":
An invalid Group 3 code was encountered while decoding the input file. The row number
and horizontal position is given. The remainder of the input row is discarded, while
the corresponding output row is padded with white.
"%s: Bad 2D code word at scanline %d.en":
An invalid Group 4 or 2D Group 3 code was encountered while decoding the input file.
The row number and horizontal position is given. The remainder of the input row is
discarded, while the corresponding output row is padded with white.
BUGS
Input data are assumed to have a a "top left" orientation; it should be possible to
override this assumption from the command line.
SEE ALSO
"CCITT Recommendation T.4" (Standardization of Group 3 Facsimile Apparatus for Document
Transmission).
"The Spirit of TIFF Class F", an appendix to the TIFF 5.0 specification prepared by Cygnet
Technologies.
tiffinfo (1), tiffdither (1), tiffgt (1), libtiff (3tiff)
AUTHOR
LibTIFF contributors
COPYRIGHT
1988-2023, LibTIFF contributors