TIFFSetField(3T)

NAME

TIFFSetField - set the value(s) of a tag in a TIFF file open for writing

SYNOPSIS

#include <tiffio.h>
int TIFFSetField(TIFF* tif, ttag_t tag, ...)
#include <stdarg.h>
int TIFFVSetField(TIFF* tif, ttag_t tag, va_list ap)

DESCRIPTION

TIFFSetField sets the value of a field or pseudo-tag in the current directory associated with the open TIFF file tif. (A pseudo-tag is a parameter that is used to control the operation of the TIFF library but whose value is not read or written to the underlying file.) The file must have been previously opened for writing with TIFFOpen(3T). The field is identified by tag, one of the values defined in the include file tiff.h (see also the table below). The actual value is specified using a variable argument list, as prescribed by the stdarg(3) interface (or, on some machines, the varargs(3) interface.)

TIFFVSetField is functionally equivalent to TIFFSetField except that it takes a pointer to a variable argument list. TIFFVSetField is useful for writing routines that are layered on top of the functionality provided by TIFFSetField.

The tags understood by libtiff, the number of parameter values, and the expected types for the parameter values are shown below. The data types are: char* is null-terminated string and corresponds to the ASCII data type; uint16 is an unsigned 16-bit value; uint32 is an unsigned 32-bit value; uint16* is an array of unsigned 16-bit values. void* is an array of data values of unspecified type.

Consult the TIFF specification for information on the meaning of each tag.

     Tag Name                        Count  Types              Notes
     TIFFTAG_ARTIST                  1      char*
     TIFFTAG_BADFAXLINES             1      uint32
     TIFFTAG_BITSPERSAMPLE           1      uint16             -
     TIFFTAG_CLEANFAXDATA            1      uint16
     TIFFTAG_COLORMAP                3      uint16*            1<<BitsPerSample arrays
     TIFFTAG_COMPRESSION             1      uint16             -
     TIFFTAG_CONSECUTIVEBADFAXLINES  1      uint32
     TIFFTAG_DATETIME                1      char*
     TIFFTAG_DOCUMENTNAME            1      char*
     TIFFTAG_DOTRANGE                2      uint16
     TIFFTAG_EXTRASAMPLES            2      uint16,uint16*     - count & types array
     TIFFTAG_FAXMODE                 1      int                - G3/G4 compression pseudo-tag
     TIFFTAG_FAXFILLFUNC             1      TIFFFaxFillFunc    G3/G4 compression pseudo-tag
     TIFFTAG_FILLORDER               1      uint16             -
     TIFFTAG_GROUP3OPTIONS           1      uint32             -
     TIFFTAG_GROUP4OPTIONS           1      uint32             -
     TIFFTAG_HALFTONEHINTS           2      uint16
     TIFFTAG_HOSTCOMPUTER            1      char*
     TIFFTAG_IMAGEDESCRIPTION        1      char*
     TIFFTAG_IMAGEDEPTH              1      uint32             -
     TIFFTAG_IMAGELENGTH             1      uint32
     TIFFTAG_IMAGEWIDTH              1      uint32             -
     TIFFTAG_INKNAMES                1      char*
     TIFFTAG_INKSET                  1      uint16             -
     TIFFTAG_JPEGTABLES              2      uint32*,void*      - count & tables
     TIFFTAG_JPEGQUALITY             1      int                JPEG pseudo-tag
     TIFFTAG_JPEGCOLORMODE           1      int                - JPEG pseudo-tag
     TIFFTAG_JPEGTABLESMODE          1      int                - JPEG pseudo-tag
     TIFFTAG_MAKE                    1      char*
     TIFFTAG_MATTEING                1      uint16             -
     TIFFTAG_MAXSAMPLEVALUE          1      uint16
     TIFFTAG_MINSAMPLEVALUE          1      uint16
     TIFFTAG_MODEL                   1      char*
     TIFFTAG_ORIENTATION             1      uint16
     TIFFTAG_PAGENAME                1      char*
     TIFFTAG_PAGENUMBER              2      uint16
     TIFFTAG_PHOTOMETRIC             1      uint16
     TIFFTAG_PLANARCONFIG            1      uint16             -
     TIFFTAG_PREDICTOR               1      uint16             -
     TIFFTAG_PRIMARYCHROMATICITIES   1      float              6-entry array
     TIFFTAG_REFERENCEBLACKWHITE     1      float*             - 2*SamplesPerPixel array
     TIFFTAG_RESOLUTIONUNIT          1      uint16
     TIFFTAG_ROWSPERSTRIP            1      uint32             - must be > 0
     TIFFTAG_SAMPLEFORMAT            1      uint16             -
     TIFFTAG_SAMPLESPERPIXEL         1      uint16             - value must be <= 4
     TIFFTAG_SMAXSAMPLEVALUE         1      double
     TIFFTAG_SMINSAMPLEVALUE         1      double
     TIFFTAG_SOFTWARE                1      char*
     TIFFTAG_SUBFILETYPE             1      uint32
     TIFFTAG_SUBIFD                  2      uint16,uint32*     count & offsets array
     TIFFTAG_TARGETPRINTER           1      char*
     TIFFTAG_THRESHHOLDING           1      uint16
     TIFFTAG_TILEDEPTH               1      uint32             -
     TIFFTAG_TILELENGTH              1      uint32             - must be a multiple of 8
     TIFFTAG_TILEWIDTH               1      uint32             - must be a multiple of 8
     TIFFTAG_TRANSFERFUNCTION        1 or 3 |                  uint16*1<<BitsPerSample entry arrays
     TIFFTAG_XPOSITION               1      float
     TIFFTAG_XRESOLUTION             1      float
     TIFFTAG_WHITEPOINT              1      float              2-entry array
     TIFFTAG_YCBCRCOEFFICIENTS       1      float*             - 3-entry array
     TIFFTAG_YCBCRPOSITIONING        1      uint16             -
     TIFFTAG_YCBCRSAMPLING           2      uint16             -
     TIFFTAG_YPOSITION               1      float
     TIFFTAG_YRESOLUTION             1      float
     TIFFTAG_ICCPROFILE              2      uint32,void*       count, profile data*
* The contents of this field are quite complex. See The ICC Profile Format Specification, Annex B.3 "Embedding ICC Profiles in TIFF Files" (available at http://www.color.org) for an explanation.

RETURN VALUES

1 is returned if the tag is defined in the current directory; otherwise a 0 is returned.

RETURN VALUES

1 is returned if the operation was successful. Otherwise, 0 is returned if an error was detected.

DIAGNOSTICS

All error messages are directed to the TIFFError(3T) routine.

%s: Cannot modify tag "%s" while writing. Data has already been written to the file, so the specified tag's value can not be changed. This restriction is applied to all tags that affect the format of written data.

%d: Bad value for "%s". An invalid value was supplied for the named tag.

SEE ALSO

libtiff(3T), TIFFOpen(3T), TIFFGetField(3T), TIFFSetDirectory(3T), TIFFWriteDirectory(3T), TIFFReadDirectory(3T)