Misc. Reference Manual Pages TIFFGetField(3TIFF)
NAME
TIFFGetField, TIFFVGetField - get the value(s) of a tag in
an open TIFF fileSYNOPSIS
#include
int TIFFGetField(TIFF *tif, ttag_t tag, ...
#include
int TIFFVGetField(TIFF *tif, ttag_t tag, va_list ap
int TIFFGetFieldDefaulted(TIFF *tif, ttag_t tag, ...
int TIFFVGetFieldDefaulted(TIFF *tif, ttag_t tag, va_list ap
DESCRIPTION
TIFFGetField returns the value of a tag or pseudo-tag asso-
ciated with the the current directory of the opened TIFFfile tif. (A pseudo-tag is a parameter that is used to con-
trol 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 with TIFFOpen(3TIFF). The tag is identified by tag, one of the values defined in the include file tiff.h (see also the table below). The type and number of values returned is dependent on the tag beingrequested. The programming interface uses a variable argu-
ment list as prescribed by the stdarg(3) interface. Thereturned values should only be interpreted if TIFFGetField
returns 1.TIFFVGetField is functionally equivalent to TIFFGetField
except that it takes a pointer to a variable argument list. TIFFVGetField is useful for layering interfaces on top ofthe functionality provided by TIFFGetField.
TIFFGetFieldDefaulted and TIFFVGetFieldDefaulted are identi-
cal to TIFFGetField and TIFFVGetField, except that if a tag
is not defined in the current directory and it has a default value, then the default value is returned.The tags understood by libtiff(3TIFF), the number of parame-
ter values, and the types for the returned values are shown below. The data types are specified as in C and correspond to the types used to specify tag values toTIFFSetField(3TIFF). Remember that TIFFGetField returns
parameter values, so all the listed data types are pointers to storage where values should be returned. Consult the TIFF specification (or relevant industry specification) for information on the meaning of each tag and their possible values. libtiff Last change: March 18, 2005 1Misc. Reference Manual Pages TIFFGetField(3TIFF)
Tag Name Count Types NotesTIFFTAG_ARTIST 1 char**
TIFFTAG_BADFAXLINES 1 uint32*
TIFFTAG_BITSPERSAMPLE 1 uint16*
TIFFTAG_CLEANFAXDATA 1 uint16*
TIFFTAG_COLORMAP 3 uint16** 1<
TIFFTAG_COMPRESSION 1 uint16*
TIFFTAG_CONSECUTIVEBADFAXLINES 1 uint32*
TIFFTAG_COPYRIGHT 1 char**
TIFFTAG_DATATYPE 1 uint16*
TIFFTAG_DATETIME 1 char**
TIFFTAG_DOCUMENTNAME 1 char**
TIFFTAG_DOTRANGE 2 uint16*
TIFFTAG_EXTRASAMPLES 2 uint16*,uint16** count & types array
TIFFTAG_FAXFILLFUNC 1 TIFFFaxFillFunc* G3/G4 compression pseudo-tag
TIFFTAG_FAXMODE 1 int* 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_ICCPROFILE 2 uint32*,void** count, profile data
TIFFTAG_IMAGEDEPTH 1 uint32*
TIFFTAG_IMAGEDESCRIPTION 1 char**
TIFFTAG_IMAGELENGTH 1 uint32*
TIFFTAG_IMAGEWIDTH 1 uint32*
TIFFTAG_INKNAMES 1 char**
TIFFTAG_INKSET 1 uint16*
TIFFTAG_JPEGCOLORMODE 1 int* JPEG pseudo-tag
TIFFTAG_JPEGQUALITY 1 int* JPEG pseudo-tag
TIFFTAG_JPEGTABLES 2 uint32*,void** count & tables
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_PHOTOSHOP 2 uint32*,void** count, data
TIFFTAG_PLANARCONFIG 1 uint16*
TIFFTAG_PREDICTOR 1 uint16*
TIFFTAG_PRIMARYCHROMATICITIES 1 float** 6-entry array
TIFFTAG_REFERENCEBLACKWHITE 1 float** 6-entry array
TIFFTAG_RESOLUTIONUNIT 1 uint16*
TIFFTAG_RICHTIFFIPTC 2 uint32*,void** count, data
TIFFTAG_ROWSPERSTRIP 1 uint32*
TIFFTAG_SAMPLEFORMAT 1 uint16*
TIFFTAG_SAMPLESPERPIXEL 1 uint16*
TIFFTAG_SMAXSAMPLEVALUE 1 double*
libtiff Last change: March 18, 2005 2Misc. Reference Manual Pages TIFFGetField(3TIFF)
TIFFTAG_SMINSAMPLEVALUE 1 double*
TIFFTAG_SOFTWARE 1 char**
TIFFTAG_STONITS 1 double**
TIFFTAG_STRIPBYTECOUNTS 1 uint32**
TIFFTAG_STRIPOFFSETS 1 uint32**
TIFFTAG_SUBFILETYPE 1 uint32*
TIFFTAG_SUBIFD 2 uint16*,uint32** count & offsets array
TIFFTAG_TARGETPRINTER 1 char**
TIFFTAG_THRESHHOLDING 1 uint16*
TIFFTAG_TILEBYTECOUNTS 1 uint32**
TIFFTAG_TILEDEPTH 1 uint32*
TIFFTAG_TILELENGTH 1 uint32*
TIFFTAG_TILEOFFSETS 1 uint32**
TIFFTAG_TILEWIDTH 1 uint32*
TIFFTAG_TRANSFERFUNCTION 1 or 3|- uint16**1<
TIFFTAG_WHITEPOINT 1 float** 2-entry array
TIFFTAG_XMLPACKET 2 uint32*,void** count, data
TIFFTAG_XPOSITION 1 float*
TIFFTAG_XRESOLUTION 1 float*
TIFFTAG_YCBCRCOEFFICIENTS 1 float** 3-entry array
TIFFTAG_YCBCRPOSITIONING 1 uint16*
TIFFTAG_YCBCRSUBSAMPLING 2 uint16*
TIFFTAG_YPOSITION 1 float*
TIFFTAG_YRESOLUTION 1 float*|=
|- If SamplesPerPixel is one, then a single array is
returned; otherwise three arrays are returned. |= The contents of this field are quite complex. See The ICCProfile Format Specification, Annex B.3 "Embedding ICC Pro-
files in TIFF Files" (available at http://www.color.org) for an explanation. AUTOREGISTERED TAGS If you can't find the tag in the table above that means this is unsupported tag. But you still be able to read it's value if you know the data type of that tag. For example, if you want to read the LONG value from the tag 33424 and ASCII string from the tag 36867 you can use the following code: uint16 count; void *data;TIFFGetField(tiff, 33424, &count, &data);
printf("Tag %d: %d, count %d0, 33424, *(uint32 *)data, count);
TIFFGetField(tiff, 36867, &count, &data);
printf("Tag %d: %s, count %d0, 36867, (char *)data, count);
is not supported by libtiff(3TIFF), libraryRETURN VALUES
1 is returned if the tag is defined in the current direc-
tory; otherwise a 0 is returned. libtiff Last change: March 18, 2005 3Misc. Reference Manual Pages TIFFGetField(3TIFF)
DIAGNOSTICSAll error messages are directed to the TIFFError(3TIFF) rou-
tine.Unknown field, tag 0x%x. An unknown tag was supplied.
SEE ALSO
TIFFOpen(3TIFF), TIFFSetField(3TIFF), TIFFSetDirectory(3TIFF), TIFFReadDirectory(3TIFF), TIFFWriteDirectory(3TIFF) libtiff(3TIFF), Libtiff library home page: http://www.remotesensing.org/libtiff/ libtiff Last change: March 18, 2005 4