TIFFGetField¶
Synopsis¶
#include <tiffio.h>
#include <stdarg.h>
-
int TIFFGetField(TIFF *tif, ttag_t tag, ...)¶
-
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 associated with the
the current directory of the opened 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 with TIFFOpen()
. 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 being requested. The programming
interface uses a variable argument list as prescribed by the stdarg.h
interface. The returned 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 of the functionality provided by
TIFFGetField()
.
TIFFGetFieldDefaulted()
and TIFFVGetFieldDefaulted()
are identical
to TIFFGetField()
and TIFFVGetField()
, respectively, 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 the number of parameter 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 to
TIFFSetField()
. 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.
¶ Tag name
Count
Types
Notes
TIFFTAG_ARTIST
1
const char**
TIFFTAG_BADFAXLINES
1
uint32_t*
TIFFTAG_BITSPERSAMPLE
1
uint16_t*
TIFFTAG_CLEANFAXDATA
1
uint16_t*
TIFFTAG_COLORMAP
3
const uint16_t**
1 << BitsPerSample arrays
TIFFTAG_COMPRESSION
1
uint16_t*
TIFFTAG_CONSECUTIVEBADFAXLINES
1
uint32_t*
TIFFTAG_COPYRIGHT
1
const char**
TIFFTAG_DATATYPE
1
uint16_t*
TIFFTAG_DATETIME
1
const char**
TIFFTAG_DOCUMENTNAME
1
const char**
TIFFTAG_DOTRANGE
2
uint16_t*
TIFFTAG_EXTRASAMPLES
2
uint16_t*, const uint16_t**
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_t*
TIFFTAG_GROUP3OPTIONS
1
uint32_t*
TIFFTAG_GROUP4OPTIONS
1
uint32_t*
TIFFTAG_HALFTONEHINTS
2
uint16_t*
TIFFTAG_HOSTCOMPUTER
1
const char**
TIFFTAG_ICCPROFILE
2
const uint32_t*, const void**
count, profile data‡
TIFFTAG_IMAGEDEPTH
1
uint32_t*
TIFFTAG_IMAGEDESCRIPTION
1
const char**
TIFFTAG_IMAGELENGTH
1
uint32_t*
TIFFTAG_IMAGEWIDTH
1
uint32_t*
TIFFTAG_INKNAMES
1
const char**
TIFFTAG_INKSET
1
uint16_t*
TIFFTAG_JPEGCOLORMODE
1
int*
JPEG pseudo-tag
TIFFTAG_JPEGQUALITY
1
int*
JPEG pseudo-tag
TIFFTAG_JPEGTABLES
2
uint32_t*, const void**
count, tables
TIFFTAG_JPEGTABLESMODE
1
int*
JPEG pseudo-tag
TIFFTAG_MAKE
1
const char**
TIFFTAG_MATTEING
1
uint16_t*
TIFFTAG_MAXSAMPLEVALUE
1
uint16_t*
TIFFTAG_MINSAMPLEVALUE
1
uint16_t*
TIFFTAG_MODEL
1
const char**
TIFFTAG_ORIENTATION
1
uint16_t*
TIFFTAG_PAGENAME
1
const char**
TIFFTAG_PAGENUMBER
2
uint16_t*
TIFFTAG_PHOTOMETRIC
1
uint16_t*
TIFFTAG_PHOTOSHOP
2
uint32_t*, const void**
count, data
TIFFTAG_PLANARCONFIG
1
uint16_t*
TIFFTAG_PREDICTOR
1
uint16_t*
TIFFTAG_PRIMARYCHROMATICITIES
1
const float**
6-entry array
TIFFTAG_REFERENCEBLACKWHITE
1
const float**
6-entry array
TIFFTAG_RESOLUTIONUNIT
1
uint16_t*
TIFFTAG_RICHTIFFIPTC
2
uint32_t*, const void**
count, data
TIFFTAG_ROWSPERSTRIP
1
uint32_t*
TIFFTAG_SAMPLEFORMAT
1
uint16_t*
TIFFTAG_SAMPLESPERPIXEL
1
uint16_t*
TIFFTAG_SMAXSAMPLEVALUE
1
double*
TIFFTAG_SMINSAMPLEVALUE
1
double*
TIFFTAG_SOFTWARE
1
const char**
TIFFTAG_STONITS
1
double*
TIFFTAG_STRIPBYTECOUNTS
1
const uint64_t**
TIFFTAG_STRIPOFFSETS
1
const uint64_t**
TIFFTAG_SUBFILETYPE
1
uint32_t*
TIFFTAG_SUBIFD
2
uint16_t*, const uint64_t**
count, offsets array
TIFFTAG_TARGETPRINTER
1
const char**
TIFFTAG_THRESHHOLDING
1
uint16_t*
TIFFTAG_TILEBYTECOUNTS
1
const uint64_t**
TIFFTAG_TILEDEPTH
1
uint32_t*
TIFFTAG_TILELENGTH
1
uint32_t*
TIFFTAG_TILEOFFSETS
1
const uint64_t**
TIFFTAG_TILEWIDTH
1
uint32_t*
TIFFTAG_TRANSFERFUNCTION
1 or 3†
const uint16_t**
1 << BitsPerSample entry arrays
TIFFTAG_WHITEPOINT
1
const float**
2-entry array
TIFFTAG_XMLPACKET
2
uint32_t*, const void**
count, data
TIFFTAG_XPOSITION
1
float*
TIFFTAG_XRESOLUTION
1
float*
TIFFTAG_YCBCRCOEFFICIENTS
1
const float**
3-entry array
TIFFTAG_YCBCRPOSITIONING
1
uint16_t*
TIFFTAG_YCBCRSUBSAMPLING
2
uint16_t*
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 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.
Diagnostics¶
All error messages are directed to the TIFFErrorExtR()
routine.
Unknown field, tag 0x%x
:
An unknown tag was supplied.
See also¶
TIFFOpen (3tiff), TIFFSetField (3tiff), TIFFSetDirectory (3tiff), TIFFReadDirectory (3tiff), TIFFWriteDirectory (3tiff), libtiff (3tiff)