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TIFFSETFIELD(3tiff) LibTIFF TIFFSETFIELD(3tiff)
NAME
TIFFSetField - set the value(s) of a tag in a TIFF file open for
writing
SYNOPSIS
#include <tiffio.h>
#include <stdarg.h>"
int TIFFSetField(TIFF *tif, ttag_t tag, ...)
int TIFFVSetField(TIFF *tif, ttag_t tag, va_list ap)
int TIFFUnsetField(TIFF *tif, uint32_t tag)
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.) To set the
value of a field the file must have been previously opened for writing
with TIFFOpen(). Pseudo-tags can be set whether the file was opened
for reading or writing. 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.h 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().
TIFFUnsetField() clears the contents of the field in the internal
structure. If it is a custom field, it is removed from the list of
known tags.
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:
TAG DATA TYPES
+----------+----------------------------+
|Type | Description |
+----------+----------------------------+
|char* | a null-terminated string |
| | corresponding to the ASCII |
| | data type |
+----------+----------------------------+
|uint16_t | an unsigned 16-bit value |
+----------+----------------------------+
|uint32_t | an unsigned 32-bit value; |
+----------+----------------------------+
|uint16_t* | an array of unsigned |
| | 16-bit values. |
+----------+----------------------------+
|void* | an array of data values of |
+-------------------------------+------------+------------------+------------------+
|Tag name | Count | Types | Notes |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_ARTIST | 1 | char* | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_BADFAXLINES | 1 | uint32_t | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_BITSPERSAMPLE | 1 | uint16_t | <*> |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_CLEANFAXDATA | 1 | uint16_t | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_COLORMAP | 3 | uint16_t* | 1 << |
| | | | BitsPerSample |
| | | | arrays |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_COMPRESSION | 1 | uint16_t | <*> |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_CONSECUTIVEBADFAXLINES | 1 | uint32_t | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_COPYRIGHT | 1 | char* | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_DATETIME | 1 | char* | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_DOCUMENTNAME | 1 | char* | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_DOTRANGE | 2 | uint16_t | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_EXTRASAMPLES | 2 | uint16_t, | <*> count, types |
| | | uint16_t* | 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 | char* | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_ICCPROFILE | 2 | uint32_t, void* | count, profile |
| | | | data* |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_IMAGEDEPTH | 1 | uint32_t | <*> |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_IMAGEDESCRIPTION | 1 | char* | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_IMAGELENGTH | 1 | uint32_t | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_IMAGEWIDTH | 1 | uint32_t | <*> |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_JPEGQUALITY | 1 | int | JPEG pseudo-tag |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_JPEGTABLES | 2 | uint32_t*, void* | <*> count, |
| | | | tables |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_JPEGTABLESMODE | 1 | int | <*> JPEG |
| | | | pseudo-tag |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_MAKE | 1 | char* | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_MATTEING | 1 | uint16_t | <*> |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_MAXSAMPLEVALUE | 1 | uint16_t | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_MINSAMPLEVALUE | 1 | uint16_t | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_MODEL | 1 | char* | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_ORIENTATION | 1 | uint16_t | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_PAGENAME | 1 | char* | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_PAGENUMBER | 2 | uint16_t | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_PHOTOMETRIC | 1 | uint16_t | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_PHOTOSHOP | ? | uint32_t, void* | count, data |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_PLANARCONFIG | 1 | uint16_t | <*> |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_PREDICTOR | 1 | uint16_t | <*> |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_PRIMARYCHROMATICITIES | 1 | float* | 6-entry array |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_REFERENCEBLACKWHITE | 1 | float* | <*> 6-entry |
| | | | array |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_RESOLUTIONUNIT | 1 | uint16_t | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_RICHTIFFIPTC | 2 | uint32_t, void* | count, data |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_ROWSPERSTRIP | 1 | uint32_t | <*> must be > 0 |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_SAMPLEFORMAT | 1 | uint16_t | <*> |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_SAMPLESPERPIXEL | 1 | uint16_t | <*> value must |
| | | | be <= 4 |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_SMAXSAMPLEVALUE | 1 | double | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_SMINSAMPLEVALUE | 1 | double | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_SOFTWARE | 1 | char* | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_STONITS | 1 | double | <*> |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_SUBFILETYPE | 1 | uint32_t | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_TILEDEPTH | 1 | uint32_t | <*> |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_TILELENGTH | 1 | uint32_t | <*> must be a |
| | | | multiple of 8 |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_TILEWIDTH | 1 | uint32_t | <*> must be a |
| | | | multiple of 8 |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_TRANSFERFUNCTION | 1 or 3<**> | uint16_t* | 1 << |
| | | | BitsPerSample |
| | | | entry arrays |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_WHITEPOINT | 1 | float* | 2-entry array |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_XMLPACKET | 2 | uint32_t, void* | count, data |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_XPOSITION | 1 | float | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_XRESOLUTION | 1 | float | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_YCBCRCOEFFICIENTS | 1 | float* | <*> 3-entry |
| | | | array |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_YCBCRPOSITIONING | 1 | uint16_t | <*> |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_YCBCRSAMPLING | 2 | uint16_t | <*> |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_YPOSITION | 1 | float | |
+-------------------------------+------------+------------------+------------------+
|TIFFTAG_YRESOLUTION | 1 | float | |
+-------------------------------+------------+------------------+------------------+
<*>: Tag may not have its values changed once data is written.
<**>:
If SamplesPerPixel is one, then a single array is passed; otherwise
three arrays should be passed.
*: 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 operation was successful. Otherwise, 0 is
returned if an error was detected.
DIAGNOSTICS
All error messages are directed to the TIFFErrorExtR() 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
1988-2022, LibTIFF contributors
4.6 September 8, 2023 TIFFSETFIELD(3tiff)