NAME

       TIFFFieldQuery - routines to query TIFF field information

SYNOPSIS

          #include <tiffio.h>

       const TIFFField *TIFFFieldWithName(TIFF *tif, const char *field_name)

       const TIFFField *TIFFFieldWithTag(TIFF *tif, uint32_t tag)

       const TIFFField *TIFFFindField(TIFF *tif, uint32_t tag, TIFFDataType dt)

       int TIFFFieldIsAnonymous(const TIFFField *fip)

       int TIFFFieldSetGetSize(const TIFFField *fip)

       int TIFFFieldSetGetCountSize(const TIFFField *fip)

DESCRIPTION

       TIFFFieldWithName()  and  TIFFFieldWithTag()  return a pointer to TIFF field information structure fip by
       the tag's field_name or its tag number.

       TIFFFindField() searches for the TIFF field information structure  fip  of  a  given  tag  number  and  a
       specific TIFFDataType dt.  With dt== TIFF_ANY the behaviour is the same than for TIFFFieldWithTag().
          Such  a  TIFFDataType  dependent  search  could  be useful when the same tag is defined twice but with
          different data types, which is true for rare cases like TIFFTAG_XCLIPPATHUNITS. However,  the  libtiff
          does currently not support multiple definitions of the same tag.

       The following routines return status information about TIFF fields.
          fip  is  a  field  information  pointer  previously  returned  by TIFFFindField(), TIFFFieldWithTag(),
          TIFFFieldWithName().

       TIFFFieldIsAnonymous() returns true (nonzero) if the field, read from file, is unknown to libtiff  and  a
       anonymous  field has been auto-registered. Return is zero "0" if field is known to libtiff.  See  Default
       Tag Auto-registration   for more information.

       TIFFFieldSetGetSize() returns the data size in bytes of the field data type  used  for  libtiff  internal
       storage.   This  is  also  the  data  size  of  the  parameter  to  be  provided  to  TIFFSetField()  and
       TIFFGetField(). Custom TIFF_RATIONAL  values  can  be  stored  internally  either  as  float  or  double.
       TIFFFieldSetGetSize() would then return "4" or "8", respectively.

       TIFFFieldSetGetCountSize()  returns size of count parameter of TIFFSetField() and TIFFGetField() and also
       if it is required:  0=none, 2= uint16_t, 4= uint32_t

DIAGNOSTICS

       None.

SEE ALSO

       libtiff (3tiff)

AUTHOR

       LibTIFF contributors

COPYRIGHT

       1988-2024, LibTIFF contributors

4.5                                               Sep 05, 2024                             TIFFFIELDQUERY(3tiff)