NAME

       TIFFReadDirectory - get the contents of the next directory in an open TIFF file

SYNOPSIS

          #include <tiffio.h>

       int TIFFReadDirectory(TIFF *tif)

DESCRIPTION

       Read  the  next  directory  in  the  specified  file  and  make  it the current directory.
       Applications only need to call TIFFReadDirectory() to read multiple subfiles in  a  single
       TIFF file—(the first directory in a file is automatically read when TIFFOpen() is called.

NOTES

       If  the library is compiled with STRIPCHOP_SUPPORT enabled, then images that have a single
       uncompressed strip or tile of data are automatically treated as if they were  made  up  of
       multiple  strips  or  tiles of approximately 8 kilobytes each. This operation is done only
       in-memory; it does not alter the contents of the file. However, the  construction  of  the
       "chopped  strips"  is  visible  to  the  application  through the number of strips [tiles]
       returned by TIFFNumberOfStrips() [TIFFNumberOfTiles()].

RETURN VALUES

       If the next directory was successfully read, 1 is returned. Otherwise, 0 is returned if an
       error was encountered, or if there are no more directories to be read.

DIAGNOSTICS

       All  error  messages  are  directed  to  the  TIFFErrorExtR()  routine.  Likewise, warning
       messages are directed to the TIFFWarningExtR() routine.

       Seek error accessing TIFF directory:
          An error occurred while positioning to the location of the directory.

       Wrong data type %d for field "%s":
          The tag  entry  in  the  directory  had  an  incorrect  data  type.   For  example,  an
          ImageDescription tag with a SHORT data type.

       TIFF directory is missing required "%s" field:
          The  specified  tag  is  required  to  be present by the TIFF 5.0 specification, but is
          missing.  The directory is (usually) unusable.

       %s: Rational with zero denominator:
          A directory tag has a RATIONAL value whose denominator is zero.

       Incorrect count %d for field "%s" (%lu, expecting %lu); tag ignored:
          The specified tag's count field is bad.  For example,  a  count  other  than  1  for  a
          SubFileType tag.

       Cannot handle different per-sample values for field "%s":
          The  tag has SamplesPerPixel values and they are not all the same; e.g.  BitsPerSample.
          The library is unable to handle images of this sort.

       Count mismatch for field "%s"; expecting %d, got %d:
          The count field in a tag does not agree with the number expected by the  library.  This
          should never happen, so if it does, the library refuses to read the directory.

       Invalid TIFF directory; tags are not sorted in ascending order:
          The  directory tags are not properly sorted as specified in the TIFF 5.0 specification.
          This error is not fatal.

       Ignoring unknown field with tag %d (0x%x):
          An unknown tag was encountered in the directory; the library ignores all such tags.

       TIFF directory is missing required "ImageLength" field:
          The image violates the specification by not having a necessary field.  There is no  way
          for the library to recover from this error.

       TIFF directory is missing required "PlanarConfig" field:
          The  image violates the specification by not having a necessary field.  There is no way
          for the library to recover from this error.

       TIFF directory is missing required "StripOffsets" field:
          The image has multiple strips, but is missing the tag that specifies the file offset to
          each strip of data.  There is no way for the library to recover from this error.

       TIFF directory is missing required "TileOffsets" field:
          The  image has multiple tiles, but is missing the tag that specifies the file offset to
          each tile of data.  There is no way for the library to recover from this error.

       TIFF directory is missing required "StripByteCounts" field:
          The image has multiple strips, but is missing the tag that specifies the size  of  each
          strip of data.  There is no way for the library to recover from this error.

       TIFF directory is missing required "StripByteCounts" field, calculating from imagelength:
          The  image  violates  the specification by not having a necessary field.  However, when
          the image is comprised of only one strip or tile, the library will estimate the missing
          value based on the file size.

       Bogus "StripByteCounts" field, ignoring and calculating from imagelength:
          Certain  vendors  violate the specification by writing zero for the StripByteCounts tag
          when they want to leave the value unspecified.  If the image has a  single  strip,  the
          library will estimate the missing value based on the file size.

SEE ALSO

       TIFFOpen  (3tiff),  TIFFCreateDirectory  (3tiff),  TIFFCustomDirectory  (3tiff), TIFFquery
       (3tiff), TIFFWriteDirectory (3tiff), TIFFSetDirectory (3tiff), Multi Page  /  Multi  Image
       TIFF, libtiff (3tiff)

AUTHOR

       LibTIFF contributors

COPYRIGHT

       1988-2024, LibTIFF contributors