TIFFWriteScanline(3T)     UNIX System V(May 2, 1990)      TIFFWriteScanline(3T)


NAME
      TIFFWriteScanline - write a scanline to an open TIFF file

SYNOPSIS
      #include <tiffio.h>
      int TIFFWriteScanline(TIFF* tif, uchar* buf, uint row, uint sample)

DESCRIPTION
      Write data to a file at the specified row.  The sample parameter is used
      only if data are organized in separate planes (PlanarConfiguration=2).
      The data are assumed to be uncompressed and in the native bit- and byte-
      order of the host machine.  The data written to the file is compressed
      according to the compression scheme of the current TIFF directory (see
      further below).  TIFFWriteScanline returns -1 if it immediately detects
      an error and 1 for a successful write.  If the current scanline is past
      the end of the current subfile, the ImageLength field is automatically
      increased to include the scanline (except for PlanarConfiguration=2,
      where the ImageLength cannot be changed once the first data are written).
      If the ImageLength is increased, the StripOffsets and StripByteCounts
      fields are similarly enlarged to reflect data written past the previous
      end of image.

NOTES
      The library attempts to hide bit- and byte-ordering differences between
      the image and the native machine by converting data from the native
      machine order.  Bit reversal is always done if the FillOrder tag is
      opposite to the native machine bit order.  Byte swapping of 16- and 32-
      bit samples is automatically done when Compression=1 (``no
      compression''), but otherwise is left to the compression algorithms
      (which should generate compressed data in the native byte ordering of the
      machine).

      In C++ the sample parameter defaults to 0.

      Once data are written to a file for the current directory, the values of
      certain tags may not be altered; see TIFFSetField(3T) for more
      information.

      It is not possible to write scanlines to a file that uses a tiled
      organization.  The routine TIFFIsTiled() can be used to determine if the
      file is organized as tiles or strips.

DIAGNOSTICS
      All error messages are directed to the TIFFError(3T) routine.

      Compression algorithm does not support random access.  Data was written
      in a non-sequential order to a file that uses a compression algorithm and
      that has RowsPerStrip greater than one.  That is, data in the image is to
      be stored in a compressed form, and with multiple rows packed into a
      strip.  In this case, the library does not support random access to the
      data.  The data should either be written sequentially, or the value of
      RowsPerStrip should be set to one.


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TIFFWriteScanline(3T)     UNIX System V(May 2, 1990)      TIFFWriteScanline(3T)


      %s: Must set "ImageWidth" before writing data.  The image's width has not
      be set before the first write.  See TIFFSetField(3T) for information on
      how to do this.

      %s: Must set "PlanarConfiguration" before writing data.  The organization
      of data has not be defined before the first write.  See TIFFSetField(3T)
      for information on how to do this.

      Can not change "ImageLength" when using separate planes.  Separate image
      planes are being used (PlanarConfiguration=2), but the number of rows has
      not been specified before the first write.  The library supports the
      dynamic growth of an image only when data are organized in a contiguous
      manner (PlanarConfiguration=1).

      %d: Sample out of range, max %d, The sample parameter was greater than
      the value of the SamplesPerPixel tag.

      Can not write scanlines to a tiled image.  An attempt was made to write a
      scanline to a tiled image.  The library does not support this.

SEE ALSO
      intro(3T), TIFFOpen(3T), TIFFWriteEncodedStrip(3T), TIFFWriteRawStrip(3T)
































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