TIFFWriteScanline(3TIFF)												  TIFFWriteScanline(3TIFF)

NAME

       TIFFWriteScanline - write a scanline to an open TIFF file

SYNOPSIS

       #include <tiffio.h>

       int TIFFWriteScanline(TIFF *tif, tdata_t buf, uint32 row, tsample_t sample)

DESCRIPTION

       Write  data  to	a  file at the specified row. The sample parameter is used only if data are organized in separate planes (PlanarConfigura-
       tion=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). 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 StripByte-
       Counts fields are similarly enlarged to reflect data written past the previous end of image.

NOTES

       The library writes encoded data using the native machine byte order. Correctly implemented TIFF readers are expected to	do  any  necessary
       byte-swapping  to  correctly  process  image  data with BitsPerSample greater than 8. The library attempts to hide bit-ordering differences
       between the image and the native machine by converting data from the native machine order.

       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(3TIFF) 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.

RETURN VALUES

       TIFFWriteScanline returns -1 if it immediately detects an error and 1 for a successful write.

DIAGNOSTICS

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

       %s: File not open for writing .	The file was opened for reading, not writing.

       Can not write scanlines to a tiled image.  An attempt was made to write a scanline to a tiled image. The image is assumed to  be  organized
       in tiles because the TileWidth and TileLength tags have been set with TIFFSetField(3TIFF).

       Compression  algorithm  does not support random access.	Data was written in a non-sequential order to a file that uses a compression algo-
       rithm 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 as entire
       strips, sequentially by rows, or the value of RowsPerStrip should be set to one.

       %s: Must set "ImageWidth" before writing data.  The image's width has not be set before	the  first  write.   See  TIFFSetField(3TIFF)  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 TIFFSet-
       Field(3TIFF) 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.

       %s: No space for strip arrays .	There was not enough space for the arrays that hold strip offsets and byte counts.

BUGS

       Writing subsampled YCbCR data does not work correctly because, for PlanarConfiguration=2 the size of a scanline is not calculated on a per-
       sample basis, and for PlanarConfiguration=1 the library does not pack the block-interleaved samples.

SEE ALSO

       TIFFOpen(3TIFF), TIFFWriteEncodedStrip(3TIFF), TIFFWriteRawStrip(3TIFF), libtiff(3TIFF)

       Libtiff library home page: http://www.remotesensing.org/libtiff/

libtiff 							 December 16, 1991					  TIFFWriteScanline(3TIFF)