<!-- Creator : groff version 1.18.1 -->
<!-- CreationDate: Sat Feb 24 18:37:18 2007 -->
<html>
<head>
<meta name="generator" content="groff -Thtml, see www.gnu.org">
<meta name="Content-Style" content="text/css">
<title>TIFFWriteScanline</title>
</head>
<body>
<h1 align=center>TIFFWriteScanline</h1>
<a href="#NAME">NAME</a><br>
<a href="#SYNOPSIS">SYNOPSIS</a><br>
<a href="#DESCRIPTION">DESCRIPTION</a><br>
<a href="#NOTES">NOTES</a><br>
<a href="#RETURN VALUES">RETURN VALUES</a><br>
<a href="#DIAGNOSTICS">DIAGNOSTICS</a><br>
<a href="#BUGS">BUGS</a><br>
<a href="#SEE ALSO">SEE ALSO</a><br>
<hr>
<a name="NAME"></a>
<h2>NAME</h2>
<!-- INDENTATION -->
<table width="100%" border=0 rules="none" frame="void"
cols="2" cellspacing="0" cellpadding="0">
<tr valign="top" align="left">
<td width="8%"></td>
<td width="91%">
<p>TIFFWriteScanline − write a scanline to an open
<small>TIFF</small> file</p>
</td>
</table>
<a name="SYNOPSIS"></a>
<h2>SYNOPSIS</h2>
<!-- INDENTATION -->
<table width="100%" border=0 rules="none" frame="void"
cols="2" cellspacing="0" cellpadding="0">
<tr valign="top" align="left">
<td width="8%"></td>
<td width="91%">
<p><b>#include <tiffio.h></b></p>
<!-- INDENTATION -->
<p><b>int TIFFWriteScanline(TIFF *</b><i>tif</i><b>,
tdata_t</b> <i>buf</i><b>, uint32</b> <i>row</i><b>,
tsample_t</b> <i>sample</i><b>)</b></p>
</td>
</table>
<a name="DESCRIPTION"></a>
<h2>DESCRIPTION</h2>
<!-- INDENTATION -->
<table width="100%" border=0 rules="none" frame="void"
cols="2" cellspacing="0" cellpadding="0">
<tr valign="top" align="left">
<td width="8%"></td>
<td width="91%">
<p>Write data to a file at the specified row. The
<i>sample</i> parameter is used only if data are organized
in separate planes (<i>PlanarConfiguration</i>=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 <small>TIFF</small> directory (see further below).
If the current scanline is past the end of the current
subfile, the <i>ImageLength</i> field is automatically
increased to include the scanline (except for
<i>PlanarConfiguration</i>=2, where the <i>ImageLength</i>
cannot be changed once the first data are written). If the
<i>ImageLength</i> is increased, the <i>StripOffsets</i> and
<i>StripByteCounts</i> fields are similarly enlarged to
reflect data written past the previous end of image.</p>
</td>
</table>
<a name="NOTES"></a>
<h2>NOTES</h2>
<!-- INDENTATION -->
<table width="100%" border=0 rules="none" frame="void"
cols="2" cellspacing="0" cellpadding="0">
<tr valign="top" align="left">
<td width="8%"></td>
<td width="91%">
<p>The library writes encoded data using the native machine
byte order. Correctly implemented <small>TIFF</small>
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.</p>
<!-- INDENTATION -->
<p>In C++ the <i>sample</i> parameter defaults to 0.</p>
<!-- INDENTATION -->
<p>Once data are written to a file for the current
directory, the values of certain tags may not be altered;
see <i>TIFFSetField</i>(3TIFF) for more information.</p>
<!-- INDENTATION -->
<p>It is not possible to write scanlines to a file that uses
a tiled organization. The routine <i>TIFFIsTiled</i> can be
used to determine if the file is organized as tiles or
strips.</p>
</td>
</table>
<a name="RETURN VALUES"></a>
<h2>RETURN VALUES</h2>
<!-- INDENTATION -->
<table width="100%" border=0 rules="none" frame="void"
cols="2" cellspacing="0" cellpadding="0">
<tr valign="top" align="left">
<td width="8%"></td>
<td width="91%">
<p><i>TIFFWriteScanline</i> returns −1 if it
immediately detects an error and 1 for a successful
write.</p>
</td>
</table>
<a name="DIAGNOSTICS"></a>
<h2>DIAGNOSTICS</h2>
<!-- INDENTATION -->
<table width="100%" border=0 rules="none" frame="void"
cols="2" cellspacing="0" cellpadding="0">
<tr valign="top" align="left">
<td width="8%"></td>
<td width="91%">
<p>All error messages are directed to the
<i>TIFFError</i>(3TIFF) routine.</p>
<!-- INDENTATION -->
<p><b>%s: File not open for writing .</b> The file was
opened for reading, not writing.</p>
<!-- INDENTATION -->
<p><b>Can not write scanlines to a tiled image</b>. An
attempt was made to write a scanline to a tiled image. The
image is assumed to be organized in tiles because the
<i>TileWidth</i> and <i>TileLength</i> tags have been set
with <i>TIFFSetField</i>(3TIFF).</p>
<!-- INDENTATION -->
<p><b>Compression algorithm does not support random
access</b>. Data was written in a non-sequential order to a
file that uses a compression algorithm and that has
<i>RowsPerStrip</i> 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 <i>RowsPerStrip</i> should be set to one.</p>
<!-- INDENTATION -->
<p><b>%s: Must set "ImageWidth" before writing
data</b>. The image’s width has not be set before the
first write. See <b>TIFFSetField</b>(3TIFF) for information
on how to do this.</p>
<!-- INDENTATION -->
<p><b>%s: Must set "PlanarConfiguration" before
writing data</b>. The organization of data has not be
defined before the first write. See
<b>TIFFSetField</b>(3TIFF) for information on how to do
this.</p>
<!-- INDENTATION -->
<p><b>Can not change "ImageLength" when using
separate planes</b>. Separate image planes are being used
(<i>PlanarConfiguration</i>=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
(<i>PlanarConfiguration</i>=1).</p>
<!-- INDENTATION -->
<p><b>%d: Sample out of range, max %d</b>. The <i>sample</i>
parameter was greater than the value of the SamplesPerPixel
tag.</p>
<!-- INDENTATION -->
<p><b>%s: No space for strip arrays .</b> There was not
enough space for the arrays that hold strip offsets and byte
counts.</p>
</td>
</table>
<a name="BUGS"></a>
<h2>BUGS</h2>
<!-- INDENTATION -->
<table width="100%" border=0 rules="none" frame="void"
cols="2" cellspacing="0" cellpadding="0">
<tr valign="top" align="left">
<td width="8%"></td>
<td width="91%">
<p>Writing subsampled YCbCR data does not work correctly
because, for <i>PlanarConfiguration</i>=2 the size of a
scanline is not calculated on a per-sample basis, and for
<i>PlanarConfiguration</i>=1 the library does not pack the
block-interleaved samples.</p>
</td>
</table>
<a name="SEE ALSO"></a>
<h2>SEE ALSO</h2>
<!-- INDENTATION -->
<table width="100%" border=0 rules="none" frame="void"
cols="2" cellspacing="0" cellpadding="0">
<tr valign="top" align="left">
<td width="8%"></td>
<td width="91%">
<p><b>TIFFOpen</b>(3TIFF),
<b>TIFFWriteEncodedStrip</b>(3TIFF),
<b>TIFFWriteRawStrip</b>(3TIFF), <b>libtiff</b>(3TIFF)</p>
<!-- INDENTATION -->
<p>Libtiff library home page:
<b>http://www.remotesensing.org/libtiff/</b></p>
</td>
</table>
<hr>
</body>
</html>