158 lines
5.1 KiB
HTML
158 lines
5.1 KiB
HTML
<!-- Creator : groff version 1.18.1 -->
|
|
<!-- CreationDate: Sat Feb 24 18:37:17 2007 -->
|
|
<html>
|
|
<head>
|
|
<meta name="generator" content="groff -Thtml, see www.gnu.org">
|
|
<meta name="Content-Style" content="text/css">
|
|
<title>TIFFReadScanline</title>
|
|
</head>
|
|
<body>
|
|
|
|
<h1 align=center>TIFFReadScanline</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>TIFFReadScanline − read and decode a scanline of
|
|
data from 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 TIFFReadScanline(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>Read the data for the specified row into the (user
|
|
supplied) data buffer <i>buf</i>. The data are returned
|
|
decompressed and, in the native byte- and bit-ordering, but
|
|
are otherwise packed (see further below). The buffer must be
|
|
large enough to hold an entire scanline of data.
|
|
Applications should call the routine <i>TIFFScanlineSize</i>
|
|
to find out the size (in bytes) of a scanline buffer. The
|
|
<i>row</i> parameter is always used by
|
|
<i>TIFFReadScanline</i>; the <i>sample</i> parameter is used
|
|
only if data are organized in separate planes
|
|
(<i>PlanarConfiguration</i>=2).</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 attempts to hide bit- and byte-ordering
|
|
differences between the image and the native machine by
|
|
converting data to the native machine order. Bit reversal is
|
|
done if the <i>FillOrder</i> tag is opposite to the native
|
|
machine bit order. 16- and 32-bit samples are automatically
|
|
byte-swapped if the file was written with a byte order
|
|
opposite to the native machine byte order,</p>
|
|
<!-- INDENTATION -->
|
|
<p>In C++ the <i>sample</i> parameter defaults to 0.</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>TIFFReadScanline</i> returns −1 if it detects an
|
|
error; otherwise 1 is returned.</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>Compression algorithm does not support random
|
|
access</b>. Data was requested in a non-sequential order
|
|
from a file that uses a compression algorithm and that has
|
|
<i>RowsPerStrip</i> greater than one. That is, data in the
|
|
image is 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
|
|
accessed sequentially, or the file should be converted so
|
|
that each strip is made up of one row of data.</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>Reading 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 unpack the
|
|
block-interleaved samples; use the strip- and tile-based
|
|
interfaces to read these formats.</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>TIFFReadEncodedStrip</b>(3TIFF),
|
|
<b>TIFFReadRawStrip</b>(3TIFF), <b>libtiff</b>(3TIFF)</p>
|
|
<!-- INDENTATION -->
|
|
<p>Libtiff library home page:
|
|
<b>http://www.simplesystems.org/libtiff/</b></p>
|
|
</td>
|
|
</table>
|
|
<hr>
|
|
</body>
|
|
</html>
|