1<!-- Creator : groff version 1.18.1 --> 2<!-- CreationDate: Sat Feb 24 18:37:20 2007 --> 3<html> 4<head> 5<meta name="generator" content="groff -Thtml, see www.gnu.org"> 6<meta name="Content-Style" content="text/css"> 7<title>TIFFMEDIAN</title> 8</head> 9<body> 10 11<h1 align=center>TIFFMEDIAN</h1> 12<a href="#NAME">NAME</a><br> 13<a href="#SYNOPSIS">SYNOPSIS</a><br> 14<a href="#DESCRIPTION">DESCRIPTION</a><br> 15<a href="#OPTIONS">OPTIONS</a><br> 16<a href="#NOTES">NOTES</a><br> 17<a href="#SEE ALSO">SEE ALSO</a><br> 18 19<hr> 20<a name="NAME"></a> 21<h2>NAME</h2> 22<!-- INDENTATION --> 23<table width="100%" border=0 rules="none" frame="void" 24 cols="2" cellspacing="0" cellpadding="0"> 25<tr valign="top" align="left"> 26<td width="8%"></td> 27<td width="91%"> 28<p>tiffmedian − apply the median cut algorithm to data 29in a <small>TIFF</small> file</p> 30</td> 31</table> 32<a name="SYNOPSIS"></a> 33<h2>SYNOPSIS</h2> 34<!-- INDENTATION --> 35<table width="100%" border=0 rules="none" frame="void" 36 cols="2" cellspacing="0" cellpadding="0"> 37<tr valign="top" align="left"> 38<td width="8%"></td> 39<td width="91%"> 40<p><b>tiffmedian</b> [ <i>options</i> ] <i>input.tif 41output.tif</i></p> 42</td> 43</table> 44<a name="DESCRIPTION"></a> 45<h2>DESCRIPTION</h2> 46<!-- INDENTATION --> 47<table width="100%" border=0 rules="none" frame="void" 48 cols="2" cellspacing="0" cellpadding="0"> 49<tr valign="top" align="left"> 50<td width="8%"></td> 51<td width="91%"> 52<p><i>tiffmedian</i> applies the median cut algorithm to an 53<small>RGB</small> image in <i>input.tif</i> to generate a 54palette image that is written to <i>output.tif</i>. The 55generated colormap has, by default, 256 entries. The image 56data is quantized by mapping each pixel to the closest color 57values in the colormap.</p> 58</td> 59</table> 60<a name="OPTIONS"></a> 61<h2>OPTIONS</h2> 62<!-- TABS --> 63<table width="100%" border=0 rules="none" frame="void" 64 cols="5" cellspacing="0" cellpadding="0"> 65<tr valign="top" align="left"> 66<td width="11%"></td> 67<td width="2%"> 68 69<p><b>−c</b></p> 70</td> 71<td width="5%"></td> 72<td width="80%"> 73 74<p>Specify the compression to use for data written to the 75output file: <b>none</b> for no compression, <b>packbits</b> 76for PackBits compression, <b>lzw</b> for Lempel-Ziv & 77Welch compression, and <b>zip</b> for Deflate compression. 78By default <i>tiffmedian</i> will compress data according to 79the value of the <i>Compression</i> tag found in the source 80file.</p> 81</td> 82<td width="0%"> 83</td> 84</table> 85<!-- INDENTATION --> 86<table width="100%" border=0 rules="none" frame="void" 87 cols="2" cellspacing="0" cellpadding="0"> 88<tr valign="top" align="left"> 89<td width="17%"></td> 90<td width="82%"> 91<p><small>LZW</small> compression can be specified together 92with a <i>predictor</i> value. A predictor value of 2 causes 93each scanline of the output image to undergo horizontal 94differencing before it is encoded; a value of 1 forces each 95scanline to be encoded without differencing. LZW-specific 96options are specified by appending a 97‘‘:’’-separated list to the 98‘‘lzw’’ option; e.g. <b>−c 99lzw:2</b> for <small>LZW</small> compression with horizontal 100differencing.</p> 101</td> 102</table> 103<!-- TABS --> 104<table width="100%" border=0 rules="none" frame="void" 105 cols="5" cellspacing="0" cellpadding="0"> 106<tr valign="top" align="left"> 107<td width="10%"></td> 108<td width="2%"> 109 110<p><b>−C</b></p> 111</td> 112<td width="6%"></td> 113<td width="80%"> 114 115<p>Specify the number of entries to use in the generated 116colormap. By default all 256 entries/colors are used.</p> 117</td> 118<td width="0%"> 119</td> 120<tr valign="top" align="left"> 121<td width="10%"></td> 122<td width="2%"> 123 124<p><b>−f</b></p> 125</td> 126<td width="6%"></td> 127<td width="80%"> 128 129<p>Apply Floyd-Steinberg dithering before selecting a 130colormap entry.</p> 131</td> 132<td width="0%"> 133</td> 134<tr valign="top" align="left"> 135<td width="10%"></td> 136<td width="2%"> 137 138<p><b>−r</b></p> 139</td> 140<td width="6%"></td> 141<td width="80%"> 142 143<p>Specify the number of rows (scanlines) in each strip of 144data written to the output file. By default, 145<i>tiffmedian</i> attempts to set the rows/strip that no 146more than 8 kilobytes of data appear in a strip.</p> 147</td> 148<td width="0%"> 149</td> 150</table> 151<a name="NOTES"></a> 152<h2>NOTES</h2> 153<!-- INDENTATION --> 154<table width="100%" border=0 rules="none" frame="void" 155 cols="2" cellspacing="0" cellpadding="0"> 156<tr valign="top" align="left"> 157<td width="8%"></td> 158<td width="91%"> 159<p>This program is derived from Paul Heckbert’s 160<i>median</i> program.</p> 161</td> 162</table> 163<a name="SEE ALSO"></a> 164<h2>SEE ALSO</h2> 165<!-- INDENTATION --> 166<table width="100%" border=0 rules="none" frame="void" 167 cols="2" cellspacing="0" cellpadding="0"> 168<tr valign="top" align="left"> 169<td width="8%"></td> 170<td width="91%"> 171<p><b>pal2rgb</b>(1), <b>tiffinfo</b>(1), <b>tiffcp</b>(1), 172<b>tiffcmp</b>(1), <b>libtiff</b>(3TIFF)</p> 173<!-- INDENTATION --> 174<p><b>Color Image Quantization for Frame Buffer Display</b>, 175Paul Heckbert, SIGGRAPH proceedings, 1982, pp. 297-307.</p> 176<!-- INDENTATION --> 177<p>Libtiff library home page: 178<b>http://www.simplesystems.org/libtiff/</b></p> 179</td> 180</table> 181<hr> 182</body> 183</html> 184