1<!-- Creator : groff version 1.18.1 --> 2<!-- CreationDate: Sat Feb 24 18:37:16 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>TIFFReadDirectory</title> 8</head> 9<body> 10 11<h1 align=center>TIFFReadDirectory</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="#NOTES">NOTES</a><br> 16<a href="#RETURN VALUES">RETURN VALUES</a><br> 17<a href="#DIAGNOSTICS">DIAGNOSTICS</a><br> 18<a href="#SEE ALSO">SEE ALSO</a><br> 19 20<hr> 21<a name="NAME"></a> 22<h2>NAME</h2> 23<!-- INDENTATION --> 24<table width="100%" border=0 rules="none" frame="void" 25 cols="2" cellspacing="0" cellpadding="0"> 26<tr valign="top" align="left"> 27<td width="8%"></td> 28<td width="91%"> 29<p><big>TIFFReadDirectory − get the contents of the 30next directory in an open</big> TIFF <big>file</big></p> 31</td> 32</table> 33<a name="SYNOPSIS"></a> 34<h2>SYNOPSIS</h2> 35<!-- INDENTATION --> 36<table width="100%" border=0 rules="none" frame="void" 37 cols="2" cellspacing="0" cellpadding="0"> 38<tr valign="top" align="left"> 39<td width="8%"></td> 40<td width="91%"> 41<p><big><b>#include <tiffio.h></b></big></p> 42<!-- INDENTATION --> 43<p><big><b>int TIFFReadDirectory(TIFF 44*</b><i>tif</i><b>)</b></big></p> 45</td> 46</table> 47<a name="DESCRIPTION"></a> 48<h2>DESCRIPTION</h2> 49<!-- INDENTATION --> 50<table width="100%" border=0 rules="none" frame="void" 51 cols="2" cellspacing="0" cellpadding="0"> 52<tr valign="top" align="left"> 53<td width="8%"></td> 54<td width="91%"> 55<p><big>Read the next directory in the specified file and 56make it the current directory. Applications only need to 57call <i>TIFFReadDirectory</i> to read multiple subfiles in a 58single</big> TIFF <big>file— the first directory in a 59file is automatically read when <i>TIFFOpen</i> is 60called.</big></p> 61</td> 62</table> 63<a name="NOTES"></a> 64<h2>NOTES</h2> 65<!-- INDENTATION --> 66<table width="100%" border=0 rules="none" frame="void" 67 cols="2" cellspacing="0" cellpadding="0"> 68<tr valign="top" align="left"> 69<td width="8%"></td> 70<td width="91%"> 71<p><big>If the library is compiled with</big> 72STRIPCHOP_SUPPORT <big>enabled, then images that have a 73single uncompressed strip or tile of data are automatically 74treated as if they were made up of multiple strips or tiles 75of approximately 8 kilobytes each. This operation is done 76only in-memory; it does not alter the contents of the file. 77However, the construction of the ‘‘chopped 78strips’’ is visible to the application through 79the number of strips [tiles] returned by 80<i>TIFFNumberOfStrips</i> 81[<i>TIFFNumberOfTiles</i>].</big></p> 82</td> 83</table> 84<a name="RETURN VALUES"></a> 85<h2>RETURN VALUES</h2> 86<!-- INDENTATION --> 87<table width="100%" border=0 rules="none" frame="void" 88 cols="2" cellspacing="0" cellpadding="0"> 89<tr valign="top" align="left"> 90<td width="8%"></td> 91<td width="91%"> 92<p><big>If the next directory was successfully read, 1 is 93returned. Otherwise, 0 is returned if an error was 94encountered, or if there are no more directories to be 95read.</big></p> 96</td> 97</table> 98<a name="DIAGNOSTICS"></a> 99<h2>DIAGNOSTICS</h2> 100<!-- INDENTATION --> 101<table width="100%" border=0 rules="none" frame="void" 102 cols="2" cellspacing="0" cellpadding="0"> 103<tr valign="top" align="left"> 104<td width="8%"></td> 105<td width="91%"> 106<p><big>All error messages are directed to the 107<i>TIFFError</i>(3TIFF) routine. All warning messages are 108directed to the <i>TIFFWarning</i>(3TIFF) routine.</big></p> 109<!-- INDENTATION --> 110<p><big><b>Seek error accessing TIFF directory</b>. An error 111occurred while positioning to the location of the 112directory.</big></p> 113<!-- INDENTATION --> 114<p><big><b>Wrong data type %d for field "%s"</b>. 115The tag entry in the directory had an incorrect data type. 116For example, an <i>ImageDescription</i> tag with a</big> 117SHORT <big>data type.</big></p> 118<!-- INDENTATION --> 119<p><big><b>TIFF directory is missing required "%s" 120field</b>. The specified tag is required to be present by 121the</big> TIFF <big>5.0 specification, but is missing. The 122directory is (usually) unusable.</big></p> 123<!-- INDENTATION --> 124<p><big><b>%s: Rational with zero denominator</b>. A 125directory tag has a</big> RATIONAL <big>value whose 126denominator is zero.</big></p> 127<!-- INDENTATION --> 128<p><big><b>Incorrect count %d for field "%s" (%lu, 129expecting %lu); tag ignored</b>. The specified tag’s 130count field is bad. For example, a count other than 1 for a 131<i>SubFileType</i> tag.</big></p> 132<!-- INDENTATION --> 133<p><big><b>Cannot handle different per-sample values for 134field "%s"</b>. The tag has <i>SamplesPerPixel</i> 135values and they are not all the same; e.g. 136<i>BitsPerSample</i>. The library is unable to handle images 137of this sort.</big></p> 138<!-- INDENTATION --> 139<p><big><b>Count mismatch for field "%s"; 140expecting %d, got %d</b>. The count field in a tag does not 141agree with the number expected by the library. This should 142never happen, so if it does, the library refuses to read the 143directory.</big></p> 144<!-- INDENTATION --> 145<p><big><b>Invalid TIFF directory; tags are not sorted in 146ascending order</b>. The directory tags are not properly 147sorted as specified in the</big> TIFF <big>5.0 148specification. This error is not fatal.</big></p> 149<!-- INDENTATION --> 150<p><big><b>Ignoring unknown field with tag %d (0x%x)</b>. An 151unknown tag was encountered in the directory; the library 152ignores all such tags.</big></p> 153<!-- INDENTATION --> 154<p><big><b>TIFF directory is missing requred 155"ImageLength" field</b>. The image violates the 156specification by not having a necessary field. There is no 157way for the library to recover from this error.</big></p> 158<!-- INDENTATION --> 159<p><big><b>TIFF directory is missing requred 160"PlanarConfig" field</b>. The image violates the 161specification by not having a necessary field. There is no 162way for the library to recover from this error.</big></p> 163<!-- INDENTATION --> 164<p><big><b>TIFF directory is missing requred 165"StripOffsets" field</b>. The image has multiple 166strips, but is missing the tag that specifies the file 167offset to each strip of data. There is no way for the 168library to recover from this error.</big></p> 169<!-- INDENTATION --> 170<p><big><b>TIFF directory is missing requred 171"TileOffsets" field</b>. The image has multiple 172tiles, but is missing the tag that specifies the file offset 173to each tile of data. There is no way for the library to 174recover from this error.</big></p> 175<!-- INDENTATION --> 176<p><big><b>TIFF directory is missing required 177"StripByteCounts" field</b>. The image has 178multiple strips, but is missing the tag that specifies the 179size of each strip of data. There is no way for the library 180to recover from this error.</big></p> 181<!-- INDENTATION --> 182<p><big><b>TIFF directory is missing required 183"StripByteCounts" field, calculating from 184imagelength</b>. The image violates the specification by not 185having a necessary field. However, when the image is 186comprised of only one strip or tile, the library will 187estimate the missing value based on the file size.</big></p> 188<!-- INDENTATION --> 189<p><big><b>Bogus "StripByteCounts" field, ignoring 190and calculating from imagelength</b>. Certain vendors 191violate the specification by writing zero for the 192StripByteCounts tag when they want to leave the value 193unspecified. If the image has a single strip, the library 194will estimate the missing value based on the file 195size.</big></p> 196</td> 197</table> 198<a name="SEE ALSO"></a> 199<h2>SEE ALSO</h2> 200<!-- INDENTATION --> 201<table width="100%" border=0 rules="none" frame="void" 202 cols="2" cellspacing="0" cellpadding="0"> 203<tr valign="top" align="left"> 204<td width="8%"></td> 205<td width="91%"> 206<p><big><b>TIFFOpen</b>(3TIFF), 207<b>TIFFWriteDirectory</b>(3TIFF), 208<b>TIFFSetDirectory</b>(3TIFF), 209<b>TIFFSetSubDirectory</b>(3TIFF), 210<b>libtiff</b>(3TIFF)</big></p> 211<!-- INDENTATION --> 212<p><big>Libtiff library home page: 213<b>http://www.simplesystems.org/libtiff/</b></big></p> 214</td> 215</table> 216<hr> 217</body> 218</html> 219