|
Server : Apache/2.4.62 System : FreeBSD fbsdweb2.web.rcn.net 14.1-RELEASE FreeBSD 14.1-RELEASE releng/14.1-n267679-10e31f0946d8 GENERIC amd64 User : www ( 80) PHP Version : 8.3.8 Disable Function : NONE Directory : /usr/local/share/doc/tiff-4.6.0/manual/ |
Upload File : |
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" /><meta name="generator" content="Docutils 0.19: https://docutils.sourceforge.io/" />
<title>Terminology — LibTIFF 4.6.0 documentation</title>
<link rel="stylesheet" type="text/css" href="_static/pygments.css" />
<link rel="stylesheet" type="text/css" href="_static/sphinxdoc.css" />
<script data-url_root="./" id="documentation_options" src="_static/documentation_options.js"></script>
<script src="_static/doctools.js"></script>
<script src="_static/sphinx_highlight.js"></script>
<link rel="index" title="Index" href="genindex.html" />
<link rel="search" title="Search" href="search.html" />
<link rel="next" title="Using The TIFF Library" href="libtiff.html" />
<link rel="prev" title="Building the TIFF Software Distribution" href="build.html" />
</head><body>
<div class="related" role="navigation" aria-label="related navigation">
<h3>Navigation</h3>
<ul>
<li class="right" style="margin-right: 10px">
<a href="genindex.html" title="General Index"
accesskey="I">index</a></li>
<li class="right" >
<a href="libtiff.html" title="Using The TIFF Library"
accesskey="N">next</a> |</li>
<li class="right" >
<a href="build.html" title="Building the TIFF Software Distribution"
accesskey="P">previous</a> |</li>
<li class="nav-item nav-item-0"><a href="index.html">LibTIFF 4.6.0 documentation</a> »</li>
<li class="nav-item nav-item-this"><a href="">Terminology</a></li>
</ul>
</div>
<div class="document">
<div class="documentwrapper">
<div class="bodywrapper">
<div class="body" role="main">
<section id="terminology">
<h1>Terminology<a class="headerlink" href="#terminology" title="Permalink to this heading">¶</a></h1>
<a class="reference internal image-reference" href="_images/strike.gif"><img alt="strike" src="_images/strike.gif" style="width: 128px;" /></a>
<p>The following definitions are used throughout this documentation.
They are consistent with the terminology used in the TIFF 6.0 specification.</p>
<dl class="simple">
<dt>Sample:</dt><dd><p>The unit of information stored in an image; often called a
channel elsewhere. Sample values are numbers, usually unsigned
integers, but possibly in some other format if the SampleFormat
tag is specified in a TIFF</p>
</dd>
<dt>Pixel:</dt><dd><p>A collection of one or more samples that go together.</p>
</dd>
<dt>Row:</dt><dd><p>An Nx1 rectangular collection of pixels.</p>
</dd>
<dt>Tile:</dt><dd><p>An NxM rectangular organization of data (or pixels).</p>
</dd>
<dt>Strip:</dt><dd><p>A tile whose width is the full image width.</p>
</dd>
<dt>Compression:</dt><dd><p>A scheme by which pixel or sample data are stored in
an encoded form, specifically with the intent of reducing the
storage cost.</p>
</dd>
<dt>Codec:</dt><dd><p>Software that implements the decoding and encoding algorithms
of a compression scheme.</p>
</dd>
</dl>
<dl class="simple" id="imagefiledirectory">
<dt>Image File Directory (IFD):</dt><dd><p>An Image File Directory - in short also <em>directory</em> -
contains information about the image,
as well as pointers (offsets) to the actual image data
within the on-disk file.
An IFD points either to the next IFD or shows with a ‘’0’’
that it is the last IFD in the IFD-chain.</p>
</dd>
<dt>Multi Images per TIFF file:</dt><dd><p>There may be more than one IFD in a TIFF file.
Each IFD defines a <em>subfile</em>.
One potential use of <em>subfiles</em> is to describe related images,
such as the pages of a facsimile transmission.
Such files are also named “<em>multi-page</em> TIFF” or “<em>multi-image</em> TIFF”.
Refer also to <a class="reference internal" href="multi_page.html"><span class="doc">Multi Page / Multi Image TIFF</span></a>.</p>
</dd>
</dl>
<dl class="simple" id="subfile">
<dt>Subfile:</dt><dd><p><em>Subfile</em> is a term in the TIFF 6.0 specification for
an image and its associated <em>Image File Directory (IFD)</em>
in a TIFF file containing one or more images.</p>
</dd>
</dl>
<p>In order to better understand how TIFF works (and consequently this
software) it is important to recognize the distinction between the
physical organization of image data as it is stored in a TIFF and how
the data is interpreted and manipulated as pixels in an image. TIFF
supports a wide variety of storage and data compression schemes that
can be used to optimize retrieval time and/or minimize storage space.
These on-disk formats are independent of the image characteristics; it
is the responsibility of the TIFF reader to process the on-disk storage
into an in-memory format suitable for an application. Furthermore, it
is the responsibility of the application to properly interpret the
visual characteristics of the image data. TIFF defines a framework for
specifying the on-disk storage format and image characteristics with
few restrictions. This permits significant complexity that can be
daunting. Good applications that handle TIFF work by handling as wide
a range of storage formats as possible, while constraining the
acceptable image characteristics to those that make sense for the
application.</p>
</section>
<div class="clearer"></div>
</div>
</div>
</div>
<div class="sphinxsidebar" role="navigation" aria-label="main navigation">
<div class="sphinxsidebarwrapper">
<div>
<h4>Previous topic</h4>
<p class="topless"><a href="build.html"
title="previous chapter">Building the TIFF Software Distribution</a></p>
</div>
<div>
<h4>Next topic</h4>
<p class="topless"><a href="libtiff.html"
title="next chapter">Using The TIFF Library</a></p>
</div>
<div role="note" aria-label="source link">
<h3>This Page</h3>
<ul class="this-page-menu">
<li><a href="_sources/terms.rst.txt"
rel="nofollow">Show Source</a></li>
</ul>
</div>
<div id="searchbox" style="display: none" role="search">
<h3 id="searchlabel">Quick search</h3>
<div class="searchformwrapper">
<form class="search" action="search.html" method="get">
<input type="text" name="q" aria-labelledby="searchlabel" autocomplete="off" autocorrect="off" autocapitalize="off" spellcheck="false"/>
<input type="submit" value="Go" />
</form>
</div>
</div>
<script>document.getElementById('searchbox').style.display = "block"</script>
</div>
</div>
<div class="clearer"></div>
</div>
<div class="related" role="navigation" aria-label="related navigation">
<h3>Navigation</h3>
<ul>
<li class="right" style="margin-right: 10px">
<a href="genindex.html" title="General Index"
>index</a></li>
<li class="right" >
<a href="libtiff.html" title="Using The TIFF Library"
>next</a> |</li>
<li class="right" >
<a href="build.html" title="Building the TIFF Software Distribution"
>previous</a> |</li>
<li class="nav-item nav-item-0"><a href="index.html">LibTIFF 4.6.0 documentation</a> »</li>
<li class="nav-item nav-item-this"><a href="">Terminology</a></li>
</ul>
</div>
<div class="footer" role="contentinfo">
© Copyright 1988-2022, LibTIFF contributors.
Created using <a href="https://www.sphinx-doc.org/">Sphinx</a> 7.0.1.
</div>
</body>
</html>