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HDF5/H5Z API Specification
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<h1>H5Z: Compression Interface</h1>
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<h2>Compression API Functions</h2>
This function enable the user to configure a new compression
method for the local environment.
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<li><a href="#Compression-Register">H5Zregister</a>
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<p>
HDF5 supports compression of raw data by compression methods
built into the library or defined by an application.
A compression method is associated with a dataset when the dataset is
created and is applied independently to each storage chunk of the dataset.
The dataset must use the <code>H5D_CHUNKED</code> storage layout.
<p>
The HDF5 library does not support compression for contiguous datasets
because of the difficulty of implementing random access for partial I/O.
Compact dataset compression is not supported because it would not produce
significant results.
<p>
See <a href="Datasets.html"><cite>The Dataset Interface (H5D)</cite></a>
in the <cite>HDF5 User's Guide</cite> for further information regarding
data compression.
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Compression-Register">H5Zregister</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Zregister</code>(<em>H5Z_method_t</em> <code>method</code>,
<em>const char *</em><code>name</code>,
<em>H5Z_func_t</em> <code>function</code>
)
<dt><strong>Purpose:</strong>
<dd> Registers new compression / uncompression function.
<dt><strong>Description:</strong>
<dd><code>H5Zregister</code> registers a new compression / uncompression
function for the compression method specified by
the method number, <code>method</code>.
<p>
<code>name</code> is used for debugging and may be the null pointer.
<p>
<code>function</code> is a user-defined function providing both
compression and uncompression; it may be the null pointer.
<p>
The statistics associated with a method number are not reset
by this function; they accumulate over the life of the library.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>H5Z_method_t</em> <code>method</code>
<dd>IN: Number specifying compression method.
<dt><em>const char *</em><code>name</code>
<dd>IN: Name associated with the method number.
Used for debugging purposes only.
<dt><em>H5Z_func_t</em> <code>function</code>
<dd>IN: Compression / uncompression method.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns a non-negative value if successful;
otherwise returns a negative value.
</dl>
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Last modified: 6 February 2002
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Describes HDF5 Release 1.4.4, July 2002
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