pwg: improve allocation docs

This commit is contained in:
Wim Taymans 2013-04-27 20:33:06 +02:00
parent b48400b7a4
commit 25fc832d49

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@ -41,12 +41,22 @@
never be changed after the object is created, however, the offset never be changed after the object is created, however, the offset
and size can be changed. and size can be changed.
</para> </para>
<sect2 id="section-allocation-allocator" xreflabel="GstAllocator">
<title>GstAllocator</title>
<para> <para>
<classname>GstMemory</classname> objects are created by a <classname>GstMemory</classname> objects are created by a
<classname>GstAllocator</classname> object. To implement support <classname>GstAllocator</classname> object. Most allocators implement the
for a new kind of memory type, you must implement a new allocator default <function>gst_allocator_alloc()</function> method but some allocator
object. might implement a different method, for example when additional parameters
are needed to allocate the specific memory.
</para> </para>
<para>
Different allocators exist for, for example, system memory, shared memory
and memory backed by a DMAbuf file descriptor. To implement support for a
new kind of memory type, you must implement a new allocator object as shown
below.
</para>
</sect2>
<sect2 id="section-allocation-memory-ex" xreflabel="GstMemory-ex"> <sect2 id="section-allocation-memory-ex" xreflabel="GstMemory-ex">
<title>GstMemory API example</title> <title>GstMemory API example</title>
<para> <para>
@ -88,7 +98,7 @@
</programlisting> </programlisting>
</sect2> </sect2>
<sect2 id="section-allocation-allocator" xreflabel="GstAllocator"> <sect2 id="section-allocation-allocator-ex" xreflabel="GstAllocator-ex">
<title>Implementing a GstAllocator</title> <title>Implementing a GstAllocator</title>
<para> <para>
WRITEME WRITEME
@ -209,14 +219,9 @@
<title>GstMeta</title> <title>GstMeta</title>
<para> <para>
With the <classname>GstMeta</classname> system you can add arbitrary With the <classname>GstMeta</classname> system you can add arbitrary
structures of on buffers. These structures describe extra properties structures on buffers. These structures describe extra properties
of the buffer such as cropping, stride, region of interest etc. of the buffer such as cropping, stride, region of interest etc.
</para> </para>
<para>
Metadata is also used to store, for example, the X image that is
backing up the memory of the buffer. This makes it easier for elements
to locate the X image from the buffer.
</para>
<para> <para>
The metadata system separates API specification (what the metadata The metadata system separates API specification (what the metadata
and its API look like) and the implementation (how it works). This makes and its API look like) and the implementation (how it works). This makes