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## Introduction

&GStreamer; is an exremely powerful and versatile framework for creating streaming media applications. Many of the virtues of the &GStreamer; framework come from its modularity: &GStreamer; can seamlessly incorporate new plugin modules. But because modularity and power often come at a cost of greater complexity (consider, for example, CORBA), writing new plugins is not always easy.

This guide is intended to help you understand the &GStreamer; framework (version &GST_VERSION;) so you can develop new plugins to extend the existing functionality. The guide addresses most issues by following the development of an example plugin - an audio filter plugin - written in C. However, the later parts of the guide also present some issues involved in writing other types of plugins, and the end of the guide describes some of the Python bindings for &GStreamer;.

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## Building a Filter

You are now ready to learn how to build a plugin. In this part of the guide, you will learn how to apply basic &GStreamer; and GNOME programming concepts to write a simple plugin. The previous parts of the guide have contained no explicit example code, perhaps making things a bit abstract and difficult to understand. In contrast, this section will present both applications and code by following the development of an example audio filter plugin called ExampleFilter.

The example filter will begin with a single input pad and a single output pad. The filter will, at first, simply pass media and event data from its sink pad to its source pad without modification. But by the end of this part of the guide, you will learn to add some more interesting functionality, including properties and signal handlers. And after reading the next part of the guide, , you will be able to add even more functionality to your plugins.

The example code used in this part of the guide can be found in `examples/pwg/examplefilter/` in your &GStreamer; directory.

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## Advanced Filter Concepts

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## Other Element Types

&OTHER_SOURCE; &OTHER_SINK; &OTHER_AUTOPLUGGER;

## Appendices

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