Hacker Guide

Introduction

VLC media player is a very popular, but quite large and complex piece of software.
It uses a large number of 3rd party libraries.

VLC development is open source, and then a large community of developers worldwide contribute to it.
However, entering a project such as VLC media player can be long and complex for new developers.

This guide seeks to help understanding the VLC code base and VLC internals to quickly get up to speed.
NB: this guide is not about compiling VLC.

A very good introduction to VLC can also be found on enjoythearchitecture.

The layers of VLC and libVLC

VLC's Core / libVLCcore

The most important (and probably most complex) part of VLC is the core, located in src/ in the repository.

• Introduction to the core
  • This is a MUST-READ for developers.
• VLC modules loading
  • How the numerous VLC modules work and are loaded.
• Input
  • How the main input chain works (slightly outdated)
• VLC Object Management
• VLC variables
• VLM Internals

Plugins / Modules

How to write a VLC module.

Input

• Access
  • An access module provides a byte stream from a location string MRL, like support for files, HTTP streams, webcams...
• Demuxer
  • A demux module parses a byte stream and splits it into elementary streams (tracks).
• Access-Demuxer
  • An access_demux module combines the functionality of access and demux (and bypass any stream filters), splitting elementary streams directly from a location string. It's used where the bytestream abstraction is inadequate.
• Stream Filters
  • A stream filter module converts a byte stream into another byte stream. It could be used for file or byte stream decryption, as it is already used for decompression (gzip, Bzip2, XZ) and multi-part files.
• Decoder
  • A decoder takes an elementary stream and convert into raw video, audio or text data, reading for output.

Audio

• Audio Filters
  • Audio Mixers
• Audio Output

Video

• Video Filters
  • Deinterlace
• Video Output

Interfaces

• Interfaces

Modules types not documented (yet)

Misc

• Visualization
• Packetizers

Streaming output

• Encoder
• Mux
• Stream Output
• Access Output

libVLC and bindings

• Using libvlc
• bindings

VLC source code overview

• VLC source tree
• Modules source tree
• VLC Preferences
• VLC Playlist and Media Library

Coding for VLC

• Patching
• Sending Patches
• Code Conventions
• Adding a module
• Documentation:Unicode
• Doxygen Documentation
• C Types
• Strings

Testing

• Test Suite

This page is part of official VLC media player Documentation (User Guide • Streaming HowTo • Hacker Guide • Modules)
Please read the Documentation Editing Guidelines before you edit the documentation

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.