Old Python bindings

Python binding documentation

For a while, there has been a basic python binding for libvlc, that was used for streaming. A more complete (with a hopefully generic API that can be reused by other players) has been developped, based on the MediaControlAPI.

Sources are browsable from python binding and a code sample can be found in [1].

Basics

The vlc python module provides 2 main classes : MediaControl and Object.

vlc.Object provides a binding to the vlc object architecture. It allows to manipulate variables and configuration options, and explore the object hierrarchy. The vlcdebug.py script, located in the python bindings directory, wraps around the vlc.Object to provide an easier access to variables and objects (as illustrated in the code sample in [2]).

vlc.MediaControl implements the MediaControlAPI.

Tips and tricks

Snapshot support

In order to get snapshot support, you have to activate the snapshot vout module through a clone video filter. The following code gives a way to achieve this :

 mc=vlc.MediaControl([ "--vout-filter", "clone" ])
 o=VLC.Object(0)
 o.config_set("clone-vout-list", "default,snapshot")
 o.config_set("snapshot-width", 320)
 o.config_set("snapshot-height", 200)

Note that all config options could have been given on the command line, but this illustrates the use of the vlc.Object API.

Win32 initialization

If the vlc module was not compiled with the exact same prefix as the VLC installation (e.g. c:\\Program Files\\Videolan), then it cannot find itself the installation directory (stored in the registry Software\VideoLAN\VLC\Path), and the MediaControl instanciation will fail with a message like "Cannot find interface plugins".

The workaround consists in changing directory to the VLC installation directory before instanciating the MediaControl object.

   def get_registry_value (self, subkey, name):
       import _winreg
       value = None
       for hkey in _winreg.HKEY_LOCAL_MACHINE, _winreg.HKEY_CURRENT_USER:
           try:
               reg = _winreg.OpenKey(hkey, subkey)
               value, type_id = _winreg.QueryValueEx(reg, name)
               _winreg.CloseKey(reg)
           except _winreg.error:
               pass
       return value
   
   vlcpath=get_registry_value('Software\\VideoLAN\\VLC','InstallDir')
   if vlcpath is None:
       print "Cannot locate VLC installation directory"
   else:
       os.chdir(vlcpath)
       mc=vlc.MediaControl()