I want to integrate Audio and Video support in my application using the Phonon framework. I'm handling protected data (mp3, avi etc.). Therefore I'm writing those files encrypted to the filesystem.

To avoid loading a whole video in the buffer I subclassed QIODevice and provided a custom IODevice which decrypts the encrypted content 'on-the-fly' when Phonon asks for more bytes. (function readData)

Encryption/Decryption works fine, no problems. Now I tried to play different video types (Audio: mp3 is working) with my Phonon-Player.
AVI: working
WMV: not working

Now under "doc.qt.digia.com/main-snapshot/phonon-mediasource.html#MediaSource-6" I noticed the following sentence:

"Warning: On Windows, we only support QIODevices containing the avi, mp3, or mpg formats. Use the constructor that takes a file name to open files (the Qt backend does not use a QFile internally)."

Is there any way to avoid this restrictions and to extend this functionality? Unfortunalety I definitely have to use encrypted files.