I need a video player in my PySide application on Windows without any dependencies. Right now I play a video in a QWebView that loads Flash, which works okay, except most of the people using the application are running it on freshly installed copies of Windows which lack Flash, and they aren't willing to install Flash just to play the video in my application.
I could include the flash plugin with my distribution, but that's disallowed by Adobe's licensing.
I must have tried at least two dozen things, but nothing has worked well enough so far. The things that have worked best so far are:

Flash, licensing forbids it from being packed in with my app
PyGame, 1 - only accepted mpeg-1 files, which I've found are massive, 2 - has a tendency to crash
QMovie - seems to only support .mng files, which I've been unable to find a converter for. Additionally, that format is visual only - I need audio, too.

I've been trying to get PyMedia to work, but it's refusing to install (it wants Python 2.7 but I have Python 2.7.3. I've tried installing multiple copies of Python and downgrading before... it's just not worth the headache of trying to get all my code to run with a single version.)
Qt's Phonon module plays Videos using the codecs installed  in the operating system. So depending on the lowest Version of Windows you plan to support, you could chose one of the preinstalled codecs. Like wmv7 for XP.
Alternatively you could use Phonon and install an efficient free codec like x264.
Play videos with Python on Windows without Dependencies?