Mirrored from http://ftp.lug.udel.edu/MPlayer/releases/codecs/qt-howto.txt

How to get WIN32 QuickTime audio/video codecs working with MPlayer?

1. Get MPlayer CVS (read the docs how to...), and compile this way:
./configure --enable-qtx-codecs --enable-win32
make

2. Get the QuickTime DLLs pack:
QT6 DLLs (should be faster): http://www.mplayerhq.hu/~alex/codecs/qt6dlls.tar.bz2 QT5 DLLs (we (developers) use this): http://www.mplayerhq.hu/~alex/codecs/qt5dlls.tar.bz2 Or if you have already downloaded the qt-dotwine.tar.bz2,
you can use it too. NOTE: qt6-dlls.tar.bz2 from releases/ doesn't contains qtmlClient.dll!

3. Extract the files:
Normally the WIN32 codecs directory is the following: /usr/lib/win32 Extract the QuickTime.qts, QuickTimeEssentials.qtx and qtmlClient.dll to that dir (or to that what you have configured). (In case of qt-dotwine.tar.bz2, the dlls can be found in .wine/fake_windows/Windows/System/ directory)

3a. Extract the extras:
If you want to be really up-to-date, you can also copy the not-yet supported codecs too: 3ivx Delta 3.5.qtx, On2_VP3.qtx, ZyGoVideo.qtx, BeHereiVideo.qtx. They can be found in the http://www.mplayerhq.hu/~alex/codecs/qtextras.tar.bz2 archive.

4. It should work now. Else send real bug reports to the mplayer-users@mplayerhq.hu list! (and only to that one!) And please include that which codec pack you have chosen.