Since I was looking for a class that will work with Qt or Win32 and provide mplayer support and I haven't found one I ported already known one from Gtk2 LCL. The code is available here:
http://project.ksplayer.com/browser/ksp/itools/player/cmplayer.pasTMPlayerControl is not a component (you don't install it on palette). You just put proper unit in uses section and create it as any other class. Before you start using it you should set a few properties. First is MPlayerPath which contains a path to mplayer. Second is WinID which is -wid switch passed to mplayer so player knows which control to paint with video.
Additionally in order to compile unit above (since it is taken from my application) you should do following things:
1. Remove Multilog from uses and remove all references to hLog object.
2. Remove kspfiles from uses and put following function in the code:
{$IFDEF WINDOWS}
function IsWin6: boolean;
var
osVerInfo: TOSVersionInfo;
begin
Result := false;
osVerInfo.dwOSVersionInfoSize := SizeOf(TOSVersionInfo) ;
if GetVersionEx(osVerInfo) then
begin
Result := osVerInfo.dwMajorVersion>=6;
end;
end;
{$ENDIF}
Of course this function will require Windows unit in uses (only Windows platform).
What is already done is playing video (tested with Qt interface and Windows Vista) and setting audio volume. What doesn't work is pausing/resuming video. Looping is not tested. Also events, getting movie length (and position) and seek function need to be still implemented.