Basically we would like to develop a software (web or desktop) that allows for easy collection of all data in a soccer match based on video of said game. A good reference for this is OPTA, if you have developed something like this in the past that would be great to know as well as potential budgets that would be required. An interface for example that allows a user to input quickly via keyboard and mouse every time the balls gets passed, kicked, etc... and on what part of the pitch the event happened is basically the idea. It would need to use live video and ideally a superposition of live video on top of the pitch to draw trajectories, which would be the tricky part. Alternatively the video could be placed on top of the pitch graph.
Alternatively a methodology like this would be potentially suitable. Bear in mind timestamps for the events would have to be linked to the video/game's time.
Also this is what it would look like if video was superimposed onto pitch on screen, this would be an important option also: