Project: Sports Video Analysis
Sports video is structured, and its syntax is determined by rules of the game as well as rules of field production. And the domain knowledge is used in analysis.
Hereafter, our dicussion will be focused on soccer.Shooting scale and views
- 3 kinds of view according to the placement of camera and field shooting custom
i.e. global view, zoom-in view, and close-up
- These 3 classes are usually distinguished by their grass area ratio, as shown below
Global Zoom-in Close-upTemporal Syntactic Structure
- Soccer game is an alternative combination of plays and breaks.
- A play is a continuous time segment when the ball is inside the field and the game is going on.
- Break is the compliment set in time, i.e. when the ball is out of the field or the referee stops the play.
- Soccer game has a relatively loose time structure
- No canonical scene corresponding to certain events (unlike serve scene in tennis).
- No fixed semantic units during a play (unlike serve-hitA-hitB-... in tennis).
- Hightlights(such as shot, goal) are happening in a sporadic manner, hard to predict under a deterministic model.
- Production of soccer video observe common rules
- General idea: to convey global information, and closely follow the motion and highlights
- During a play: a majority of global view interleaved with short zoom-in and close-up
- During a break: a majority of zoom-in and close-upAnd these leads to our approach of mapping grass area to view, and view sequence to plays and breaks (see Current Results). Bob Burke, Frederick Shook, Chapter 12. Sports photography and reporting, in "Television field production and reporting", 2nd Ed, Longman Publisher USA, 1996