Seven Samurai is composed of three distinctive groups of people- the farmers, the bandits and the samurai. There are over a hundred farmers, forty bandits, and just seven samurai. Kurosawa keeps these three units apart in various ways.
The credit music is low drums and this becomes associated with the bandits, who appear in the opening sequence. The farmers’ music is folk- flute and percussion, while the samurai music is low humming male chorus. The three kinds of music are never together.
Other than distinction, the other beautiful compositional aspect of this film is motion. There is no shot in the film that has no motion, either in the object photographed, or in the movement of the camera itself. The motion may be small, like the quivering of nostrils of the village elder. The motion may even be majestic, like the sweeping frescos of the Samurai charges.
The other compositional feature of this film is attention to details of the visual surroundings. Kurosawa begins with a map- a bird eye view that immediately engages the audience. Using a map is a common feature of many other of his films like Stray Dog, The Hidden Fortress and High and Low. Other than a map, there is another technique Kurosawa regularly uses to keep the audience engaged. He allows the audience to keep track of score. The number of circles indicating the bandits in Seven Samurai, the number bullets in Stray Dog being some of the examples. And to top it all, Kurosawa gives a little bit of extra time in each shot to allow the audience to flow freely and subconsciously with the wonderful cinematic world Kurosawa creates.