Behavior recognition method and information processing apparatus

A non-transitory computer-readable recording medium having stored therein a program that causes a computer to execute a process, the process comprising:

• extracting skeleton information including a plurality of joint positions for each frame of an image;
• calculating a first set of motion feature amounts from the skeleton information;
• calculating a plot position by plotting the first set of motion feature amounts on a feature amount space defined by a second set of motion feature amounts, the plot position being a position where the first set of motion feature amounts is plotted on the feature amount space, the feature amount space having a plurality of mapping areas in which respective ranges corresponding to predetermined higher-level behaviors to be recognized are mapped;
• executing, when a degree of divergence from a minimum distance to other distances among distances between the plot position and each of the plurality of mapping areas satisfies a predetermined criterion, an update of expanding a mapping area at the minimum distance from the plot position based on the plot position;
• selecting the second sets of motion feature amounts from third sets of motion feature amounts extracted from respective combinations of basic motions corresponding to the predetermined higher-level behaviors;
• and
• mapping respective ranges in which the predetermined higher-level behaviors are observed, on the feature amount space defined by the second sets of motion feature amounts.

An information processing apparatus, comprising:

• a memory;
• and
• a processor coupled to the memory and the processor configured to:
• extract skeleton information including a plurality of joint positions for each frame of an image;
• calculate a first set of motion feature amounts from the skeleton information;
• calculate a plot position by plotting the first set of motion feature amounts on a feature amount space defined by a second set of motion feature amounts, the plot position being a position where the first set of motion feature amounts is plotted on the feature amount space, the feature amount space having a plurality of mapping areas in which respective ranges corresponding to predetermined higher-level behaviors to be recognized are mapped;
• execute, when a degree of divergence from a minimum distance to other distances among distances between the plot position and each of the plurality of mapping areas satisfies a predetermined criterion, an update of expanding a mapping area at the minimum distance from the plot position based on the plot position;
• select the second sets of motion feature amounts from third sets of motion feature amounts extracted from respective combinations of basic motions corresponding to the predetermined higher-level behaviors;
• and
• map respective ranges in which the predetermined higher-level behaviors are observed, on the feature amount space defined by the second sets of motion feature amounts.