Methods and apparatus to monitor environments
View Patent ↗Methods and apparatus to monitor environments are disclosed. An example method includes analyzing a plurality of three-dimensional data points having respective depth values representative of distances between a sensor and respective objects of an environment; when a first set of the three-dimensional data points has a first depth value less than a threshold, executing a first type of recognition analysis on a first area of the environment corresponding to the first set of the three-dimensional data points; and when a second set of the three-dimensional data points has a second depth value greater than the threshold, executing a second type of recognition analysis different than the first type of recognition analysis on a second area of the environment corresponding to the second set of the three-dimensional data points.
1. A tangible machine readable storage medium comprising instructions that, when executed, cause a machine to at least:
execute, in connection with a first frame of data, a three-dimensional recognition analysis on an object detected in an environment within a threshold distance from a sensor;
store a location of the object; and
in response to detecting that the first object has moved outside the threshold distance from the sensor in connection with a second frame subsequent to the first frame:
execute a two-dimensional recognition analysis on the object in the second frame; and
use the stored location of the object as a focal point for the two-dimensional analysis.
2. A storage medium as defined in claim 1 , wherein the instructions, when executed, cause the machine to use the stored location of the object as the focal point for the two-dimensional recognition analysis by limiting the two-dimensional recognition analysis to a portion of the second frame associated with the stored location of the object in the first frame.
3. A storage medium as defined in claim 1 , wherein the instructions, when executed, cause the machine to use the stored location of the object as the focal point for the two-dimensional recognition analysis by limiting the two-dimensional recognition analysis to a portion of the second frame corresponding to a shape and surrounding the stored location of the object in the frame.
4. A storage medium as defined in claim 1 , wherein the instructions, when executed, cause the machine to store the location of the object by recording a two-dimensional coordinate in association with the first frame.
5. A storage medium as defined in claim 1 , wherein the instructions, when executed, cause the machine to analyze captured three-dimensional data of the environment to determine whether the object is within the threshold distance from the sensor.
6. A storage medium as defined in claim 1 , wherein the instructions, when executed, cause the machine to execute the two-dimensional recognition analysis in response to occurrence of a time event.
7. A storage medium as defined in claim 1 , wherein the three-dimensional and the two-dimensional recognition analyses determine whether the respective objects of the environment correspond to people.
8. A storage medium as defined in claim 7 , wherein the instructions, when executed, cause the machine to calculate a people count using results of at least one of the three-dimensional or the two-dimensional recognition analyses.
9. An audience measurement device, comprising:
a first data analyzer to execute a first recognition analysis on three-dimensional data representative of a first object within a threshold distance from a three-dimensional sensor;
a second data analyzer to execute a second recognition analysis on two-dimensional data representative of a second object outside the threshold distance from the three-dimensional sensor; and
a counter to combine a first detection of a first person provided by the first data analyzer and a second detection of a second person provided by the second data analyzer to generate a people count for an environment, wherein at least one of the first data analyzer, the second data analyzer or the counter is implemented via a logic circuit.
10. An apparatus as defined in claim 9 , further comprising a crossover detector to detect the first person travelling from within the threshold distance to outside the threshold distance, the crossover detector to record a location of the first person when the first person travelled outside the threshold distance.
11. An apparatus as defined in claim 10 , further comprising a limiter to focus the second recognition analysis on the location of the first person.
12. An apparatus as defined in claim 11 , wherein the limiter is to define a boundary within the two-dimensional data in which to perform the second recognition analysis to areas adjacent to the location of the first person.
13. An apparatus as defined in claim 12 , wherein a shape of the boundary to be defined by the limiter depends on a type of body part detected by the first data analyzer.
14. A method comprising:
executing, via a processor, in connection with a first frame of data, a three-dimensional recognition analysis on an object detected in an environment within a threshold distance from a sensor;
storing a location of the object; and
in response to detecting that the first object has moved outside the threshold distance from the sensor in a second frame subsequent to the first frame:
executing, via the processor, a two-dimensional recognition analysis on the object in the second frame; and
using the stored location of the object as a focal point for the two-dimensional analysis.
15. A method as defined in claim 14 , wherein the using of the stored location of the object as the focal point for the two-dimensional recognition analysis comprises limiting the two-dimensional recognition analysis to a portion of the second frame associated with the stored location of the object in the first frame.
16. A method as defined in claim 14 , wherein the using of the stored location of the object as the focal point for the two-dimensional recognition analysis comprises limiting the two-dimensional recognition analysis to a portion of the second frame corresponding to a shape and surrounding the stored location of the object in the frame.
17. A method as defined in claim 14 , wherein the storing of the location of the object comprises recording a two-dimensional coordinate in association with the first frame.
18. A method as defined in claim 14 , further comprising analyzing captured three-dimensional data of the environment to determine whether the object is within the threshold distance from the sensor.
19. A method as defined in claim 14 , wherein the executing of the two-dimensional recognition analysis is in response to occurrence of a time event.
20. A method as defined in claim 14 , wherein the three-dimensional and the two-dimensional recognition analyses determine whether the respective objects environment correspond to people.
21. A method as defined in claim 20 , further comprising calculating a people count using results of at least one of the three-dimensional or the two-dimensional recognition analyses.