Information acquisition device, positional information storage method and storage medium

1. An information acquisition device, comprising:

a positioning unit that measures a current position and acquires positional information thereof;

an information acquisition unit that acquires information;

a storage unit that stores information acquired by the information acquisition unit and positional information acquired by the positioning unit; and

a control unit that (i) causes the positioning unit to sequentially perform positioning at a predetermined time interval, while the information acquisition unit is activated, (ii) causes a sequence of positional information which is acquired during the activation and in a predetermined time period to be stored in the storage unit without thinning, and (iii) causes positional information which is acquired during the activation and in another time period to be periodically thinned automatically such that only remaining positional information is stored in the storage unit;

wherein the predetermined time period is defined with a time at which acquisition of information was performed by the information acquisition unit as a reference point, and the another time period is outside the predetermined time period; and

wherein the control unit causes the positional information in the another time period to be stored in the storage unit, while the information acquisition unit is stopped, at a same time interval as an interval at which the positional information which has been thinned is to be stored in the storage unit.

2. The information acquisition device as set forth in claim 1 , further comprising a temporary storage unit that temporarily stores the positional information acquired by the information acquisition unit before the positional information is stored in the storage unit,

wherein the predetermined time period is a period including before and after the time at which the information was acquired, and the control unit causes the positional information to be thinned before the positional information is stored in the storage unit.

3. The information acquisition device as set forth in claim 1 , wherein the positioning unit is a GPS unit that measures a current position by receiving signals from GPS satellites.

4. The information acquisition device as set forth in claim 1 , wherein the positioning unit includes a GPS unit that measures a current position by receiving signals from GPS satellites and an autonomous navigation unit that measures a current position by autonomous navigation.

5. The information acquisition device as set forth in claim 4 , wherein the control unit causes positional information acquired by the GPS unit to be preferentially stored in the storage unit as positional information while the information acquisition unit is activated.

6. The information acquisition device as set forth in claim 4 , wherein the control unit causes the GPS unit to intermittently be activated while the information acquisition unit is stopped.

7. The information acquisition device as set forth in claim 1 , wherein the information acquisition unit is an imaging unit.

8. A positional information storage method of an imaging device that includes a positioning unit that measures a current position and acquires positional information thereof, an information acquisition unit that acquires information, and a storage unit that stores information acquired by the information acquisition unit and positional information acquired by the positioning unit, the method comprising:

causing the positioning unit to sequentially perform positioning at a predetermined time interval, while the information acquisition unit is activated;

causing a sequence of positional information which is acquired during the activation and in a predetermined time period to be stored in the storage unit without thinning; and

causing positional information which is acquired during the activation and in another time period to be periodically thinned automatically such that only remaining positional information is stored in the storage unit;

wherein the predetermined time period is defined with a time at which acquisition of information was performed by the information acquisition unit as a reference point, and the another time period is outside the predetermined time period;

wherein positional information is caused to be stored in the storage unit in the another time period, while the information acquisition unit is stopped, at a same time interval as an interval at which the positional information which has been thinned is to be stored in the storage unit.

9. A non-transitory computer readable storage medium having a program stored thereon which is executable by a computer of an information acquisition device that includes a positioning unit that measures a current position and acquires positional information thereof, an information acquisition unit that acquires information, and a storage unit that stores information acquired by the information acquisition unit and positional information acquired by the positioning unit, the program controlling the computer to function as:

a control unit that (i) causes the positioning unit to sequentially perform positioning at a predetermined time interval, while the information acquisition unit is activated, (ii) causes a sequence of positional information which is acquired during the activation and in a predetermined time period to be stored in the storage unit without thinning, and (iii) causes positional information which is acquired during the activation and in another time period to be periodically thinned automatically such that only remaining positional information is stored in the storage unit;

wherein the predetermined time period is defined with a time at which acquisition of information was performed by the information acquisition unit as a reference point, and the another time period is outside the predetermined time period;

wherein the control unit causes the positional information in the another time period to be stored in the storage unit, while the information acquisition unit is stopped, at a same time interval as an interval at which the positional information which has been thinned is to be stored in the storage unit.