Aquatic organism observation device, aquatic organism observation system, aquatic organism observation method, and recording medium
To observe sounds produced by aquatic organisms with less effort, this aquatic organism observation device is made to include an aquatic organism information detection unit for detecting, from sound data that has been acquired using an optical fiber installed in or at the bottom of water and is related to sound at various positions on the optical fiber, a sound emitted by an aquatic organism at a sound data acquisition time and location, and an output unit for outputting aquatic organism information.
1. An aquatic organism observation device comprising:
an aquatic organism information detector comprising a processor configured to execute a program, and a storage storing information about a manufacturing or construction of an optical fiber provided in an optical cable,
wherein, by executing the program, the aquatic organism information detector is configured to:
detect, from sound data being acquired by the optical fiber that is installed in water or at a bottom of water and being data relating to a sound at each position of the optical fiber, a sound emitted by an aquatic organism at a time and a position at which the sound data have been acquired,
identify a sound emitted from a same sound source, among sounds detected at a plurality of positions of the optical fiber, and
perform processing of correcting, based on information about an installation state of the optical cable stored in the storage, the sound data to reduce an influence of a sensitivity due to a difference of the installation state; and
an output circuit configured to output information representing the sound emitted by the aquatic organism.
2. The aquatic organism observation device according to claim 1 , wherein the aquatic organism information detector is further configured to classify a kind of the aquatic organism or an action of the aquatic organism, from the information representing the sound emitted by the aquatic organism.
3. The aquatic organism observation device according to claim 2 , wherein the aquatic organism information detector is further configured to perform the classification by analogical determination in light of a previously held classification condition with one or more characteristics as a key.
4. The aquatic organism observation device according to claim 3 , wherein the characteristic being used for the classification includes at least one of a frequency, a temporal change of a frequency, and a temporal change of an intensity envelope of the sound data.
5. The aquatic organism observation device according to claim 2 , wherein the aquatic organism information detector is further configured to perform the classification after dividing the sound data into a plurality of frequency bands.
6. The aquatic organism observation device according to claim 1 , wherein the aquatic organism information detector is further configured to identify the sound data of the sound emitted from a same sound source, among pieces of the sound data acquired at a plurality of the positions of the optical fiber.
7. The aquatic organism observation device according to claim 6 , wherein the aquatic organism information detector is further configured to perform spatial separation of the sound source by use of, as a sensor array output, the sound data of the sound detected at a plurality of the positions of the optical fiber.
8. The aquatic organism observation device according to claim 6 , wherein the aquatic organism information detector is further configured to track the moving sound source by applying to a movement model.
9. The aquatic organism observation device according to claim 1 , wherein the aquatic organism information detector is further configured to perform processing of correcting, based on information about a kind of the optical cable stored in the storage, the sound data to reduce an influence of a sensitivity due to a difference of the kind.
10. The aquatic organism observation device according to claim 1 , wherein the aquatic organism information detector is further configured to perform processing of:
acquiring, by use of a reference sound transmitting in a wide range of the optical cable, a degree of a difference of sound data due to the position where the sound data have been acquired, and
correcting, based on information about the degree of the difference, the sound data to reduce a difference of a sensitivity due to the position where the sound data have been acquired.
11. The aquatic organism observation device according to claim 1 , wherein the optical cable is shared with another use by separating an optical fiber core wire, or separating wavelengths.
12. The aquatic organism observation device according to claim 1 , wherein acquisition of the sound data is performed by optical fiber sensing.
13. The aquatic organism observation device according to claim 12 , wherein the optical fiber sensing is distributed acoustic sensing.
14. The aquatic organism observation device according to claim 1 , wherein the water is sea, and the aquatic organism is a marine organism.
15. The aquatic organism observation device according to claim 1 , further comprising acquisition processor configured to acquire the sound data by the optical fiber and sending the acquired sound data to the aquatic organism information detector.
16. An aquatic organism observation system comprising: the aquatic organism observation device according to claim 1 ; and the optical fiber.
17. An aquatic organism observation method executed by an aquatic organism observation device including a storage storing information about a manufacturing or construction of an optical fiber provided in an optical cable, the method comprising:
detecting, from sound data being acquired by an optical fiber provided in the optical cable that is installed in water or at a bottom of water and being data relating to a sound at a predetermined position of the optical fiber, a sound emitted by an aquatic organism at a time and a place at which the sound data have been acquired;
identifying a sound emitted from a same sound source, among sounds detected at a plurality of positions of the optical fiber;
performing processing of correcting, based on information about an installation state of the optical cable stored in the storage, the sound data to reduce an influence of a sensitivity due to a difference of the installation state; and
outputting information representing the sound emitted by the aquatic organism.