LEARNING APPARATUS, LEARNING METHOD AND LEARNING PROGRAM

1 . A learning apparatus comprising:

a memory including a first model and a second model; and

a processor configured to execute:

causing the first model to accept a plurality of frame images included in a video as input, and output a feature vector for each frame image;

causing the second model to accept the feature vector for each frame image as input, and output a temporal interval between a frame image treated as a reference and each of the frame images other than the frame image treated as the reference; and

updating parameters of the first and second models such that each of the temporal intervals output from the second model approaches each temporal interval computed from time-related information pre-associated with each frame image.

2 . The learning apparatus according to claim 1 , wherein the processor is further configured to execute:

changing a temporal sequence of the frame images,

generating information indicating a time difference or a difference in a frame ID between the frame image treated as the reference being a first frame image in the temporal sequence, and each of a second frame image and subsequent frame images among the frame images, and

storing in the memory information indicating each time difference or difference in the frame ID in association with the frame images for which the temporal sequence has been changed,

causing the first model to accept each frame image stored in the memory as input, and output a feature vector of each frame image, and

updating the parameters of the first and second models such that the information indicating each time difference or difference in the frame ID output from the second model approaches the information indicating each time difference or difference in the frame ID stored in association with each frame image in the memory.

3 . The learning apparatus according to claim 2 , wherein the processor is further configured to execute causing the first model to accept a plurality of frame images included in the video and either or both of sensor data associated with each frame image or information related to an object included in each frame image as input, and output the feature vector for each frame image.

4 . A learning method executed by a computer including a memory including a first model and a second model, and a processor, the learning method comprising:

causing the first model to accept a plurality of frame images included in a video as input, and output a feature vector for each frame image;

causing the second model to accept the feature vector for each frame image as input, and output a temporal interval between a frame image treated as a reference and each of the frame images other than the frame image treated as the reference; and

updating parameters of the first and second models such that each of the temporal intervals output from the second model approaches each temporal interval computed from time-related information pre-associated with each frame image.

5 . A non-transitory computer-readable recording medium having computer-readable instructions stored thereon, which when executed, cause a computer including a memory including a first model and a second model, and a processor to execute a learning process comprising:

causing the first model to accept a plurality of frame images included in a video as input, and output a feature vector for each frame image;

causing the second model to accept the feature vector for each frame image as input, and output a temporal interval between a frame image treated as a reference and each of the frame images other than the frame image treated as the reference; and

updating parameters of the first and second models such that each of the temporal intervals output from the second model approaches each temporal interval computed from time-related information pre-associated with each frame image.