US 12,412,256 B2
Anomaly detection device, anomaly detection method, and computer program product
Naoki Kawamura, Yokohama Kanagawa (JP)
Assigned to KABUSHIKI KAISHA TOSHIBA, Tokyo (JP)
Filed by KABUSHIKI KAISHA TOSHIBA, Tokyo (JP)
Filed on Aug. 12, 2021, as Appl. No. 17/400,299.
Claims priority of application No. P2021-042811 (JP), filed on Mar. 16, 2021.
Prior Publication US 2022/0301140 A1, Sep. 22, 2022
Int. Cl. G06T 7/00 (2017.01); G06F 18/22 (2023.01)
CPC G06T 7/0002 (2013.01) [G06F 18/22 (2023.01)] 8 Claims
OG exemplary drawing
 
1. An anomaly detection device comprising:
at least one hardware processor configured to execute processes comprising:
calculating a difference in feature map output in an intermediate layer when each of one or more pieces of normal data included in a normal dataset and input data are input to a pre-trained convolution neural network (CNN) as an anomaly score map indicating a degree of anomaly of the input data, the input data and the normal data being photographed image data;
selecting, as reference data, one piece of the normal data which is included in the normal dataset and which is determined to have a photographing condition whose degree of similarity with a photographing condition of the input data is equal to or greater than a predetermined threshold value;
by using a difference in feature within the one piece of the normal data selected as the reference data, calculating a correction score map for correcting the anomaly score map, the calculated correction score map indicating a higher score as the difference in feature is greater;
correcting the anomaly score map by using the correction score map; and
displaying, on a display, a corrected anomaly score map that represents the anomaly score map corrected by using the correction score map.