A system comprising a video signature extraction device for extracting a video signature from a first video and a video signature from a second video, and a matching device for matching between the first video and the second video using the video signatures, the video signature extraction device comprising: a frame signature extraction unit that extracts a first frame signature from a video frame in the first video and a second frame signature from a video frame in the second video, wherein the frame signature extraction unit calculates a value, with respect to each of one or more dimensions, of each of the first and second frame signatures using a difference between features of two sub-regions associated with said dimension, and a confidence value calculation unit that calculates, for the video frame of the first video, a first confidence value of the first frame signature, and calculates, for the video frame of the second video, a second confidence value of the second frame signature, wherein the first confidence value of the first frame signature is a value from a predetermined minimum value to a predetermined maximum for the entire first frame signature, the first confidence value representing a certainty of a matching result when the video signature matching device performs matching using the first frame signature between the corresponding video frame and a video frame of the second video, the second confidence value of the second frame signature is a value from the predetermined minimum value to the predetermined maximum for the entire second frame signature, the second confidence value representing a certainty of a matching result when the video signature matching device performs matching using the second frame signature between the corresponding video frame and a video frame of the first video, the confidence value calculation unit is configured to calculate, if the video frame is a particular pattern, a confidence value, as each of the first confidence value and the second confidence value, that is smaller compared to a case in which the video frame is other than the particular pattern, and the particular pattern is of a video frame having uniform luminance values or having a variance of luminance values that is equal or lower than a threshold, the matching device comprising: a matching parameter calculation unit that calculates a matching parameter based on the first confidence value and the second confidence value, and a matching unit that performs matching between the first frame signature and the second frame signature based on the matching parameter. a frame signature extraction unit that extracts a first frame signature from a video frame in the first video and a second frame signature from a video frame in the second video, wherein the frame signature extraction unit calculates a value, with respect to each of one or more dimensions, of each of the first and second frame signatures using a difference between features of two sub-regions associated with said dimension, and a confidence value calculation unit that calculates, for the video frame of the first video, a first confidence value of the first frame signature, and calculates, for the video frame of the second video, a second confidence value of the second frame signature, wherein the first confidence value of the first frame signature is a value from a predetermined minimum value to a predetermined maximum for the entire first frame signature, the first confidence value representing a certainty of a matching result when the video signature matching device performs matching using the first frame signature between the corresponding video frame and a video frame of the second video, the second confidence value of the second frame signature is a value from the predetermined minimum value to the predetermined maximum for the entire second frame signature, the second confidence value representing a certainty of a matching result when the video signature matching device performs matching using the second frame signature between the corresponding video frame and a video frame of the first video, the confidence value calculation unit is configured to calculate, if the video frame is a particular pattern, a confidence value, as each of the first confidence value and the second confidence value, that is smaller compared to a case in which the video frame is other than the particular pattern, and the particular pattern is of a video frame having uniform luminance values or having a variance of luminance values that is equal or lower than a threshold, the matching device comprising: a matching parameter calculation unit that calculates a matching parameter based on the first confidence value and the second confidence value, and a matching unit that performs matching between the first frame signature and the second frame signature based on the matching parameter. a matching parameter calculation unit that calculates a matching parameter based on the first confidence value and the second confidence value, and a matching unit that performs matching between the first frame signature and the second frame signature based on the matching parameter.