A biometric authentication apparatus comprising: an imaging device; a display device; and a processor configured to display, on a screen of the display device, guidance indicating target areas to be in contact with two fingers of a human body, detect whether the two fingers are in contact with the target areas, when the two fingers are in contact with the target areas, determine a distance between the imaging device and a second part of the human body, the second part of the human body being a palm or a hand having the two fingers, in accordance with an image captured by the imaging device, the image being captured by the imaging device in a state in which the two fingers are in contact with the target areas and the image includes the second part of the human body, and when the distance is not suitable for capturing an image to be used for biometric authentication, perform a change of display positions of the guidance so that the distance between the changed display positions is to be suitable for capturing an image to be used for biometric authentication, characterised in that the distance is determined in accordance with a distribution of the frequency components of the image, wherein the image is converted into signals in a spatial frequency domain and a result of the conversion represents the distribution of the frequency components of the image. an imaging device; a display device; and a processor configured to display, on a screen of the display device, guidance indicating target areas to be in contact with two fingers of a human body, detect whether the two fingers are in contact with the target areas, when the two fingers are in contact with the target areas, determine a distance between the imaging device and a second part of the human body, the second part of the human body being a palm or a hand having the two fingers, in accordance with an image captured by the imaging device, the image being captured by the imaging device in a state in which the two fingers are in contact with the target areas and the image includes the second part of the human body, and when the distance is not suitable for capturing an image to be used for biometric authentication, perform a change of display positions of the guidance so that the distance between the changed display positions is to be suitable for capturing an image to be used for biometric authentication, characterised in that the distance is determined in accordance with a distribution of the frequency components of the image, wherein the image is converted into signals in a spatial frequency domain and a result of the conversion represents the distribution of the frequency components of the image. display, on a screen of the display device, guidance indicating target areas to be in contact with two fingers of a human body, detect whether the two fingers are in contact with the target areas, when the two fingers are in contact with the target areas, determine a distance between the imaging device and a second part of the human body, the second part of the human body being a palm or a hand having the two fingers, in accordance with an image captured by the imaging device, the image being captured by the imaging device in a state in which the two fingers are in contact with the target areas and the image includes the second part of the human body, and when the distance is not suitable for capturing an image to be used for biometric authentication, perform a change of display positions of the guidance so that the distance between the changed display positions is to be suitable for capturing an image to be used for biometric authentication, characterised in that the distance is determined in accordance with a distribution of the frequency components of the image, wherein the image is converted into signals in a spatial frequency domain and a result of the conversion represents the distribution of the frequency components of the image.