A lens dirtiness detection apparatus configured to detect a transparent lens dirtiness of a camera , comprising: a control unit ; and a memory coupled to the control unit , wherein the memory stores therein pixel value data of an image captured by the camera , and wherein the control unit is characterized in that it is configured to: divide the image into a plurality of first regions of a predetermined image size; calculate image frequency powers for each of the plurality of first regions of the image based on pixel value data of the pixels situated within the corresponding first region; calculate the average image frequency power for each of the plurality of first regions of the image based on the image frequency powers calculated for the corresponding first region; determine whether each of the average image frequency powers of the plurality of first regions exceeds a predetermined first threshold or not; determine presence of a transparent lens dirtiness of the camera if the number of the first regions in which the image frequency power does not exceed the first threshold value exceeds a predetermined second threshold and otherwise determine absence of a transparent lens dirtiness of the camera; and output the determination result on presence or absence of a transparent lens dirtiness. a control unit ; and a memory coupled to the control unit , wherein the memory stores therein pixel value data of an image captured by the camera , and wherein the control unit is characterized in that it is configured to: divide the image into a plurality of first regions of a predetermined image size; calculate image frequency powers for each of the plurality of first regions of the image based on pixel value data of the pixels situated within the corresponding first region; calculate the average image frequency power for each of the plurality of first regions of the image based on the image frequency powers calculated for the corresponding first region; determine whether each of the average image frequency powers of the plurality of first regions exceeds a predetermined first threshold or not; determine presence of a transparent lens dirtiness of the camera if the number of the first regions in which the image frequency power does not exceed the first threshold value exceeds a predetermined second threshold and otherwise determine absence of a transparent lens dirtiness of the camera; and output the determination result on presence or absence of a transparent lens dirtiness. divide the image into a plurality of first regions of a predetermined image size; calculate image frequency powers for each of the plurality of first regions of the image based on pixel value data of the pixels situated within the corresponding first region; calculate the average image frequency power for each of the plurality of first regions of the image based on the image frequency powers calculated for the corresponding first region; determine whether each of the average image frequency powers of the plurality of first regions exceeds a predetermined first threshold or not; determine presence of a transparent lens dirtiness of the camera if the number of the first regions in which the image frequency power does not exceed the first threshold value exceeds a predetermined second threshold and otherwise determine absence of a transparent lens dirtiness of the camera; and output the determination result on presence or absence of a transparent lens dirtiness. <EOS>