A photographing device comprising: two or more lenses (410,420, 510, 520, 2211, 2212), each of the two or more lenses having different view angles; and a processor (120, 210) configured to: acquire images from the lenses, wherein the images comprise a first image (1910, 2010, 2410, 2420) which is acquired through a first lens and a second image (1210, 1310, 1920, 2020, 2440) which is acquired through a second lens different from the first lens, wherein a view angle of the first lens overlaps a view angle of the second lens, detect a first subject (20, 820, 920, 1020, 1410, 1510, 1711, 1712, 1810, 2220, 2450, 2520) based at least on the images from the first lens; detect a second subject (30, 1220, 1320, 1420, 1520, 1721, 1722, 1820, 2070) based on the images from the second lens; identify a kind of the second subject (30, 1220, 1320, 1420, 1520, 1721, 1722, 1820, 2070) and a movement type of the second subject based on the second images, read out pre-stored motion information corresponding to the kind of the second subject and the movement type of the second subject, determine, based on the pre-stored motion information, a speed and a movement direction of the second subject, determine, based on the speed and the movement direction of the second subject, whether the second subject approaches a view angle of the first image including the first subject among the images, and generate a notification signal (1441, 1442, 1443) based on the determination of whether the second subject approaches the view angle of the first image including the first subject among the acquired images. two or more lenses (410,420, 510, 520, 2211, 2212), each of the two or more lenses having different view angles; and a processor (120, 210) configured to: acquire images from the lenses, wherein the images comprise a first image (1910, 2010, 2410, 2420) which is acquired through a first lens and a second image (1210, 1310, 1920, 2020, 2440) which is acquired through a second lens different from the first lens, wherein a view angle of the first lens overlaps a view angle of the second lens, detect a first subject (20, 820, 920, 1020, 1410, 1510, 1711, 1712, 1810, 2220, 2450, 2520) based at least on the images from the first lens; detect a second subject (30, 1220, 1320, 1420, 1520, 1721, 1722, 1820, 2070) based on the images from the second lens; identify a kind of the second subject (30, 1220, 1320, 1420, 1520, 1721, 1722, 1820, 2070) and a movement type of the second subject based on the second images, read out pre-stored motion information corresponding to the kind of the second subject and the movement type of the second subject, determine, based on the pre-stored motion information, a speed and a movement direction of the second subject, determine, based on the speed and the movement direction of the second subject, whether the second subject approaches a view angle of the first image including the first subject among the images, and generate a notification signal (1441, 1442, 1443) based on the determination of whether the second subject approaches the view angle of the first image including the first subject among the acquired images. acquire images from the lenses, wherein the images comprise a first image (1910, 2010, 2410, 2420) which is acquired through a first lens and a second image (1210, 1310, 1920, 2020, 2440) which is acquired through a second lens different from the first lens, wherein a view angle of the first lens overlaps a view angle of the second lens, detect a first subject (20, 820, 920, 1020, 1410, 1510, 1711, 1712, 1810, 2220, 2450, 2520) based at least on the images from the first lens; detect a second subject (30, 1220, 1320, 1420, 1520, 1721, 1722, 1820, 2070) based on the images from the second lens; identify a kind of the second subject (30, 1220, 1320, 1420, 1520, 1721, 1722, 1820, 2070) and a movement type of the second subject based on the second images, read out pre-stored motion information corresponding to the kind of the second subject and the movement type of the second subject, determine, based on the pre-stored motion information, a speed and a movement direction of the second subject, determine, based on the speed and the movement direction of the second subject, whether the second subject approaches a view angle of the first image including the first subject among the images, and generate a notification signal (1441, 1442, 1443) based on the determination of whether the second subject approaches the view angle of the first image including the first subject among the acquired images.