Device and method for detecting position of island in melting furnace

The present invention relates to an island position detection device capable of quickly and accurately detecting a position of an island on the surface of a molten material flowing in a melting furnace. A control means of the present invention: derives a plurality of first singular points associated with temperature or brightness in an image of the surface of the melting furnace, photographed by a photographing means; transforms the plurality of first singular points on the image into lines of virtual parameter coordinates by Hough transform, and then obtains a plurality of intersection points where the lines intersect; obtains a plurality of second singular points forming a peak on the virtual parameter space, among intersection points expressed in a virtual parameter space, which has ρ and θ axes forming the virtual parameter coordinates and axes associated with the number of intersection times as axes perpendicular to the respective ρ and θ axes; derives the plurality of second singular points into a plurality of connection lines by inverse Hough transform; and selects a position of an island on the basis of the plurality of connection lines.