Method of operating image processor generating top-down heat map and electronic device having the image processor

An operating method of an image processor communicating with a memory device, the method comprising:

• receiving raw image data from the memory device;
• receiving first to n-th filter data from the memory device;
• generating first to n-th heat maps based on a convolution neural network (CNN) operation of the first to n-th filter data and the raw image data;
• extracting a first region of interest (ROI) from a first heat map among the first to n-th heat maps, wherein the first heat map is generated by sequentially applying n-th to first filter data to the raw image data;
• extracting a first portion from a second heat map among the first to n-th heat maps, the first portion corresponding to the first ROI, wherein the second heat map is generated by sequentially applying n-th to second filter data to the raw image data;
• and
• generating a first top-down heat map by applying the first portion of the second heat map to the first ROI of the first heat map,
• wherein ‘n’ is a natural number greater than ‘2’.