Method of processing images using high dynamic range while preserving frame rate and image processing device performing the same

In a method of processing an image which is a video image including a plurality of frame images, a first high dynamic range (HDR) image is generated by combining a first frame image and a second frame image subsequent to the first frame image. The first and second frame images are included in the plurality of frame images. The first frame image has a first exposure time. The second frame image has a second exposure time different from the first exposure time. A second HDR image is generated by combining the second frame image and a third frame image subsequent to the second frame image. The third frame image is included in the plurality of frame images and has the first exposure time.