1. A method of processing image data, comprising: receiving compressed image data; decompanding the compressed image data; extracting long-exposure image data from the decompanded image data; performing pre-processing on the long-exposure image data; extracting short-exposure image data from the decompanded image data; performing pre-processing on the short-exposure image data; merging the pre-processed long-exposure image data with the pre-processed short-exposure image data; and performing tone mapping on the merged image data.