A method of generating metadata including frequency characteristic information of an image, the method comprising: converting pixel values of a current block among blocks divided from the image into frequency coefficients in a frequency domain; determining a band value of a frequency band corresponding to each of regions of the current block by using the frequency coefficients included in the regions of the current block, the regions of the current block being divided to correspond to different frequency bands; and generating metadata including the frequency characteristic information of the current block based on the determined band values; wherein the determining of the band value of the frequency band corresponding to each of the regions of the current block comprises: grouping the frequency coefficients of the current block into groups corresponding to m frequency bands using a predetermined frequency band pattern which includes m frequency bands, wherein m is a natural number; evaluating the frequency coefficients belonging to each of the groups by comparing a statistic of the frequency coefficients belonging to each of the groups with a threshold value allocated to the frequency band of each of the groups; and determining the band values based on a result of evaluating the frequency coefficients belonging to each of the groups, characterized by: the determining of the band value of the frequency band corresponding to each of the regions of the current block comprises generating an m-digit bit string having bits corresponding to the m band values, and frequency characteristics of the current block are expressed as a scalar value in the range 0 to 2 m -1 calculated from the m-digit bit string. converting pixel values of a current block among blocks divided from the image into frequency coefficients in a frequency domain; determining a band value of a frequency band corresponding to each of regions of the current block by using the frequency coefficients included in the regions of the current block, the regions of the current block being divided to correspond to different frequency bands; and generating metadata including the frequency characteristic information of the current block based on the determined band values; wherein the determining of the band value of the frequency band corresponding to each of the regions of the current block comprises: grouping the frequency coefficients of the current block into groups corresponding to m frequency bands using a predetermined frequency band pattern which includes m frequency bands, wherein m is a natural number; evaluating the frequency coefficients belonging to each of the groups by comparing a statistic of the frequency coefficients belonging to each of the groups with a threshold value allocated to the frequency band of each of the groups; and determining the band values based on a result of evaluating the frequency coefficients belonging to each of the groups, characterized by: the determining of the band value of the frequency band corresponding to each of the regions of the current block comprises generating an m-digit bit string having bits corresponding to the m band values, and frequency characteristics of the current block are expressed as a scalar value in the range 0 to 2 m -1 calculated from the m-digit bit string. grouping the frequency coefficients of the current block into groups corresponding to m frequency bands using a predetermined frequency band pattern which includes m frequency bands, wherein m is a natural number; evaluating the frequency coefficients belonging to each of the groups by comparing a statistic of the frequency coefficients belonging to each of the groups with a threshold value allocated to the frequency band of each of the groups; and determining the band values based on a result of evaluating the frequency coefficients belonging to each of the groups, characterized by: the determining of the band value of the frequency band corresponding to each of the regions of the current block comprises generating an m-digit bit string having bits corresponding to the m band values, and frequency characteristics of the current block are expressed as a scalar value in the range 0 to 2 m -1 calculated from the m-digit bit string. the determining of the band value of the frequency band corresponding to each of the regions of the current block comprises generating an m-digit bit string having bits corresponding to the m band values, and frequency characteristics of the current block are expressed as a scalar value in the range 0 to 2 m -1 calculated from the m-digit bit string.