1. A non-transitory computer-readable recording medium having stored therein a program causing a computer to execute a category creating process comprising: receiving a piece of music; extracting video image information that is included in the music received at the receiving and decomposing the extracted video image information with respect to each characteristic of the extracted video image information; measuring an appearance time during which a characteristic appears in the music; associating, by referring to a characteristic storing unit which stores the characteristic and a plurality of categories that represent the characteristic in an associated manner, the appearance time measured at the measuring with the plurality of categories which are stored in the characteristic storing unit; and calculating a total time at which each category appears in the music.
2. The non-transitory computer-readable recording medium according to claim 1 , further comprising: extracting character information from the video image information included in the music that is received at the receiving; and decomposing the character information extracted at the extracting into words, wherein the associating includes specifying, by referring to a word storing unit which stores the plurality of categories which are stored in the characteristic storing unit and at least one word in an associated manner, a category that is associated with a word.