11. The digital image processing method as recited in claim 10 , wherein said step of performing clothes recognition further includes performing clothes feature extraction for said clothes areas by extracting representative image patches from said clothes areas, quantizing said representative image patches using vector quantization to obtain patch vectors, clustering said patch vectors to obtain patch clusters and code-words as centers of said patch clusters, and representing said clothes areas by code-word feature vectors of frequencies of appearance of said code-words in said clothes areas.
10. The digital image processing method as recited in claim 1 , wherein said step of performing clothes recognition includes detecting clothes regions below faces of said plurality of persons, segmenting clothes regions by maximizing a difference between said clothes regions to determine clothes areas, and removing clutters not belonging to said clothes areas.