Porno gets little respect as a film genre in the West, with its makers relegated to a ghetto that few escape. How many A-list directors in Hollywood, past or present, started by making even the milder sort of sex stuff seen on cable?

In Japan, however, the situation has been quite different, as Jasper Sharp's excellent, exhaustive study "Behind the Pink Curtain: The Complete History of Japanese Sex Cinema" makes clear. Many of the leading directors in the Japanese film industry today, especially those who entered it after the studio system collapsed in the early 1970s, learned their craft in the porno industry.

One is Masayuki Suo, whose 1984 "Hentai Kazoku: Aniki no Yome-san" ("Abnormal Family: Older Brother's Bride") is a porno parody in the style of Yasujiro Ozu. Suo went on to direct "Shall We Dance?" (1995), a dramedy about a salaryman who takes up ballroom dancing that became the most popular Japanese live-action film ever released in the United States. Another is Yojiro Takita, who made a series of soft-core comedies about commuter train molesters in the 1980s, but went on a mainstream career that has culminated with "Okuribito" ("Departures"), a hit drama about an apprentice undertaker that is Japan's nominee this year for a Best Foreign-Language Film Oscar.