done, the most common alternative techniques are digital scrambling, covering the prohibited area with a black box or a fuzzy white spot, known as a mosaic or "fogging". Some have claimed that it is this censorship that gives the Japanese erotic cinema its particular style. Richie wrote: Richie makes a distinction between the erotic films of the major studios such as Nikkatsu and Toei as against the low-budget pink films produced by independents such as OP Eiga. Contrasting the pink film with Western pornographic films, Pia Harritz says, "What really stands out is the ability of pinku eiga to engage the spectator in more than just scenes with close-ups of genitals and finally the complexity in the representation of gender and the human mind." Richie and Harritz enumerate the fundamental elements of the pink film formula as: The film must have a required minimum quota of sex scenes The film must be approximately one hour in duration It must be filmed on 16 mm or 35 mm film within one week The film must be made on a very limited budget History Background In the years since the end of World War II, eroticism had been gradually making its way into Japanese cinema. The first kiss to be seen in Japanese film—discreetly half-hidden by an umbrella—caused a national sensation in 1946. Although throughout the 1940s and early 1950s nudity in Japanese movie theaters, as in most of the world, was a taboo, some films from the mid-50s such as Shintoho's female pearl-diver films starring buxom Michiko Maeda, began showing more flesh than would have previously been imaginable in the Japanese cinema. During the same period, the taiyozoku films on the teen-age "Sun Tribe", such as Kō Nakahira's Crazed Fruit (1956), introduced unprecedented sexual frankness into Japanese films. Foreign films of this time, such as Ingmar Bergman's Summer with Monika (1953), Louis Malle's Amants (1958), and Russ Meyer's Immoral Mr. Teas (1959) introduced female nudity into international cinema, and were imported to Japan without problem. Nevertheless, until the early 1960s, graphic depictions of nudity and sex in Japanese film could only be seen in single-reel "stag films," made by film producers such as those depicted in Imamura's film The Pornographers (1966). First wave (The "Age of Competition" 1962–1971) The first wave of the pink film in Japan was contemporary with the similar U.S. sexploitation film genres, the "nudie-cuties" and "roughies". Nudity