Several major producers last week were making their pitches to shoot a movie based on the erotic bestseller, “Fifty Shades of Grey,” even as “Fifty Shades” products ranging from lingerie to sleepwear are poised to hit retailers.

It’s intriging to see filmmakers like Michael De Luca, Brian Grazer and Nina Jacobson, among others, making their presentations to a once-obscure author like E.L. James — she’s really Erika Leonard, a middle-aged British mom with a rich fantasy life. Members of the billionaire ladies club like Stephenie Meyer (“Twilight”), J.K. Rowling (“Harry Potter”) or Deborah Harkness (“Shadow of Night”) must be startled to see whips-and-chains erotica moving in on their vampires, witches and wizards.

Still, the “Fifty Shades” trilogy has sold more than 1 million copies on Kindle alone and as smart a guy as James Schamus, who heads Focus Features, believes so deeply that sex sells he may even write the screenplay himself. He’ll have to overcome the doubts of folks like Camille Paglia, the author of “Sexual Personae,” who warns, “Hollywood has turned women into cartoonishly pneumatic superheroines and sci-fi androids — fantasy figures without psychological complexity.”

One problem facing filmmakers is that they don’t have as much information about the tastes of filmgoers as do publishers of e-books. Digital publishers are now tracking how fast their books are being read and which sections are skipped or highlighted. Barnes and Noble tracks its Nook e-readers to find out which genres are favored and by whom. Amazon, which is both a retailer and a publisher, is especially diligent about gathering data and, some authors fear, may even start telling authors whether the endings to their books work for readers or should be rewritten.

Since Nook readers are found to be impatient with overlong nonfiction books, the company has launched Nook Snaps — shorter works in which journalists probe more focused topics of contemporary interest.

The advantage of the digital-book business is that it is dominated by three companies — Amazon, Apple and Google — and book apps give them reliable maps of reader interest.

All this would surely be helpful to whoever ends up shooting the “Fifty Shades” books. When Christian whips off his belt and Anastasia pleads, “Punish me, I want to know how bad it can get,” do readers become more engrossed or simply ask themselves why they’re reading about sex instead of sorcery?

E.L. James, who invented the “Fifty Shades” franchise, once worked in TV development and wrote fan fiction under the name of Snowqueen Icedragon. She acknowledges that writing “Fifty Shades” helped resolve her “midlife crisis,” never expecting that her S&M chronicles would land her on Time’s list of the 100 Most Influential People in the World.

While she earns a reported million dollars week, she’s admitted in interviews that her books have done little to spice up her own life and she won’t let her teenage sons read the books.

Inevitably, “Saturday Night Live” has had a field day with “Fifty Shades,” which has billed “mommy porn” as the ideal Mother’s Day gift. Kristen Wiig is usually the Mommy discovered reading in the bathtub by her teenage sons.

So will the “Fifty Shades” lingerie sell? Will the character of Anastasia in the film be another “sci-fi android?”

I somehow don’t feel Stephenie Meyer, J.K. Rowling or Deborah Harkness should feel threatened. Nor should their inhouse wizards and sorcerers.