TORONTO—Folk legend Joni Mitchell says she's started writing "vignettes" for an autobiography, but has put an end to a planned film about her life.

"They were going to make this movie about me, which I squelched. Thank God I squelched it," Mitchell revealed Sunday during an onstage Q&A with New York Times chief pop music critic Jon Pareles at the Luminato arts festival.

"I called the producer ... and I said, 'If you're going to make this movie, it's going to be a piece of (rubbish) ... because you don't have any of the great scenes,'" said Mitchell, using an unprintable expletive.

The 69-year-old singer/songwriter is notoriously media-shy, but candidly discussed her life and work during the chat at the 500-seat Isabel Bader Theatre, where she was accompanied by her longtime drummer/bandleader Brian Blade.

Born in Fort Macleod, Alta., and raised in Saskatchewan, Mitchell said her mother had the mumps while pregnant. As a result, the singer said she was left with "anomalies," including a left hand with "tricky knuckles" that "just didn't work well" and polio, which she said took away her athletic ability and popularity.

"So that helped to make the transformation, I think, to an inner life and to an artistic life," said Mitchell, who has a home in Los Angeles.

Ultimately, Mitchell taught herself guitar, took piano lessons and began to play music by ear.

"My (music) education really was that I got to play with musicians of such stellar ability, with such great musicians. You couldn't get that in school," she said. "So you can't really say I'm uneducated, but I'm strong-willed. I'm like a Jack Russell, I'm going to do it the way I'm going to do it."

Wearing a black dress and black boots and her flaxen-hair up in a loose bun, Mitchell started by discussing her early career, when she moved to Toronto to pursue folk music but had to "disappear" from the stage because she got pregnant with a girl she gave up for adoption.

She admitted she didn't like the "nasally" vocal period she was going through on her second and third albums, CLOUDS and LADIES OF THE CANYON, which became her first gold record with the celebrated tunes Big Yellow Taxi, Woodstock and The Circle Game.

"And then (the LP) BLUE, that all assimilates into a kind of a pop/rock 'n' roll voice out of vibrato and semi-classical singing," said Mitchell, who lit up a cigarette at one point in the talk and admitted she doesn't have the vocal range she once did.

The raw honesty on BLUE, which includes the hits River and A Case Of You, "horrified" the men in the singer-songwriter community, she noted.

"Because it was unprecedentedly intimate. It made the men very uncomfortable," said Mitchell. "But later their work also went a little deeper, you know, Neil (Young's) did, Kris Kristofferson's did. I don't remember Neil's reaction. Kris was kind of horrified by it, Johnny Cash was kind of horrified by it. And it didn't sell well at first. It was over time that people came to it.

"So it was kind of like rubber-necking a car accident."

Mitchell said that time period may have been when she started developing Morgellons syndrome, noting things made her "very sad" and depressed, and she felt she had to share that with her audience.

"I'd look at things and weep and also I seemed to have powers coming in where I could see through people and I didn't really want to," said the spiritual Mitchell. "I thought I had the evil eye and I thought they could see through me. And also, I was developing an audience and I didn't want to have a phoney relationship with my audience."

Mitchell is slated to perform at Luminato's "Joni: A Portrait in Song—A Birthday Happening Live at Massey Hall" on Tuesday and Wednesday. She'll recite a new poem inspired by Emily Carr with musical accompaniment from Blade and trumpeter Ambrose Akinmusire.

Other artists in the lineup for the concerts, which will mark Mitchell's 70th birthday in November, include 14-time Grammy winner Herbie Hancock, jazz singer Esperanza Spalding, and Montreal-raised musician Rufus Wainwright.

Mitchell said she still spends half the year in Canada (she has a home on British Columbia's Sunshine Coast), where she writes and restores her soul.

"When I was a kid in Battleford, (Sask.), and I was having problems one way or another relating, I would get on my bike, grab my smokes and sit in the bush and watch birds fly in and out.

"And that's always been a part of my need, is to be alone in the wild, or seemingly the wild."