Every year new film festivals launch in Scotland, a process replicated tenfold across the UK and beyond. The latest addition to the family is notable for having one of the most pleasing acronyms on the circuit – it's pronounced “skwiff” – but what really marks it out is the fact it contains something many other film festivals claim to but rarely do: different voices offering different world views, and characters whose stories take place in communities outside the mainstream.

The inaugural Scottish Queer International Film Festival (SQIFF) opens at Glasgow's CCA on Thursday with a screening of camp Swedish film Dyke Hard, a John Waters-style genre mash-up about a failed lesbian rock group. It closes on September 27 with Do I Sound Gay?, a documentary by Canadian journalist David Thorpe in which he examines cultural attitudes to the “gay voice”. In between are four days of screenings at venues across the city covering all aspects of life for people who describe themselves as lesbian, gay, bisexual or transgender/transsexual – or LGBT, to use the now-familiar shorthand.

The festival is the brainchild of 33-year-old Glasgow-based filmmaker Helen Wright. The idea itself came after a visit to the 2014 London LGBT Film Festival.

“I saw so many films there that I knew wouldn't get screened in Scotland normally, so when I came back I contacted some other people who were involved in queer art events and we talked about putting on a festival here,” she explains. “But I suppose the idea is really to increase the opportunities for people to see queer films, which were a bit limited in Scotland previously.”

Wright defines “queer” films two ways. Firstly, those which explicitly feature LGBT characters or storylines. Secondly, more mainstream films which have a “queer” subtext either put there deliberately as an under-the-radar motif for the keen-eyed, or unwittingly by directors who must wonder why their films subsequently acquire a sort of cult status.

Examples of the second would be The Wizard Of Oz (screenwriter Edgar Allan Woolf was a friend of Dorothy in every sense: a “wild, red-haired homosexual” according to MGM producer Samuel Marx) and 1986 smash Top Gun. As Quentin Tarantino's character suggests in 1994 rom-com Sleep With Me, deliberate or not Tony Scott's action film is “subversion on a massive level… a story about a man's struggle with his own homosexuality.”

Neither of those films are in the SQIFF line-up (yet), but Johnny Guitar is. Released in 1954 and directed by the bisexual Nicholas Ray, it stars women in the main roles – Mercedes McCambridge and a gun-toting, trouser-wearing, saloon bar-owning Joan Crawford – and was once described by film critic Roger Ebert as “one of the most blatant psycho-sexual melodramas ever to disguise itself in that most commodious of genres, the western”.

Other more mainstream SQIFF offerings include Pedro Almodovar's 1984 film What Have I Done To Deserve This?, gender-blurring Japanese anime Ghost In The Shell, and Maleficent, a baroque re-imagining of Sleeping Beauty starring Angelina Jolie as the baddie from the 1959 Disney version. And what queer film festival worth its salt could ignore John Waters himself? His 1977 film Desperate Living screens in the Lock Up Your Mothers strand.

With America finally joining the many other countries which have legalised gay marriage, and TV shows such as Transparent and BBC Two's Boy Meets Girl at last giving voice to trans characters, it's clear the mainstream is taking some note of LGBT issues. But as Elton John highlighted last weekend in comments made after addressing the YES Ukraine conference, LGBT communities in that country and in neighbouring Russia still face prejudice. Unsurprisingly, Wright thinks there's more to be done, and much more to be said by LGBT filmmakers.

“When the media and mainstream culture foregrounds gay marriage, a lot of other issues get buried, so I'd like to think that we are probing various aspects of queer culture which are still not hugely accepted in the mainstream.”

Accordingly SQIFF is showing films such as Alive!, a French film about five men's experience of living with HIV ("something that still doesn't really get talked about, remarkably, even though it has been an issue for a while” ); a series of provocative films on the subject of transgender; and shorts about sexuality and disability made by the Sins Invalid co-operative and showing under the banner Queer Activism. There's also a chance to dip into the oeuvre of Campbell X, a black lesbian filmmaker from London whose debut feature, Stud Life, was made for around £5000 and who prefers to be described using the gender-neutral “they” rather than “she”.

But perhaps the most headline-grabbing event is the one devoted to Feminist Porn, which Wright describes as a “representation of sex which empowers women and queer people and which asks questions about the mainstream pornographic language”. And yes, there will be examples, drawn largely from Sweden and Berlin where the LGBT scene has a well-established cultural and political dimension in which the more provocative filmmakers are quite happy to tackle pornography. Screening at the CCA on Thursday, it also features a discussion with directors Maja Borg, Herrera Catalá and Marit Östberg.

“I think sex in general, actually, is something which gets buried when you move onto things like gay marriage and gay people integrating into mainstream heterosexual culture,” says Wright.

SQIFF aims to remedy that, though at the same time Wright makes no bones about wanting to reach out to Scotland's wider cinema-going public, both in terms of demographics and geography. The newest member of the country's film festival family could soon prove to be the most radical and challenging of the lot.

The Scottish Queer International Film Festival opens on Thursday and runs until September 27 at venues across Glasgow including the CCA, Glasgow Women's Library, Andrew Stewart Cinema and The Glad Cafe

www.sqiff.org