BUENOS AIRES — Already Latin America’s biggest film market, Ventana Sur has just got bigger.

Through Tuesday, three days out from Friday’s get-go, total accreditations for the 4th edition were 1,844, already 7% up on final figures last year, with a strong increase in Latin Americans from outside Argentina, said Ventana Sur co-director Jerome Paillard.

That hike hardly comes as a surprise.

Since its inaugural 2009 edition, Ventana Sur’s organizers, Argentina’s Incaa Film Institute and Cannes Film Festival’s Market, have attracted large numbers of foreign sales agents, film distributors and TV buyers unprecedented in Latin American history. Attracted by this critical mass, a galaxy of satellite events now revolve around Ventana Sur.

Latin America’s market is booming. In 2011, Latin American B.O. grew 16% to $2.3 billion, driven by multiplexing and the disposable income of new middle classes, said Screen Digest.

Argentina’s B.O. spiked 25% in the first half of this year, the second biggest rise in the world after China’s.

Local industries are more ambitious about grabbing larger shares of local and international markets: Three of the best-selling recent Latin American titles — all at Ventana Sur — Pablo Larrain’s “No,” Pablo Trapero’s “White Elephant” and Juan Jose Campanella’s $20 million animation “Foosball” — are all conscious step-ups in scale for their directors.

Netflix’s launch in Latin America and aggressive play for the first pay TV window is galvanizing regional pay TV prices, hence attracting sellers.

Ventana Sur’s build also reflects the second-wave growth of the smaller Latin American countries. Some 87 film pros, mostly young producers, travel to Ventana Sur from Chile. Ecuador, which brings 16 film companies, will soon be making eight to 10 features a year, a production hike driven by state aid and a new generation of filmmakers, said Jorge Luis Serrano, at Ecuador’s Consejo Nacional de Cinematografia state film board.

Latin America now offers “an increasingly diverse and prolific output of films and powerful new filmmakers who generationally have a more global perspective on the filmmaking process,” said IM Global CEO Stuart Ford.

He added: “Mexico, Brazil and Argentina have always provided a solid base, but now we’re seeing financing and filmmakers sprouting from countries like Chile, Venezuela and Colombia.

The most logical reaction to Latin America’s burgeoning film scene is simply to seek greater involvement.

The U.S., with 47 companies, has nearly as big a national presence as France, with 57. U.S. companies attending include IM Global, which announced Wednesday a new Mexico City-based joint venture, Mundial, to finance and sell Latin American films.

While its core is still a screenings market, Ventana Sur co-production heft is growing. Launching this year at Ventana Sur, Cannes Market’s Producers Network expected about 100 producers. It has attracted 219.

Multiple potential mart highlights await them.

Campanella (“The Secret in Their Eyes”) unveils Saturday six-to-eight minutes of “Foosball,” at $20 million Latin America’s biggest animated movie ever. Sales agent Film Factory has just sold Poland to Iti Cinema, adding to weighty deals with UIP — for Argentina, the rest of Latin America and Spain — and Russia’s Carmen Films, among major territories.

FilmSharks Intl. will host Friday an invitation-only screening of Israel Adrian Caetano’s kick-ass femme actioner “Mala,” about a hit-woman in love, one of Disney’s big Argentine bets for 2013.

Some 134 completed films screen. Once limited to the six-pic Primer Corte, chosen this year by Cinefondation’s Georges Goldenstern, Ventana Sur has added two more pix-in-post showcases: A works in progress presentation on Friday from Argentina’s Independent Film Project, and a digital library VIP strand for fest-heads of other pix in post, of which there’s a good buzz on Jose Luis Valle Gonzalez’s Mexico-produced “Workers” and Argentinian Gustavo Garzon’s “Just for a While.”

Mexico’s Imcine and Brazil’s Cinema do Brasil will showcase recent production showreels; Cinemachile announces a major industry initiative Sunday.