Louis de Rochemont, 79 the Academy Award-winning movie producer who was a co-founder of the March of Time documentary series and emphasized realism in several highly acclaimed feature films, died Saturday in a nursing home in York, Maine.

Begun in the 1930s. The March of Time series, which Mr. de Rochement preferred to call "nonfiction" films, expanded the horizons of the early newsreel, and was conceived as a means of using the movies to show not merely what happened, but also why.

Mr. de Rochemont, the first producer of the series, and Roy E. Larsen, the Time inc, executive with whom he developed plans for the series shared an Academy Award for contributions to the newsreel form.

Another Oscar went to Mr. de Rochement for "The Fighting Lady," a celebrated and much-praised documentary of life aboard an aircraft carrier in the Pacific during World War II.

Adm. Chester Nimitz called the film, which Mr. de Rochement produced for 20th Century Fox, "a real picture of real men and real fighting."

Noted for the semi-documentary style he brought to the commercial Hollywood feature, Mr. de Rochemont produced several widely hailed films after the war that combined drama and realism.

Based generally on current or recent events, films include "The House on 92d Street," "13 Rue Madelaine," "Boomerang!" and "Lost Boundaries."

Release in 1949, "Lost Boundaries," whichreceived 11 major film awards, was one of the most controversial movies of its period, dealing with a black family and the question of racial identity.

It sprang from his meeting in 1947 with a college student who had just learned that the was of black ancestry. The student and his family had been living as whites for 20 years.

A magazine article on the family's experiences became the basis for "Lost Boundaries," which Mr. de Rochement produced independently after a major studio rejected the idea.

Faced in recent decades with the competition of television, Hollywood has accentuated the trend toward realism. Mr. de Rochment was one of the pioneers of the trend.

"Lost Boundaries" was made on location in small towns in New Hampshire and Maine.

"The essence of good drama," he said, "is an illusion of reality. Shotting in real places is the best way to get that illusion."

A native of Chelsea, Mass., Mr. de Rochemont grew up in Winchester, Mass., and was from boyhood fascinated by film making. At the age of 12 he build a camera, took "newsreels" on local streets and sold them to theaters.

After studying at Harvard in a Naval Cadet program, he was commissioned a Naval Officer in 1917 and served until resigning in 1923 to roam the world, making newsreels.

He was director of short subjects production for Fox from 1929 until 1934 when he began "The March of Time."

In addition to his wife, Virginia, who wrote the screenplay of "Lost Boundaries," survivors include a son, Louis @III of Toronto, a daughter, Virginia Mcreel, of Newport, R. I, a brother and six grandchildren.