European scene; Family Sayings, by Natalia Ginzburg. Manchester and New York: Carcanet Press. Revised from original translation by D.M. Low. 181 pp. $14.95.

Imagine a black-and-white movie camera set up in a rather shabby middle-class apartment in Turin. Natalia Ginzburg has written a documentary film script about her life in the '20s, '30s, '40s, and '50s in Italy. John Cassavetes, of the cinema verite school of ''realistic'' filmmaking, is directing - in the weird, funny, flamboyantly Italian style of Federico Fellini.

The characters include a tyrannical, volcanic-tempered professor of a father, a fey, good-hearted, optimistic eccentric of a mother, their three downtrodden sons, and their two repressed daughters, the younger of whom is Natalia herself.

It's neither a romantic nor a picturesque film. It's noisy, messy, emotional, painful, funny, and exasperating - the way life often seems to be.

Reading Natalia Ginzburg's ''Family Sayings'' is like watching such a movie. It was written in 1963 by one of the foremost Italian writers of this century and is considered to be her masterpiece. That is one very good reason for Carcanet Press to have reissued it this year, as the only book of hers so far published in English. Another good reason for choosing this one of her more than 20 published works is that it provides its readers with a series of intimate, telling close-ups of the turbulent times and place in which this important writer has lived.

From ''Family Sayings'' we learn, not only about Natalia Ginzburg and her family, but about Italy and the political convulsions it has experienced in this century. And the atmosphere the book evokes is so clear and immediate that reading it is like being there, or like seeing it on film.

The family goes about its business, and the camera rolls. We soon discover that the father is a socialist, a staunch antifascist, at a time when fascism is the order of the day. Trouble is, with his overbearing temperament, prejudices, and dictatorial behavior, he is in fact as fascist as Mussolini himself.

Observed by Ginzburg's cameralike eye, the family lumbers down the years with the wry humor and brooding eccentricity of an Italian version of ''You Can't Take It With You.'' But what Natalia Ginzburg has written is what actually happened, much of it deadly serious. Imperceptibly, the children are drawn into adulthood - into a period of university studies and marriages, of political activism, exile, and prison sentences.

Watching them along the way, we meet some of the most influential Italians of the time. Filippo Turati, founder of Italian Socialism, is hidden in the family's home as he makes his escape from Italy, endangering them all. Adriano Olivetti, son of the typewriter king, is a disheveled, benevolent radical who marries - and then divorces - Natalia's sister Paola. And later in the book, the prominent author Cesare Pavese, a brilliant, maddening, and tragic figure, holds a special place in Natalia's heart and in the famous antifascist publishing house, Einaudi, where she works.

The reader develops an odd relationship with this book, because he cannot forget that it is factual, and yet it reads so much like fiction - or rather, like film. Thus, a tantalizing tension sneaks up on him when Natalia first mentions Leone Ginzburg, the dark-haired young radical who worked at Einaudi, and whom the reader instantly knows she will marry, though she still seems to be a child at that point in the book.

But Natalia refuses to talk once about her own feelings, even when her children are born, when she and her husband live in confinement in a hill town during the war, or when Leone dies in a German prison in Rome in 1944. These are events which took place. She records them. They are part of the documentary she has set out to make. Her very discretion and reticence are moving, endowing her with dignity and winning our respect.

''Family Sayings'' was originally published in the United States in 1967, but , according to Simon Gavron of Carcanet Press, it ''sank without a trace.'' Like a low-budget experimental film, it may still be too offbeat, too unpretentious, too subtly intelligent, too special, to make a huge sensation on the English-speaking book market.

What it does do is draw us through the wringer of those uncomfortable, crucial decades in the company of some rather uncongenial yet admirable people. And it manages to make us care about them, to feel as if we were sitting around the dinner table with them, eating omelets and prepackaged soup.