According to theater buff Damien Farley at CinemaTreasures.org the Canton:
Opened as a home to both Yiddish vaudeville and motion pictures in 1911, the Florence Theatre, the exact address of which was 75-85 East Broadway, ended its existence as the Sun Sing in 1993.Here's an image from the theater's later days. I love the way it's nestled under the bridge.
By 1942, the theatre had been rechristened the New Canton Theatre and featured performances of Chinese opera and variety acts. In 1950, the facility was again re-dubbed, this time as the Sun Sing Theatre, and took to exhibiting Chinese language films, sometimes with English subtitles.
In 1960, the theatre was scheduled for demolition when faced with the addition of an upper deck to the Manhattan Bridge far above. However, city engineers were able to save the theatre and the adjoining retail space, through the use of innovative bridge supports which only caused the theatre’s seat count to be reduced, this time to 676.
In 1972, the theatre began to feature a mixed program of film and stage performances. It finally closed in 1993.
I can't find a rundown of what might have been playing on that particular evening in 1948, but here's a Chinese Opera mask, just cause it's cool.