Oscar winner Petro Vlahos, chief scientist of the Motion Picture Research Council and an innovator in visual effects who vastly improved bluescreen matting and made greenscreen possible on film through his Ultimatte techniques, died Monday. He was in his mid-90s.

In a tribute to Vlahos at AMPAS’ Sci Tech Awards last weekend, Academy governor Bill Taylor said, “Pete’s most important achievement made a whole genre of films possible: He invented composite photography as we know it today. Not just a few systems: the whole range, bluescreen, greenscreen, sodium vapor, photographic, Ultimatte real time analog and digital video and software embodiments. One guy did this: When you see Mary Poppins dancing with penguins, when you see Pi in a boat in the middle of the ocean, you are seeing Pete Vlahos’ genius at work.”

Vlahos’ honors from the Academy started with a Scientific and Technical Award in 1960 for a camera flicker indicating device. He earned an Oscar statuette in 1964 for the conception and perfection of techniques for color traveling matte composite cinematography and another in 1994 for the conception and development of the Ultimatte electronic bluescreen compositing process for motion pictures. He also received a Medal of Commendation in 1992 and the Gordon E. Sawyer Award, an Oscar statuette, in 1993.

Vlahos held more than 35 patents for a wide range of film industry innovations including camera crane motor controls, screen brightness meters, safe squib systems, cabling designs and junction boxes, projection screens and optical sound tracks. He also created analog and digital hardware and software versions of Ultimatte, the first high-quality electronic compositing system. (Vlahos founded the Ultimatte Corp. with his son Paul Vlahos in 1976.)

As his patents ran out, many competing digital bluescreen and greenscreen compositing systems were derived from Ultimatte. As a result, an Academy bio says, every greenscreen or bluescreen shot in a vast number of films (including every recent blockbuster fantasy pic) employs variants of Vlahos’ original techniques.

Vlahos’ version of the sodium system was used on dozens of Disney films, including “Mary Poppins” (1964), “The Love Bug” (1969) and “Bedknobs and Broomsticks” (1971); it was also borrowed by Alfred Hitchcock for “The Birds” and by Warren Beatty for “Dick Tracy.” The color difference system (the perfected bluescreen system), which he developed for 1959’s “Ben-Hur,” was used in hundreds of films, including the first “Star Wars” trilogy.

Vlahos long served on the awards committee for the Academy of Motion Picture Arts & Sciences’ Sci Tech Awards, creating the guidelines, now known as the Vlahos Criteria, for assessing achievements to be honored.