ASPECT RATIO IN FILM, TELEVISION AND COMPUTERS

Standard VGA color palette

The Academy ratio of 1.375:1 (abbreviated as 1.37:1) is an aspect ratio of a frame of 35 mm film when used with 4-perf pulldown. It was standardized by the Academy of Motion Picture Arts and Sciences as the standard film aspect ratio in 1932, although similar-sized ratios were used as early as 1928.

The first standards set for the new sound-on-film motion pictures were accepted in November 1929, when all major US studios agreed to compose for the Society of Motion Picture Engineers’ (SMPE) designated size of 0.800 in × 0.600 in (20.3 mm × 15.2 mm) returning to the aspect ratio of 4:3. All studio films shot in 35 mm from 1932 to 1952 were shot in the Academy ratio.

Following the widescreen “revolution” of 1953, 4:3 quickly became an obsolete production format. Within several months, all major studios started matting their non-anamorphic films in the projector to wider ratios such as 1.6, 1.75, and 1.85, the last of which is still considered a standard ratio along with highly anamorphic (2.39). One driver of anamorphic aspect ratios was theater size.

In 1964 there was a monochrome plasma display available. The PLATO computer used the display which offers 512×512 resolution which sold for $2500.

The IBM 3270 was 80×24 character but it is incapable of bitmapped graphics. There were also 3 indicators including input inhibited, The IBM PC offered the same 80×24 so it was a familiar platform. The Hercules Graphics Card ($499, 1982) offered a better solution with 720×348 graphics mode. Clone cards surfaced quickly.

The IBM VGA introduced better color and the 640×480 4:3 aspect ratio is still rock solid. SVGA bumped the resolution to 800×600 which was very popular from 1987 to 1990. The IBM XGA was heavily interlaced but almost instantly clones offered 1024×768 non interlaced, Well into the 2000s, even after the VESA standard for graphics cards became commonplace, the “VGA” graphics mode remained a compatibility option for PC operating systems.

Advanced Television Systems Committee (ATSC) HDTV replaced much of the US televisions stations on June 12, 2009. In Canada the changeover was on  August 31, 2011. 1280×720 and 1920×1080 are now new 16:9 aspect ratio which fundamentally changed filming, video recording and more. Dolby AC-3 is the standard for audio for television. The maximum bit rate value in the sequence header of the MPEG-2 video stream is 19.4 Mbit/s for broadcast television, and 38.8 Mbit/s for the “high data rate” mode (e.g., cable television). The actual MPEG-2 video bit rate will be lower, since the MPEG-2 video stream must fit inside a transport stream.

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