Source Input Format (SIF) defined in

MPEG-1 MPEG-1 is a standard for lossy compression of video and audio. It is designed to compress VHS-quality raw digital video and CD audio down to about 1.5 Mbit/s (26:1 and 6:1 compression ratios respectively) without excessive quality loss, making ...

, is a video format that was developed to allow the storage and transmission of digital video. * 625/50 SIF format (

PAL Phase Alternating Line (PAL) is a colour encoding system for analogue television. It was one of three major analogue colour television standards, the others being NTSC and SECAM. In most countries it was broadcast at 625 lines, 50 fields (25 ...

SECAM SECAM, also written SÉCAM (, ''Séquentiel de couleur à mémoire'', French for ''color sequential with memory''), is an analog color television system that was used in France, some parts of Europe and Africa, and Russia. It was one of th ...

) has a resolution of (360 or) 352 x 288 active pixels and a

refresh rate The refresh rate (or "vertical refresh rate", "vertical scan rate", terminology originating with the cathode ray tubes) is the number of times per second that a raster-based display device displays a new image. This is independent from frame rate ...

of 25 frames per second. * 525/59.94 SIF Format (

NTSC The first American standard for analog television broadcast was developed by National Television System Committee (NTSC)National Television System Committee (1951–1953), Report and Reports of Panel No. 11, 11-A, 12–19, with Some supplement ...

) has a resolution of (360 or) 352 x 240 active pixels and a refresh rate of 29.97 frames per second. When compared to the

CCIR 601 ITU-R Recommendation BT.601, more commonly known by the abbreviations Rec. 601 or BT.601 (or its former name CCIR 601) is a standard originally issued in 1982 by the Comité consultatif international pour la radio, CCIR (an organization, ...

specifications, which defines the appropriate parameters for digital encoding of TV signals, SIF can be seen as being reduced by half in all of height, width, frame-rate, and chrominance. SIF video is known as a

constrained parameters bitstream Constraint may refer to: * Constraint (computer-aided design), a demarcation of geometrical characteristics between two or more entities or solid modeling bodies * Constraint (mathematics), a condition of an optimization problem that the solution m ...

.What are Constrained Parameters Bitstreams ?
The computer industry has defined square-pixel SIF to be 320 x 240 (

QVGA The graphics display resolution is the width and height dimension of an electronic visual display device, measured in pixels. This information is used for electronic devices such as a computer monitor. Certain combinations of width and height ar ...

) or 384 x 288 active pixels with a refresh rate of whatever the computer is capable of supporting.

References

{{reflist Graphics standards MPEG

See also

References