This is also known as FCIF (Full CIF). This is a format used to standardise the horizontal and vertical resolutions in pixels of YCbCr sequence in video signals, commonly used in video teleconferencing systems. It was first proposed in the H.261 standard.
The CIF image sizes were specifically chosen to be multiples of macro blocks (i.e. 16x16 pixels) because the way the desecrate con sine transform based video compression and decompression is handled. So, by example, a CIF image size (352x288) consists of 22x18 macro blocks.
SIF (Source Input Format) is practically identical to CIF, but taken from MPEG-1 rather than ITU Standards. SIF on 525 line(NTSC) is 352x240, and on 625 line ("PAL") is 352x288 which is identical to the CIF. SIF and 4SIF are commonly used in the video conferencing systems.
DCIF means Double CIF and is introduced as a compromised solution between CIF and 4CIF that is more balanced (in terms of horizontal and vertical resolution) and suited to common CCTV equipment
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