What do terms like QCIF and QSIF mean?
These are acronyms denoting certain “standard” image formats as used with PC cameras in video conferencing. Typical PC camera image formats are • QSIF (Quarter SIF): 160 x 120 pixels (NTSC) or 192 X 144 pixels (PAL). • QCIF (Quarter CIF): 176 x 144 pixels, defined to run at 29.97 fps (frames per second). • SIF (Standard/Source Input Format): 320 x 240 pixels (NTSC) or 384 X 288 pixels (PAL). • CIF (Common Interface/Image Format): 352 x 288 pixels, defined to run at 29.97 fps. • 4CIF (four times CIF): 704 x 576 pixels, defined to run at 29.97 fps. • VGA (Video Graphic Adapter): 640 x 480 pixels. Quite often, the fps value specified with the CIF-derived formats is neglected, and only the respective resolutions are meant when referring to CIF, QCIF or 4CIF. Note that sometimes even very common video formats are not supported by a device. For instance, the Pinnacle Dazzle DVC 100 USB video capture device, sold as part of Dazzle DVD Recorder, does not support the 176 x 144 pixels format tha
