measured in decibels. (0 dB, 6 dB, 18 dB, etc.)
Webcam
Progressive Scan
Some consumer camcorders, especially expensive ones, offer progressive scan options for the capturing of video. There are two different types of scanning: progressive and interlaced. Video is captured in fields of resolution. It is also captured at a certain frame rate (i.e. 30 frames-per-second, etc.). With interlaced scanning, there are two fields of data recorded within each frame. Each field consists of alternating lines of resolution. Once the two fields of alternating lines of resolution are recorded, a frame is said to be created, consisting of two interlocking frames of resolution. The fields of the resulting frame have been recorded in an alternating sequence. Therefore, in playback, one cannot stop and view a single frame and see a clear picture. Rather, when viewing frames