http://terms.inmatrix.com/
Quote:
Interlacing:
Your T.V. screen does not work like a Computer Monitor. A computer monitor display is a square, it has fixed points at exactly the same distance from eachother both vertically and horizontally. However, your T.V. screen is interlaced, if you look closely at your T.V. screen, you will see that it is in fact a lot of small vertical Red, Green and Blue lines placed closely next to eachother. Not only that, these lines are slightly offset to eachother on each screen row. A T.V. also updates the image differently compared to a Computer Monitor. The final result is, when trying to play a T.V. image on a Computer Monitor, you will get visible horizontal streaking when the camera pans. To deal with this, DVD software decoders have come up with some DeInterlacing code (see below).
DeInterlacing - Weave:
Weave is the default mode that should be used when viewing progressive DVD data (Movies for example). Using this mode you will see horizontal streaking for non-movie data (NTSC/PAL content such as movie trailers). If you plan on viewing DVD movies, you must set your decoding software to weave mode. Weave is the default DeInterlacing mode all decoding software use for Movie playback (unless set to some sort of detection mode).
DeInterlacing - BOB:
T.V. playback works a bit differently compared to a computer monitor. It has two fields, each playing in an interlaced form at either 30 or 25fps (NTSC/PAL). When NTSC/PAL content is played on a computer monitor using the standard Weave DeInterlacing mode, you get a lot of horizontal streaking when the camera pans or objects move quickly within a scene. To combat this, you can use the BOB DeInterlacing mode. What BOB does is play the content at twice it's frame rate and each frame is displayed in only one of the fields. This makes the image appear to BOB up and down a bit, especially when text is displayed, but doing so eliminates the streaking. Using the BOB mode is only useful for NTSC/PAL content such as Movie Trailers. On Progressively encoded Movie content BOB will cause the image to look slightly blurred.