I thought i'd post what I know about deinterlacing algorithms to make sure I got this right in my head (please correct anything you think may be wrong) PAL 50 fields per second: Bob Bob takes each field (25th of a second), and scales it(stretches it vertically) to make a full frame by interpolation (this could be by simple line doubling or by using a filter such as bilinear/bicubic etc to smooth it). It then shows these frames one at a time 50 times a second. Advantages: * Smooth movement, scrolling messages are clear and easy to read with no jagged edges or combing. Disadvantages: * Still horizontal lines appear to "bob" up and down * Half vertical resolution, poor picture quality for film sourced images Weave - 2:2 pull down Weave takes each field and weaves it with the next field to produce a full frame. It then shows these frames for twice as long every 50th of a second, which results in 25 individual frames per second. Advantages * Highest vertical resolution for film sourced images * No deinterlacing artifacts at all Disadvantages * Video sourced images where the fields do not weave together properly will exhibit combing (horizontal lines when there is movement). Line Average Line average takes each field and weaves it with the next field, with video sourced images, the part of the picture where fields do not weave together properly it applies bob to the moving part of the frame only. Advantages * Still images are full vertical resolution * No bobbing lines with still images * No combing Disadvantages * Half vertical resolution for moving parts of the picture. * Jagged edges around moving objects (such as peoples mouths and horizontal scrolling text).