F

field

In broadcast television, one of two sets of alternating lines in an interlaced video frame. In one field, the odd-numbered lines of video are drawn; in the other, the even-numbered lines are drawn. When interlaced, the two fields combine to form a single frame of on-screen video.

File Transfer Protocol

(FTP) A protocol that supports file transfers to and from remote systems on a network using Transmission Control Protocol/Internet Protocol (TCP/IP), such as the Internet. FTP supports several commands that allow bidirectional transfer of binary and ASCII files between systems. See also Hypertext Transport Protocol (HTTP).

filter

See announcement filter, DirectShow filter, KSProxy filter.

filter graph

A connected set of DirectShow filters that processes media data by controlling KSProxy filters.

filter graph manager

An object that controls how a filter graph is assembled and how data is moved through it. Applications can use the filter graph manager implicitly, allowing it to construct an appropriate filter graph for a specified media format. Applications can also access the filter graph manager explicitly — for example, to add a proprietary filter to a filter graph.

forward error correction

A system of error correction that incorporates redundancy into data so transmission errors can, in many cases, be corrected without requiring retransmission.

frame

In broadcast television, a single screen-sized image that can be displayed in sequence with other slightly different images to animate drawings. For NTSC video, a video frame consists of two interlaced fields of 525 lines; NTSC video runs at 30 frames per second. For PAL or SECAM video, a video frame consists of two interlaced fields of 625 lines; PAL and SECAM video runs at 25 frames per second. In comparison, film runs at 24 frames per second.

FTP

See File Transfer Protocol.