Burnt-in timecode (often abbreviated to BITC by analogy to

VITC Vertical Interval Timecode (VITC, pronounced "vitsee") is a form of SMPTE timecode encoded on one scan line in a video signal. These lines are typically inserted into the vertical blanking interval of the video signal. With one exception, VITC ...

) is a

human-readable A human-readable medium or human-readable format is any encoding of data or information that can be naturally read by humans. In computing, ''human-readable'' data is often encoded as ASCII or Unicode text, rather than as binary data. In most c ...

on-screen version of the

timecode A timecode (alternatively, time code) is a sequence of numeric codes generated at regular intervals by a timing synchronization system. Timecode is used in video production, show control and other applications which require temporal coordinatio ...

information for a piece of material superimposed on a video image. BITC is sometimes used in conjunction with "real" machine-readable timecode, but more often used in copies of original material on to a non-broadcast format such as VHS, so that the VHS copies can be traced back to their master tape and the original time codes easily located. Many professional

VTR A video tape recorder (VTR) is a tape recorder designed to record and playback video and audio material from magnetic tape. The early VTRs were open-reel devices that record on individual reels of 2-inch-wide (5.08 cm) tape. They were us ...

s can "burn" (overlay) the tape timecode onto one of their outputs. This output (which usually also displays the setup menu or

on-screen display An on-screen display (OSD) is an image superimposed on a screen picture, commonly used by modern television sets, VCRs, and DVD players to display information such as volume, channel, and time. History In the past, most adjustments on TV sets ...

) is known as the ''super out'' or ''monitor out''. The ''character'' switch or menu item turns this behaviour on or off. The ''character'' function is also used to display the timecode on the preview monitors in

linear editing Linear video editing is a video editing post-production process of selecting, arranging and modifying images and sound in a predetermined, ordered sequence. Regardless of whether it was captured by a video camera, tapeless camcorder, or recorded in ...

suites. Videotapes that are recorded with timecode numbers overlaid on the video are referred to as ''window dubs'', named after the "window" that displays the burnt-in timecode on-screen. When editing was done using magnetic tapes that were subject to damage from excessive wear, it was common to use a window dub as a working copy for the majority of the editing process. Editing decisions would be made using a window dub, and no specialized equipment was needed to write down an

edit decision list An edit decision list or EDL is used in the post-production process of film editing and video editing. The list contains an ordered list of reel and timecode data representing where each video clip can be obtained in order to conform the final cu ...

which would then be replicated from the high-quality masters. Timecode can also be superimposed on video using a dedicated overlay device, often called a "window dub inserter". This inputs a video signal and its separate timecode audio signal, reads the timecode, superimposes the timecode display over the video, and outputs the combined display (usually via composite), all in real time. Stand-alone timecode generator / readers often have the window dub function built-in. Some consumer cameras, in particular DV cameras, can "burn" (overlay) the tape timecode onto the composite output. This output typically is semi-transparent and may include other tape information. It is usually activated by turning on the 'display' info in one of the camera's sub-menus. While not as 'professional' as an overlay as created by a professional

VCR A videocassette recorder (VCR) or video recorder is an electromechanical device that records analog audio and analog video from broadcast television or other source on a removable, magnetic tape videocassette, and can play back the recording. ...

s, it is a cheap alternative that is just as accurate. Timecode is stored in the metadata areas of captured DV AVI files, and some software is able to "burn" (overlay) this into the video frames. For example, DVMP ProDVMP Pro
- Software for burning in timecode and other items of metadata for DV AVI files. is able to "burn" timecode or other items of DV metadata (such as date and time, iris, shutter speed, gain, white balance mode, etc.) into DV AVI files. OCR techniques can be used to read BITC in situations where other forms of timecode are not available.

References

{{DEFAULTSORT:Burnt-In Timecode Timecodes Film and video technology

See also

References