Abstract: A single channel circuit and method for the automatic edit optimization of a recording medium which is operable with a recorder such as a video tape recorder or a disc recorder utilizes the difference between signal outputs from an automatic scan tracking playback head and a record, head to provide a difference signal indicative of the rf amplitude fluctuations caused by scene or data pattern variations of the data stored on the recording medium. A correction signal corresponding to the difference signal is stored, and used as a feedback signal to normalize the gain of a variable gain amplifier. The single channel is switched at a predetermined rate between circuitry coupled to the automatic scan tracking playback head and circuitry coupled to the record head in order to obtain rf amplitude samples from both heads to develop the correction signal. Thereby, the correction signal allows a precise edit optimize so that a subsequent edit operation such as an insert edit can be precisely performed.

Abstract: A scan tracking centering algorithm is not left at a nominal value, but is modified based on a tape timer's position into the field. That is, the scan tracking centering is adjusted forward (i.e., down) if the tape timer indicates the tape position is early in the field, and is adjusted back (i.e., up) if the indicated tape position is late in the field. Thus, the head deflection control decision which determines if the jumps, or doesn't jump, is made dependent upon tape position in the field, as well as on head elevation.

Abstract: Plural magnetic transducing heads are employed to record and reproduce video information that is stored in a segmented format. One head is in contact with the magnetic recording tape while the other head is out of contact with it. The position of the head which is in contact with the tape is controlled by a suitable ramp voltage generated in accordance with the ratio of actual tape speed to normal play speed, to maintain the head generally aligned with a track on the tape. The other head, which is out of contact with the tape, is also positioned in the same fashion. When a repositioning of the heads is required, a determination is made whether the track of information being reproduced by the head in contact with the tape relates to a particular segment of a field, for example the last field.

Abstract: A technique for recovering helical audio using the standard synchronous reference clock of the video tape recorder system to conventionally clock the transport and the video signal processor, including the video timebase corrector. A modified audio signal processor clock is generated which is varied commensurate with the desired rate of tape speed override, varying accordingly the flow of audio data through an audio timebase recorder. The speed of a helical scanner is varied in accordance with the rate of tape speed override, to lock the scanner angular position to the audio timebase corrector. In turn, a capstan servo adjusts the tape position in respsonse to the scanner angular position to lock the tape to the scanner. Meanwhile, the video signal processing proceeds conventionally by skipping or repeating fields or frames via a frame store to match the rate of tape speed override.

Abstract: To position a cue location on a video tape to a scanner so that the information stored at the cue location can read by a transducer. The video tape is transported so that when the cue location arrives at the scanner, the tape is moving at a selectable desired velocity. A synchronous cueing function is also provided for, in which the cue location is advanced at the rate of the desired velocity during to cueing operation to allow the positioning to be synchronized with other devices when the cue operation is completed.

Abstract: Apparatus for tensioning tape extending between two reels in a tape transport system having servos for controlling the velocity and position of the reels, includes position servo loop for maintaining the first reel in a fixed position. A velocity servo loop controls the other reel for taking up slack in the tape between the reels and applying a relative force on the tape once the slack has been taken up. The velocity servo is limited in the amount of current applied to the motor driving the take up reel by a signal provided by a tension servo connected to the position servo associated with the other reel. In particular, the tension servo responds to the amount of current applied by the position servo for applying a motor-current-limiting signal to the velocity servo system. When the position servo is applying minimal current to the fixed-position reel (when the tape is slack), a relatively large amount of current is allowed to go to the take up reel.

Abstract: An audio/video editing system presents different menus of editing functions on a display screen and changes the menus as well as performing different editing functions in response to the touching of selected areas of the display screen by an operator. An arrangement of light emitting diodes and photodetectors provides a network of beams across the face of the display screen. Selected beams are interrupted when the operator points his finger at particular characters being displayed on the screen. The display menus and editing functions are controlled by an edit controller which includes a central processing unit having a memory loaded with data from a computer file system, a character generator for providing the various menus on the display screen and a plurality of intelligent line controllers coupled to a plurality of source tape recorders, a record tape recorder and a switcher capable of coupling a different one of the source recorders to the record recorder.