| 摘要 |
<p>In order to edit commercial messages from an off-the-air video recording of a television signal, method and apparatus are disclosed for automatically operating a video tape recorder (VTR) (14), so that it alternates between a normal forward record mode, and a rewind or backscan mode in response to the detection of audio and video fade conditions in the television signal which occur at the beginning and end of each commercial message. A fade detection circuit (16) receives the television signal, while it is being recorded on the VTR, and develops a control signal response to each detected fade transition such that a single commercial interruption in the television program will be accompanied by a first and than a second fade transition control signal marking the beginning and end of the interruption. Two consecutive commercial messages are accompanied by a first, second, and then a final or third fade control signal. Cooperating with the fade detection circuit (16) is a reciprocating editing control (18) which receives the first fade control signals, memorizes the corresponding location on the tape, and then upon receiving the second fade control signal, stops the record mode of the VTR (14), reverses the tape to the memorized location of the first detected fade transition, and then restarts the recording operation at that tape location. Succeeding fade control signals cause a repeat of the foregoing reverse-forward sequence such that the last detected fade transition in a series, will position the tape for recording the resumption of the post-commercial program content of the television signal at approximately the same tape position where the recording of the precommercial program terminated, thereby resulting in a video tape recording of the program with commercial interruption deleted.</p> |
