| 摘要 |
Unique digital codes are encoded on a video signal, the codes are retrieved at receivers and precise information concerning the time of occurrence, length, nature and quality of a monitored broadcast at a frame by frame level, is generated. The codes are inserted on scan lines of the video, and vary either on a field-to-field or fame-to-frame basis. The code has a repeating first part having a unique program material identifier indicating the time, date and place of encoding, and has a second portion that varies in a predetermined non-repeating sequence which varies along the entire length of the tape, thereby uniquely identifying each frame of the video program material. Also encoded upon successive frames is a cyclic counter code with a count corresponding to the sequence of the identifier data on successive frames. When the video signal is processed by a receiver, the first portion identifier data from the various frames is mapped into selected memory locations in accordance with the count of the frame as determined by the second portion. Odd and even fields are encoded with complementary bit sequences to assist in processing the encoded data. Whenever the frame sequence is interrupted a data packet is generated representative of the condition encountered. The data packets are accumulated in log files in a memory in the receiver. The log files are transmitted to a data center, as is a copy of the encoded tape. Reports concerning the broadcast are generated.
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