| 摘要 |
In a digital video tape recorder which employs discrete cosine transformation and variable length coding for compressing the data to be recorded, the necessity of an additional signal line for transmission of information incidental to the principal data is eliminated, and a processing margin is obtained in track units upon variable speed reproduction and the like. The digital video tape recorder samples an NTSC signal at a ratio of 4:1:1 or 4:2:0, transforms the sample data for each block of 8x8 data by DCT, encodes the transformed data into variable length codes so that 30 DCT blocks constitute a buffering unit having a fixed length to compress the data, and segmentally records the video signal obtained by the data compression divisionally in 10 tracks for each frame. In the digital video tape recorder, the frequency of a signal processing clock signal used for data compression is selected to be equal to 192/143 times the frequency of 13.5 MHz used for sampling the original analog component video signal when converting the same to digital form. A first blanking area for transmission of the incidental information is provided for each DCT block, and a second blanking area is provided for each track for obtaining the desired processing margin in track units upon variable speed reproduction and the like.
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