| 摘要 |
PROBLEM TO BE SOLVED: To reduce the size and the power consumption of a device for recording and reproducing compressed signals based on copyright information. SOLUTION: An electronic watermark detector 4 is provided in a reproducing device 1 to detect copyright information. Based on the information, a controller 5 conducts controls such as prohibiting the outputting of data to a recording and reproducing device 6, In the device 6, a DSP 8 reads an instruction code for data compression from an instruction memory 9 based an the output of a connection detecting means 7 during a recording (a connection period) and conducts data compression. A ciphering device 10 performs a ciphering of the compressed data and stores the data into a storage device 11. During data reproducing, the means 7 reads an instruction code for data expansion from the memory 9 and transmits the code to the DSP 8 regardless of the presence or the absence of the device 1. Then, the DSP 8 conducts an expansion process of the data in the device 11 being decoded by the device 10. |
