A semiconductor device capable of deleting data already recorded on a recording medium when information indicative of prohibition of copying is detected from picture signal. Input portion receives an input picture signal, and copy protection information detecting portion detects copy protection information included in the picture signal input from the input portion. Compressing portion compresses the picture signal, and compressed data output portion outputs compressed data obtained by the compressing portion. Specification information output portion generates and outputs specification information specifying a position of the compressed data where the information indicative of prohibition of copying was detected first by the copy protection information detecting portion. A device for recording the compressed data can specify the head of unnecessary compressed information by looking up the specification information, whereby the unnecessary information can be deleted from the recording medium.