Characteristics of a digital video signal are detected by first characteristics detection means, and characteristics of a digital audio signal are detected by second characteristics detection means. The outputs from the first and second characteristics detection means are combined by synthesizing means, and allocated data quantities for compression coding of the digital video signal and the digital audio signal are controlled on the basis of the output from this synthesizing means. In this way, degradation of the video signal and the audio signal associated with the video signal during reproduction is eliminated, and compression encoding can be made more efficiently.