DEVICE AND METHOD FOR RECOGNIZING MARK IN DIGITAL VIDEO AND AUDIO DATA

摘要

PROBLEM TO BE SOLVED: To remove the effect to be given on the quality of a video or audio by padding information in a value of which error is not changed even when the value is approximated to any approximation value level by the use of quantization. SOLUTION: A mark recognizing device 1 is constituted of a distributed information writer 2 and a distributed information reader 3. The wrier 2 applies a mark, the reader 3 recognizes the mark and the device 1 attains its purpose by the cooperation of the writer 2 and the reader 3. When a difference between quantization errors is small at the time of quantizing a value to be quantized to any of two approximate value levels before and after the value to be quantized in the case of executing quantization for the A/D conversion of a video and audio or image compression, the value is selectively approximated to the approximate value level having a small quantization error or the approximate value level having a large quantization error. Consequently fixed information is padded in digital video data or digital audio data.