| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a method of compressing and expanding a digital signal at low power consumption in dynamic image processing. SOLUTION: In this digital signal compression method, two-dimensional data within a frame being an image signal are transformed into DCT coefficients at coordinates (X and y) by a one-dimensional discrete cosine transform unit 17 related to coordinate x, and are written in a random access memory 18. They are read out in the direction of axis y from a random access memory 19, are transformed into DCT coefficients at coordinates (X and Y) by a one-dimensional discrete cosine transform unit 20 related to the coordinate y, and are written in a random access memory 21, as data having coordinates (X, Y, and t). They are read out in the direction of time axis (t) from a random access memory 22, and are transformed into DCT coefficients at coordinates (X, Y, and T) by a one-dimensional discrete cosine transform unit 23 related to the coordinate (t), and they are outputted as a compressed image signal.</p> |
