| 摘要 |
PURPOSE: To effectively eliminate harmful noise resulting from image compression by applying inverse quantization to a signal obtained from converted and quantized frequency space data from input image information, conducting inverse frequency conversion and filtering the result so as to eliminate noise. CONSTITUTION: The image processing unit 1 uses a subtractor 2 to receive input image information consisting of blocks each comprising 8-pixel × 8-line and the result is given to an FDCT conversion section 3. The control section 3 converts the input image information into a signal denoting a frequency space through discrete cosine transformation and image data denoting 64 DCT coefficients (frequency coefficients) corresponding to number of pixels are quantized, and an inverse quantization section 5 produces a non-zero coefficient parameter. The quantization section 4 generates a quantization threshold level and provides an output to a filter section 8. An IDCT section 6 applies inverse DCT transformation to image data subject to inverse quantization and image information is outputted to a filter section 8 via an adder 7. The filter section 8 eliminates noise based on the non zero coefficient parameter. The image data are stored in a memory 9. A motion compression section NO synthesizes signals from the memory and best approximated frame signals and subtracts the result from the input frame signal. |
