COMPRESSION RECORDER

摘要

PROBLEM TO BE SOLVED: To generate a reproduced image with excellent quality without folding distortion or ringing by allowing each of a plurality of pixel blocks subjected to orthogonal transformation to include a plurality of transformation coefficients. SOLUTION: A compressed image generating section 100 uses a filter to apply band limitation to an input image signal so as to generate a compressed image as a result of thinning to 1/2 longitudinally and 1/2 laterally and the compressed image is given to an orthogonal transformation section 101. The transformation section 101 processes the compressed image into a block of 4×4 pixels and applies the DC transformation to the image in the unit of blocks and provides an output of a DCT coefficient to a zero coefficient addition section 102. The addition section 102 adds 48-sets of 0 coefficients to a block consisting of 16-sets of DCT coefficients to re-configure the block into a DCT block consisting of 64-sets of DCT coefficients. A compression section 103 applies quantization and variable length coding to the DCT block to generate compression data and provides an output of the result. DCT is applied to the 4×4 pixels in this way to obtain a reproduced image with excellent quality with a smaller circuit scale than that of the case with 8×8 pixels.