RESOLUTION CONVERSION DEVICE AND METHOD

摘要

PROBLEM TO BE SOLVED: To make the boundary of a DCT processing not to be accentuated. SOLUTION: An A/D converter 12 digitizes a picture signal from an input terminal 10. Its output is supplied to the (a) contact of a switch 16 through a delay unit 14, and is supplied directly to the b contact of the switch 16. The DCT processor 20 performs the DCT of image data from the switch 16. The delay time of the delay unit 14 is set for time equivalent to the half of a DCT processing unit by the DCT processor 20. A control circuit 18 switches the switch 16 for each frame. An interpolator 22 adds '0' value as a 9th high frequency component to 8 DCT coefficients, and outputs them to a reverse DCT processor 24 a 9 DCT coefficients. The reverse DCT processor 24 performs a reverse DCT processing by using 9 coefficients as a unit, and outputs the 9 pixel data to the delay unit 26 and the b contact of a switch 28. The output of the delay unit 26 is applied to the (a) contact of the switch 28. The control circuit 18 switches the switch 28 as well as the switch 16 for every frame.