METHOD AND APPARATUS FOR ROTATION OF RECTANGULAR IMAGE BY USING MATRIX TRANSFORMATION

摘要

PURPOSE: To realize a device at a low cost and to reduce a delay time with rotation successively storing picture data by the form of a row and a column to obtain an outputted rotated by specific-fold through the use of a second address sequence. CONSTITUTION: Data corresponding to a picture line is successively received by a collecting and printing managing part 16 and stored in a rotation picture buffer memory 30. Next a rotation control part 32 starts the reading of data stored in the memory 30. Data read out from the memory 30 is sent to a main picture memory 18 through a path 21. Then the output of an MC counter 26 is compared with the value of a line register 22, and the value of an ML counter 24 is compared with the value of a pixel register 20. When the values of the two counters coincide with the output values of the registers, the picture is perfectly read out and sent to the memory 18 in a state that is rotated by 90 deg..