Patent ID: 7869085

Claim:
A rate conversion apparatus comprising: a first memory configured to store an input image signal temporarily; a second memory configured to store an image signal transferred from said first memory successively in the unit of line and reading out the image signal at a pixel period and a line period to obtain an output image signal; and a controller configured to control the write to and read-out of said first memory and said second memory, wherein said controller controls transferring of the image signal from said first memory to said second memory at a fixed period such that the output image signal has a different number of pixels than the input image signal, a period for said transfer being a length of time obtained according to an equation, t=mo/mi/fo×no wherein the period of said transfer is t, the pixel frequency of said output image signal is fo, the number of lines objective for conversion of said input image signal is mi, the number of lines of a single vertical effective period of said output image signal is mo, and the number of pixels per line of said output image signal is no.