1. An image processing system comprising: an image pickup apparatus for picking up an image of a subject; and an image reproducing apparatus for reproducing the image picked up by said image pickup apparatus; wherein said image pickup apparatus includes an image pickup unit for obtaining an image by image pickup, an image pickup rate controlling unit for controlling an image pickup rate of said image pickup unit, a line reducing unit for removing a plurality of lines from said image obtained by the image pickup to generate a reduced image, an image storing unit for storing the reduced image on a storage medium, and an evaluation unit for determining a compression processing volume for compressing data of an image sequence by an encoder based on a product between a number of lines that remain in the reduced image and the image pickup rate, and said image reproducing apparatus includes an image reading unit for reading the image stored on said storage medium, an up-converter for up-converting the read said image, and a reproduction displaying unit for displaying said up-converted image, wherein in a case where the evaluation unit determines that the compression processing volume does not exceed a predetermined threshold, the line reducing unit is instructed not to remove the plurality of lines from the image, and in a case where the evaluation unit determines that the compression processing volume exceeds the predetermined threshold, the line reducing unit is instructed to remove at least some of the plurality of lines from the image.