Image signal processing apparatus and a control method thereof, and an image pickup apparatus and a control method thereof

An image pickup apparatus comprising:

• a first resizing portion configured to reduce size of image data output by an image pickup element;
• a memory configured to store the image data reduced by the first resizing portion;
• a first signal processor configured to receive the image data from the memory and to perform a first signal processing to the image data received from the memory;
• an external output portion configured to output the image data to which the first signal processor performs the first signal processing;
• a second resizing portion configured to receive the image data reduced by the first resizing portion and to reduce the size of the image data reduced by the first resizing portion;
• a second signal processor configured to perform second signal processing to the image data reduced by the second resizing portion;
• and
• a display configured to display an image according to the image data to which the second signal processor performs the second signal processing,
• wherein the image data received by the second resizing portion has not been stored in the memory.