External storage device for image pickup apparatus, control method therefor, image pickup apparatus and control method therefor

A control method of an image pickup apparatus including an image storage medium capable of storing a plurality of captured images and image display means for displaying at least the plurality of captured images, said control method comprising:

• wire-communicating or wireless-communicating with an external storage device for backing up image information to be stored in the image storage medium;
• transferring predetermined image information from the image storage medium to the external storage device in said communication step;
• and
• receiving image information, which was transferred to the external storage device and converted therein into image information of less data amount, in said communication step and storing the received image information onto the image storage medium.

An image pickup apparatus including an image storage medium capable of storing a plurality of captured images and an image display device that displays at least the plurality of captured images, the image pickup apparatus comprising:

• a communication unit configured to be capable of wire-communicating or wireless-communicating with an external storage device for backing up image information to be stored in the image storage medium;
• a transfer processing unit configured to transfer predetermined image information from the image storage medium to the external storage device via said communication unit;
• and
• a control unit configured to receive image information, which was transferred to the external storage device and converted therein into image information of less data amount, via said communication unit and storing the received image information onto the image storage medium.