Patent ID: 7765413
Filing Date: 2010-07-27
Classification: H04N

Abstract:
1. An image processing device including a main control unit and a sub-control unit, the main control unit controlling each of an image input unit, an image processing unit, and an image output unit, the sub-control unit controlling power supply to the main control unit to change a mode of the image processing device to a power saving mode and to cause the mode of the image processing device to return from the power saving mode, and the sub-control unit controlling response and transmission of a network interface and a USB device provided in the image processing device for inputting or outputting of image data, the image processing device comprising: a state holding unit holding a state of a USB device driver provided in the main control unit; a state transition unit changing a state of the USB device driver; and a state acquiring unit acquiring a state of the USB device, wherein the state holding unit holds a state, referred to as a held state, of the USB device driver before the mode of the image processing device is changed to the power saving mode, and when the state of the USB device acquired by the state acquiring unit after the mode of the image processing device returns from the power saving mode, referred to as an acquired state, differs from the held state of the USB device driver held by the state holding unit, the state transition unit determines an estimated state-transition sequence for changing a state of the USB device driver, based on a result of comparison of the held state of the USB device driver and the acquired state of the USB device, and changes the state of the USB device driver according to the estimated state-transition sequence.