Patent ID: 9389766
Filing Date: 2016-07-12
CPC Classification: G06F,G06T

Claim Text:
1. An image display device including a display unit configured to display an image in an image display area on a display screen and an input unit configured to receive an instruction input indicating a position on the display screen, comprising: at least one processor operable to read and operate according to instructions within a computer program; and at least one memory operable to store at least portions of said computer program for access by said processor; wherein said program includes algorithms to cause said processor to implement: an acquisition unit configured to acquire position information indicating a position of an instruction input received by the input unit; a region recognition unit configured to specify an enclosed region in the image display area enclosed by a trajectory indicated by a set of position information received by the acquisition unit based on sequential instruction inputs through the input unit and recognize the enclosed region as a selected region; a direction specifying unit configured to specify a direction of the trajectory enclosing the enclosed region based on the trajectory of the position information received by the acquisition unit; a determination unit configured to determine a zoom-in ratio of an image displayed in the image display area when the direction specified by the direction specifying unit is a first direction, and determine a zoom-out ratio of an image displayed in the image display area when the direction specified by the direction specifying unit is a second direction opposite to the first direction, based on a range of the image display area and a range of the selected region recognized by the region recognition unit; and a display control unit configured to cause a zoomed-in image obtained by zooming in the image displayed in the image display area with the zoom-in ratio determined by the determination unit to be displayed in the image display area with a center of the zoomed-in image and a center of the image display area coinciding with each other when the direction specified by the direction specifying unit is the first direction, and causes a zoomed-out image obtained by zooming out an image at least partly including the image displayed in the image display area with the zoom-out ratio determined by the determination unit to be displayed in the image display area with a center of the zoomed-out image and a center of the image display area coinciding with each other when the direction specified by the direction specifying unit is the second direction, wherein when position information based on sequential instruction inputs following the sequential instruction inputs related to specifying the enclosed region is additionally acquired by the acquisition unit after specifying the enclosed region by the trajectory of the position information, the region recognition unit acquires a trajectory of the position information received after specifying the enclosed region, the determination unit adjusts the zoom-in ratio or the zoom-out ratio of the image displayed in the image display area based on a position and an amount of displacement of the trajectory of the position information received after specifying the enclosed region acquired by the region recognition unit, the amount of displacement being measured from a point at which the enclosed region is specified, the point being included in the trajectory, and a degree of the adjustment of the zoom-in ratio or the zoom-out ratio varies according to the amount of displacement of the trajectory of the position information received after specifying the enclosed region acquired by the region recognition unit, when the trajectory of the position information received after specifying the enclosed region extends inside the enclosed region in the same direction in which the enclosed region is specified, the determination unit adjusts the zoom-in ratio or the zoom-out ratio of the image displayed in the image display area by making a change being one of an increase and a decrease to the ratio, the change being based on a position and a length of the trajectory extended inside the enclosed region, and when the trajectory of the position information received after specifying the enclosed region extends outside the enclosed region in the same direction in which the enclosed region is specified, the determination unit adjusts the zoom-in ratio or the zoom-out ratio of the image displayed in the image display area by making a change being another one of an increase and a decrease to the ratio, the change being based on a position and a length of the trajectory extended outside the enclosed region.