An image display device comprising: display means capable of stereoscopically displaying a stereoscopic image generated from more than one images taken from different points of view; input means for receiving an instruction to control a stereoscopic effect of the stereoscopic image while the stereoscopic image is stereoscopically displayed by the display means; three-dimensional processing means for applying three-dimensional processing for stereoscopic display to the more than one images to generate the stereoscopic image, the three-dimensional processing being applied to achieve a stereoscopic effect according to the instruction; and recording control means for recording, in a recording unit, control values of the stereoscopic effect according to the instruction, the control values being associated with the more than one images, wherein, if there are the control values of the stereoscopic effect recorded in the recording unit, the recording control means records, in the recording unit, difference values between the control values of the stereoscopic effect according to the instruction and the recorded control values of the stereoscopic effect; wherein, according to the instruction to control the stereoscopic effect, the display means trims an area having an aspect ratio identical to that of each of the more than one images from an overlapping range between the more than one images in the stereoscopic image, and displays the stereoscopic image with adding a frame indicating the trimmed area around the stereoscopic image with respect to the trimmed area; and wherein, where the control values of the stereoscopic effect comprise a parallax level between the more than one images, the display means changes a colour of the frame stepwise according to the magnitude of the parallax level as the parallax level increases to notify a user that the parallax level is becoming too large for stereoscopic vision. display means capable of stereoscopically displaying a stereoscopic image generated from more than one images taken from different points of view; input means for receiving an instruction to control a stereoscopic effect of the stereoscopic image while the stereoscopic image is stereoscopically displayed by the display means; three-dimensional processing means for applying three-dimensional processing for stereoscopic display to the more than one images to generate the stereoscopic image, the three-dimensional processing being applied to achieve a stereoscopic effect according to the instruction; and recording control means for recording, in a recording unit, control values of the stereoscopic effect according to the instruction, the control values being associated with the more than one images, wherein, if there are the control values of the stereoscopic effect recorded in the recording unit, the recording control means records, in the recording unit, difference values between the control values of the stereoscopic effect according to the instruction and the recorded control values of the stereoscopic effect; wherein, according to the instruction to control the stereoscopic effect, the display means trims an area having an aspect ratio identical to that of each of the more than one images from an overlapping range between the more than one images in the stereoscopic image, and displays the stereoscopic image with adding a frame indicating the trimmed area around the stereoscopic image with respect to the trimmed area; and wherein, where the control values of the stereoscopic effect comprise a parallax level between the more than one images, the display means changes a colour of the frame stepwise according to the magnitude of the parallax level as the parallax level increases to notify a user that the parallax level is becoming too large for stereoscopic vision.