A method of boosting a displayed image of a liquid crystal display by local boosting, the liquid crystal display including a backlight assembly having a plurality of dimming blocks that are independently driven by respective local dimming signals, wherein boosting comprises increasing the luminance of a portion area of the dimming blocks, the method comprising: analyzing image data supplied from an external device to determine whether or not the image data satisfies boosting conditions set in order to increase a luminance in the portion area of the dimming blocks, hereinafter referred to as boosting area, in comparison with a peripheral area of the dimming blocks adjacent to the boosting area; generating the plurality of local dimming signals for individually driving the dimming blocks in response to the image data; increasing the luminance value in the local dimming signals corresponding to the boosting area when the image data satisfies the boosting conditions; converting the image data of a peripheral area into conversion image data so that the luminance of the peripheral area adjacent to the boosting area is decreased, wherein the step of converting comprises: gamma converting image data corresponding to an entire area except for the peripheral area by using a reference gamma curve (R-CV) corresponding to a first gamma value, and gamma converting image data of the peripheral area by using a conversion gamma curve (C-CV) corresponding to a second gamma value for displaying a darker luminance image than an image corresponding to the reference gamma curve (R-CV). analyzing image data supplied from an external device to determine whether or not the image data satisfies boosting conditions set in order to increase a luminance in the portion area of the dimming blocks, hereinafter referred to as boosting area, in comparison with a peripheral area of the dimming blocks adjacent to the boosting area; generating the plurality of local dimming signals for individually driving the dimming blocks in response to the image data; increasing the luminance value in the local dimming signals corresponding to the boosting area when the image data satisfies the boosting conditions; converting the image data of a peripheral area into conversion image data so that the luminance of the peripheral area adjacent to the boosting area is decreased, wherein the step of converting comprises: gamma converting image data corresponding to an entire area except for the peripheral area by using a reference gamma curve (R-CV) corresponding to a first gamma value, and gamma converting image data of the peripheral area by using a conversion gamma curve (C-CV) corresponding to a second gamma value for displaying a darker luminance image than an image corresponding to the reference gamma curve (R-CV). gamma converting image data corresponding to an entire area except for the peripheral area by using a reference gamma curve (R-CV) corresponding to a first gamma value, and gamma converting image data of the peripheral area by using a conversion gamma curve (C-CV) corresponding to a second gamma value for displaying a darker luminance image than an image corresponding to the reference gamma curve (R-CV).