Patent ID: 8614719
Filing Date: 2013-12-24
Classification: H04N

Abstract:
1. A device for gamma compensation the device comprises: an input interface adapted to receive a non-gamma compensated input value and an output interface adapted to output a gamma compensated output value; a selection circuit comprising a low-brightness slope providing circuit, a high-brightness slope providing circuit, a low-brightness offset providing circuit and a high-brightness offset providing circuit, wherein the selection circuit is coupled to a memory unit, to a multiplier and to an adder, wherein the selection circuit is adapted to select, in response to the input value, a selected approximating interval out of a group of low-brightness approximating intervals and out of a group of high-brightness approximating intervals; wherein the memory unit is adapted to store information representative of the group of low-brightness approximating intervals and of the group of high-brightness approximating intervals; wherein at least one low-brightness approximating interval is smaller than at least one high-brightness approximating interval and wherein at least one low-brightness approximating interval is smaller than at least one other low-brightness; wherein a low-brightness approximating interval is characterized by a low-brightness approximating interval slope and by a low-brightness approximating interval offset representative of an imaginary intersection point between an output value axis and an imaginary line that extends from the low-brightness approximating interval towards the output value axis while having the low-brightness approximating interval slope; wherein a high-brightness approximating interval is characterized by a high-brightness approximating interval slope and by a high-brightness approximating interval offset representative of a start point of the high-brightness approximating interval; wherein the multiplier further coupled to the input interface and to the adder and is adapted to multiply a portion of the input value by a selected approximating interval slope to provide an intermediate result; wherein the adder is further coupled to the output interface and is adapted to add the intermediate result to a selected approximating interval offset to provide the gamma compensated output value.