Patent ID: 9407910
Filing Date: 2016-08-02
CPC Classification: H04N

Claim Text:
1. A method, comprising accessing a set of N input values stored in a memory; and computing a set of N Discrete Cosine Transform (DCT) coefficients, including a DC coefficient, from the N input values by applying an ordered set of operations, the ordered set of operations comprising lifted butterfly operations; wherein the lifted butterfly operations results in, for any given input value pair comprising a first input value and a second input value, an output value pair comprising the average of the first and second input values and half the difference between the first and second input value, and wherein during the computing, a DC basis function is maintained to be flat by applying a set of the lifted butterfly operations initially on the N inputs values and then recursively on low pass outputs of a previous stage, and by arranging the ordered set of operations such that the DC coefficient of the DCT coefficients is substantially equal to the average value of the N inputs values.