Patent ID: 8537899
Filing Date: 2013-09-17
Classification: H04N

Abstract:
1. A method comprising accessing, by a processing unit, data of a video frame buffered in a memory space; for one or more macroblocks of the video frame: computing, by the processing unit, DC prediction values for each macroblock of the one or more macroblocks; adjusting, by the processing unit, DC coefficients of the one or more macroblocks by corresponding DC prediction values for each macroblock of the one or more macroblocks; compressing, by the processing unit, the data of each macroblock of the one or more macroblocks of the video frame; and calling, by the processing unit, a function operative to write a data word of the output stream to the memory space, the function operative to receive a position of the data word in the output stream, assembling, by the processing unit, the data word from selected portions of the data of one or more compressed macroblocks based on the position of the data word and starting bit values of the compressed macroblocks and writing, by the processing unit, the assembled data word to the memory space; writing, by the processing unit, the compressed data comprising the data word assembled from each macroblock of the one or more macroblocks onto an output stream; accessing, by the processing unit, a set of N input values of the block stored in the memory space; and computing, by the processing unit, 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, at least one or more of the ordered set of operations comprising a lifted butterfly operation; wherein the lifted butterfly operation 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 the ordered set of operations is arranged such that the DC coefficient of the DCT coefficients is substantially equal to the average value of the N inputs values.