Patent ID: 8204116
Filing Date: 2012-06-19
Classification: H04N

Abstract:
1. A method for encoding a video signal representing at least one video frame, with the at least one video frame being composed of picture samples, the picture samples belonging either to a top or a bottom field of alternate rows of the video frame, being captured at different time instants, the video frame being spatially divided up into macroblock pair regions, each macroblock pair region being associated with a top and a bottom macroblock, the method comprising the following steps being performed by an encoder: deciding, for each macroblock pair region, as to whether the respective macroblock pair region is of a frame coded or a field coded distribution type; assigning, for each macroblock pair region, each of the pixel samples in the respective macroblock pair region to a respective one of the top and bottom macroblock of the respective macroblock pair region, in accordance with the distribution type of the respective macroblock pair region, such that, in accordance with the frame coded distribution type, pixel samples lying in an upper part of the respective macroblock pair region are assigned to the top macroblock and pixel samples lying in a lower part of the respective macroblock pair region are assigned to the bottom macroblock, whereas, in accordance with the field coded distribution type, pixel samples in the respective macroblock pair region belonging to the top field are assigned to the top macroblock and pixel samples in the respective macroblock pair region belonging to the bottom field are assigned to the bottom macroblock; pre-coding the video signal into a pre-coded video signal, including transforming the macroblocks from spatial domain to frequency domain in units of sub-parts into which the macroblocks are partitioned, or smaller sub-units partitioning, in turn, the sub-parts to obtain, for each macroblock, a syntax element for the respective macroblock, specifying, for a predetermined sub-part of the current macroblock, as to whether the predetermined sub-part corresponds to a set of transform coefficients comprising at least one non-zero transform coefficient; determining, for the syntax element of a current macroblock associated with a current macroblock pair region of the macroblock pair regions, assigning one of at least two context models to the current syntax element based on a pre-determined attribute of the neighboring macroblock, wherein each context model is associated with a different probability estimation; and arithmetically encoding the syntax element into a coded bit stream based on the probability estimation with which the assigned context model is associated.