Patent ID: 9232224
Filing Date: 2016-01-05
CPC Classification: H04N

Claim Text:
1. An image encoding method, comprising: determining, by an intra prediction unit, an intra prediction mode for image or video data; generating, by the intra prediction unit, a prediction block; generating, by a transform/quantization unit, a residual block of the prediction block; transforming and quantizing, by the transform/quantization unit, the residual block to generate a quantized block; and entropy-coding, by an entropy coder, quantized coefficients of the quantized block, wherein, when a size of the quantized block is equal to 8×8, the coefficients of the quantized block are divided into a plurality of subsets, and the plurality of subsets are scanned using a scan pattern determined according to the intra prediction mode, wherein a scan pattern for scanning non-zero coefficients of each subset is same with the scan pattern for the plurality of subsets, wherein a scan pattern for scanning flags indicating non-zero coefficients of each subset is same with the scan pattern for scanning non-zero coefficients of each subset, wherein the intra prediction mode is encoded using a upper intra prediction mode and a left intra prediction mode, wherein when the upper intra prediction mode or the left intra prediction mode is unavailable, the upper intra prediction mode or the left intra prediction mode is set to a DC mode.