US 9,813,716 B2
Video encoder and video encoding method
Hidenobu Miyoshi, Kawasaki (JP)
Assigned to FUJITSU LIMITED, Kawasaki (JP)
Filed by FUJITSU LIMITED, Kawasaki-shi, Kanagawa (JP)
Filed on Oct. 31, 2014, as Appl. No. 14/529,635.
Claims priority of application No. 2013-248567 (JP), filed on Nov. 29, 2013.
Prior Publication US 2015/0156486 A1, Jun. 4, 2015
Int. Cl. H04N 19/176 (2014.01); H04N 19/11 (2014.01); H04N 19/159 (2014.01); H04N 19/167 (2014.01); H04N 19/44 (2014.01); H04N 19/66 (2014.01); H04N 19/107 (2014.01); H04N 19/593 (2014.01)
CPC H04N 19/176 (2014.11) [H04N 19/11 (2014.11); H04N 19/159 (2014.11); H04N 19/167 (2014.11); H04N 19/44 (2014.11); H04N 19/66 (2014.11); H04N 19/107 (2014.11); H04N 19/593 (2014.11)] 20 Claims
OG exemplary drawing
 
1. A video encoder that encodes a coding-target picture included in a video in an intra-refresh scheme in which a slice is cyclically shifted across a picture included in the video in a certain refresh cycle and each pixel in the slice is encoded with reference to the slice or a refreshed region through which the slice has traversed, the video encoder comprising:
a processor configured to: when a coding-target block included in the refreshed region in the coding-target picture is encoded in accordance with an intra-prediction coding mode in which a prediction block for the coding-target block is generated by using information on an encoded region in the coding-target picture and an error signal between the coding-target block and the prediction block is encoded, for each of a plurality of possible sizes of a first sub-block in the coding-target block, the first sub-block being a unit for generating the prediction block, among a plurality of prediction modes with different reference ranges of encoded pixels to be referred to in generating the prediction block for the first sub-block, determine a prediction mode with the reference range not overlapping an unrefreshed region, which corresponds to a region through which the slice has not traversed, as a valid prediction mode;
calculate, for each combination of a size of the first sub-block, a size of a second sub-block which includes the first sub-block and serves as a unit for application of the prediction mode, and the valid prediction mode, an estimation value of an amount of code when a third sub-block which includes the first sub-block and the second sub-block and serves as a unit for application of an intra prediction coding mode, is intra-prediction-encoded;
determine the combination of the size of the first sub-block, the size of the second sub-block, and the valid prediction mode with a smallest one of the estimation values, as an intra prediction mode;
generate coded data by encoding the third sub-block in accordance with the intra prediction mode; and
entropy-encode the coded data.