US 9,813,713 B2
Arithmetic decoding device, arithmetic decoding method, arithmetic coding device, arithmetic coding method, and storage medium
Takeshi Tsukuba, Sakai (JP); Tomohiro Ikai, Sakai (JP); and Tomoyuki Yamamoto, Sakai (JP)
Assigned to SHARP KABUSHIKI KAISHA, Sakai (JP)
Filed by Sharp Kabushiki Kaisha, Sakai, Osaka (JP)
Filed on Oct. 19, 2016, as Appl. No. 15/297,207.
Application 15/297,207 is a continuation of application No. 15/000,174, filed on Jan. 19, 2016, granted, now 9,516,333.
Application 15/000,174 is a continuation of application No. 14/408,699, granted, now 9,307,264, issued on Apr. 5, 2016, previously published as PCT/JP2013/065423, filed on Jun. 4, 2013.
Claims priority of application No. 2012-141416 (JP), filed on Jun. 22, 2012.
Prior Publication US 2017/0099488 A1, Apr. 6, 2017
Int. Cl. G06K 9/46 (2006.01); H04N 19/124 (2014.01); H04N 19/46 (2014.01); H04N 19/60 (2014.01); H04N 19/129 (2014.01); H04N 19/122 (2014.01); H04N 19/91 (2014.01); H04N 19/70 (2014.01); H04N 19/182 (2014.01); H04N 19/176 (2014.01)
CPC H04N 19/124 (2014.11) [H04N 19/122 (2014.11); H04N 19/129 (2014.11); H04N 19/46 (2014.11); H04N 19/60 (2014.11); H04N 19/70 (2014.11); H04N 19/91 (2014.11); H04N 19/176 (2014.11); H04N 19/182 (2014.11)] 6 Claims
OG exemplary drawing
 
1. An arithmetic decoding device which decodes coded data of each transform coefficient which is obtained by performing frequency transform on a target image for each unit domain and each transform coefficient obtained through a transform skip or a transform/quantization bypass, the device comprising:
a context index deriving circuit that derives a context index of a nonzero transform coefficient presence/absence flag indicating whether or not the transform coefficient is 0 in a unit domain; and
a syntax decoding circuit that arithmetically decodes the non-zero transform coefficient presence/absence flag by referring to the derived context index,
wherein, in a case where a transform skip flag or the transform/quantization bypass flag is 1, the context index deriving circuit derives a context index which is common to transform unit sizes of 4×4 to 32×32, the context index being in relation to a non-zero coefficient presence/absence flag corresponding to each transform coefficient obtained by the transform skip or the transform/quantization bypass.