xevcall about HEVCMenuSkip to contentHomeAboutStandardPosted byyongjoahnPosted onJanuary 23, 2014Posted underAll about HM encoderComments3 CommentsMotion estimation of HM encoderOverview of motion estimation (ME) of HM encoderTwo steps for pixel precisionsInteger-pel (TEncSearch::xPetternSearch() or TEncSearch::xPatternSearchFast())Sub-pel (TEncSearch::xPatternSearchFracDIF())Half-pelQuarter-pelTwo kinds of motion search algorithmFull search (TEncSearch::xPetternSearch())Test zone (TZ) search (TEncSearch::xPatternSearchFast()) (Default on)FIGURE. Overall ME flow of HM encoderTZ search for integer MEWhat is TZ searchCombined diamond search and raster search methodsProvides a good RD performance compared to full search, with more than 60% improvement in encoding time [1]JMVC software and HM software employ TZ search1. Select starting point for MEAMVP – HEVC (median – H.264/AVC)Three MVs of neighboring blocks (left, above, above-right) (Default off)Zero MV (Default on)2. First search & early termination (ET)8 points diamond search (Default on) or square searchCondition for ET: Max 3 rounds after the best matchFIGURE. Diamond search3. Raster refinement searchIf integer-pel distance is bigger than 5FIGURE. Raster refinement search4. Star refinement search & early termination (ET)8 points diamond search (Default on) or square search (with the center of the best match from the early two steps)Condition for ET: Max 2 rounds after the best matchSub-pel refinement MEHalf-pel refinement MEEight neighboring half-pels of best integer ME positionQuarter-pel refinement MEEight neighboring quarter-pels of best half-pel ME positionFIGURE. Sub-pel refinement MEStandardPosted byyongjoahnPosted onJanuary 22, 2014Posted underAll about HM encoderCommentsLeave a commentIntroduction of HM encoderIntroductionHEVC test model (HM)A reference software for High efficiency video coding (HEVC) standardizationMaintained by JCT-VC (ISO/IEC MPEG & ITU-T VCEG)Main purpose of HMExample implementation conformed to the HEVC standardSoftware basis to test and verify intermediated stage of the HEVC standardUsed to generated anchor dataHistoryJCT-VC 1st meeting (April, 2010) – Test Model under Consideration (TMuC)JCTVC-A124 (Samsung) raked 1st in HEVC CfPTMuC 0.1: selected tools of JCTVC-A124 + fast enc.TMuC 0.2: + HHI tools (RQT, MOMS, PIPE, etc.)TMuC 0.3: + Nokia/Cisco tools (LCEC, DIF, etc.)…TMuC 0.9: Last version of TMuCJCT-VC 3rd meeting (Oct., 2010) – HM 1.0JCT-VC 14th meeting (July, 2013) – HM 12.0ManagementSource is controlled by SVN (a software versioning and revision control system)https://hevc.hhi.fraunhofer.de/svn/svn_HEVCSoftware/ (main)http://hevc.kw.bbc.co.uk/svn/jctvc-tmuc/ (additional)Bugs are tracked through issue tracker (http://hevc.kw.bbc.co.uk/trac)Software coordinatorsF. Bossen (NTT DOCOMO, chair)D. Flynn (BBC, vice chair)K. Sϋring (HHI, vice chair)Block diagram of HM encoderTypical block-based hybrid codec structure + enhanced & additional toolsFI