Merge　mode　is　a　new　tool　for　improving　inter-frame　coding　efficiency　in　high-efficiency　video　coding.　This　tool　can　save　the　bitrate　for　the　motion　vector　by　sharing　this　vector　with　neighboring　blocks.　Merge　is　a　process　that　selects　a　candidate　motion　vector　by　calculating　the　cost　of　rate-distortion.　However,　this　process　requires　a　large　number　of　complex　computations　and　memory　access,　thereby　resulting　in　the　low　efficiency　of　hardware　implementation.　This　paper　proposes　a　new　Merge　candidate　decision　scheme　that　determines　the　most　favorable　Merge　candidate　from　a　full　list　of　candidates　by　comparing　the　sum　of　absolute　transformed　difference　with　the　weighted　header　bit　instead　of　performing　a　complex　calculation　for　sum　of　squared　difference　and　entropy　coding　process　in　HM16.7.　The　simulation　results　show　that　the　performance　of　the　proposed　algorithm　is　close　to　that　of　HM16.7　and　increases　the　BD-rate　only　by　0.22–1.21%.　The　multilevel　pipelines　architecture　is　also　exploited　in　the　hardware　design.　The　weighted　header　bit　operation　is　performed　by　using　the　look-up　table,　which　reduces　both　the　complexity　and　encoding　clock　cycle.　The　designed　system　is　implemented　with　a　register　transfer　level　code.　The　synthesis　results　from　the　Design　Compiler　show　that　compared　with　other　architecture,　the　proposed　architecture　offers　great　advantages　in　resource　utilization　and　can　process　1920　×　1080　at　353 frame/s　for　P-slices　with　a　clock　frequency　of　1057 MHz　and　logic　gate　count　of　285.2 K.　©　2018,　Springer-Verlag　GmbH　Germany,　part　of　Springer　Nature.