QSV参数
"async_depth","Maximumprocessingparallelism"
"avbr_accuracy","AccuracyoftheAVBRratecontrol",
"avbr_convergence","ConvergenceoftheAVBRratecontrol"
"preset"
"veryfast"
"faster"
"fast"
"medium"
"slow"
"slower"
"veryslow"
"vcm","Usethevideoconferencingmoderatecontrol"
"rdo","Enableratedistortionoptimization"
"max_frame_size","Maximumencodedframesizeinbytes"
"max_slice_size","Maximumencodedslicesizeinbytes"
"bitrate_limit","Togglebitratelimitations"
"mbbrc","MBlevelbitratecontrol"
"extbrc","Extendedbitratecontrol"
"adaptive_i","AdaptiveI-frameplacement"
"adaptive_b","AdaptiveB-frameplacement"
"b_strategy","StrategytochoosebetweenI/P/B-frames"
"cavlc","EnableCAVLC"
"idr_interval","Distance(inI-frames)betweenIDRframes"
"pic_timing_sei","InsertpicturetimingSEIwithpic_struct_syntaxelement"
"single_sei_nal_unit","PutalltheSEImessagesintooneNALU"
"max_dec_frame_buffering","MaximumnumberofframesbufferedintheDPB"
"look_ahead","UseVBRalgorithmwithlookahead"
"look_ahead_depth","Depthoflookaheadinnumberframes"
"look_ahead_downsampling"
"unknown"
"off"
"2x"
"int_ref_type","Intrarefreshtype"
"none"
"vertical"
"int_ref_cycle_size","Numberofframesintheintrarefreshcycle"
"int_ref_qp_delta","QPdifferencefortherefreshMBs"
"recovery_point_sei","InsertrecoverypointSEImessages"
"trellis","Trellisquantization"
"off"
"I"
"P"
"B"
"profile"
"unknown"
"baseline"
"main"
"high"
"a53cc","UseA53ClosedCaptions(ifavailable)",