Preset:
使用方法： -p/--preset <string>
1.ultrafast
param->lookaheadDepth = 5;
param->scenecutThreshold = 0; // disable lookahead
param->maxCUSize = 32;
param->minCUSize = 16;
param->bframes = 3;
param->bFrameAdaptive = 0;
param->subpelRefine = 0;
param->searchMethod = X265_DIA_SEARCH;
param->bEnableEarlySkip = 1; //为了减小CU递归深度，提前终止CU划分，默认打开
param->bEnableSAO = 0;
param->bEnableSignHiding = 0; //Intra直接编码残差块，不进行DCT，默认关闭
param->bEnableWeightedPred = 0; //B slice中使用加权预测，默认关闭
param->rdLevel = 2; //提前终止不必要的模式决策，默认关闭
param->maxNumReferences = 1;
param->limitReferences = 0;
param->rc.aqStrength = 0.0;
param->rc.aqMode = X265_AQ_NONE;
param->rc.qgSize = 32;
param->bEnableFastIntra = 1; //跳过帧内DCT
2.superfast
param->lookaheadDepth = 10;
param->maxCUSize = 32;
param->bframes = 3;
param->bFrameAdaptive = 0;
param->subpelRefine = 1;
param->bEnableEarlySkip = 1;
param->bEnableWeightedPred = 0;
param->rdLevel = 2;
param->maxNumReferences = 1;
param->limitReferences = 0;
param->rc.aqStrength = 0.0;
param->rc.aqMode = X265_AQ_NONE;
param->rc.qgSize = 32;
param->bEnableSAO = 0;
param->bEnableFastIntra = 1;
3.veryfast
param->lookaheadDepth = 15;
param->bFrameAdaptive = 0;
param->subpelRefine = 1;
param->bEnableEarlySkip = 1;
param->rdLevel = 2;
param->maxNumReferences = 2;
param->rc.qgSize = 32;
param->bEnableFastIntra = 1;
4.faster
param->lookaheadDepth = 15;
param->bFrameAdaptive = 0;
param->bEnableEarlySkip = 1;
param->rdLevel = 2;
param->maxNumReferences = 2;
param->bEnableFastIntra = 1;
5.fast
param->lookaheadDepth = 15;
param->bFrameAdaptive = 0;
param->rdLevel = 2;
param->maxNumReferences = 3;
param->bEnableFastIntra = 1;
6.medium
/* defaults */
7.slow
param->bEnableRectInter = 1;
param->lookaheadDepth = 25;
param->rdLevel = 4;
param->rdoqLevel = 2;
param->psyRdoq = 1.0;
param->subpelRefine = 3;
param->maxNumMergeCand = 3;
param->searchMethod = X265_STAR_SEARCH;
param->maxNumReferences = 4;
param->limitModes = 1;
param->lookaheadSlices = 4; // limit parallelism as already enough work exists
8.slower
param->bEnableWeightedBiPred = 1;
param->bEnableAMP = 1;
param->bEnableRectInter = 1;
param->lookaheadDepth = 30;
param->bframes = 8;
param->tuQTMaxInterDepth = 2;
param->tuQTMaxIntraDepth = 2;
param->rdLevel = 6;
param->rdoqLevel = 2;
param->psyRdoq = 1.0;
param->subpelRefine = 3;
param->maxNumMergeCand = 3;
param->searchMethod = X265_STAR_SEARCH;
param->maxNumReferences = 4;
param->limitReferences = 2;
param->limitModes = 1;
param->bIntraInBFrames = 1;
param->lookaheadSlices = 4; // limit parallelism as already enough work exists
param->limitTU = 4;
9.veryslow
param->bEnableWeightedBiPred = 1;
param->bEnableAMP = 1;
param->bEnableRectInter = 1;
param->lookaheadDepth = 40;
param->bframes = 8;
param->tuQTMaxInterDepth = 3;
param->tuQTMaxIntraDepth = 3;
param->rdLevel = 6;
param->rdoqLevel = 2;
param->psyRdoq = 1.0;
param->subpelRefine = 4;
param->maxNumMergeCand = 4;
param->searchMethod = X265_STAR_SEARCH;
param->maxNumReferences = 5;
param->limitReferences = 1;
param->limitModes = 1;
param->bIntraInBFrames = 1;
param->lookaheadSlices = 0; // disabled for best quality
param->limitTU = 4;
10.placebo
param->bEnableWeightedBiPred = 1;
param->bEnableAMP = 1;
param->bEnableRectInter = 1;
param->lookaheadDepth = 60;
param->searchRange = 92;
param->bframes = 8;
param->tuQTMaxInterDepth = 4;
param->tuQTMaxIntraDepth = 4;
param->rdLevel = 6;
param->rdoqLevel = 2;
param->psyRdoq = 1.0;
param->subpelRefine = 5;
param->maxNumMergeCand = 5;
param->searchMethod = X265_STAR_SEARCH;
param->bEnableTransformSkip = 1;
param->bEnableRecursionSkip = 0;
param->maxNumReferences = 5;
param->limitReferences = 0;
param->bIntraInBFrames = 1;
param->lookaheadSlices = 0; // disabled for best quality
// TODO: optimized esa
Tune: 建议使用 –tune，否则结果不能用于比较
使用方法： -t/--tune <string>
1.psnr
param->rc.aqStrength = 0.0;
param->psyRd = 0.0;
param->psyRdoq = 0.0;
2.ssim
param->rc.aqMode = X265_AQ_AUTO_VARIANCE;
param->psyRd = 0.0;
param->psyRdoq = 0.0;
3.fastdecode or fast-decode
param->bEnableLoopFilter = 0;
param->bEnableSAO = 0;
param->bEnableWeightedPred = 0;
param->bEnableWeightedBiPred = 0;
param->bIntraInBFrames = 0;
4.zerolatency or zero-latency
param->bFrameAdaptive = 0;
param->bframes = 0;
param->lookaheadDepth = 0;
param->scenecutThreshold = 0;
param->rc.cuTree = 0;
param->frameNumThreads = 1;
5.grain
param->rc.ipFactor = 1.1;
param->rc.pbFactor = 1.0;
param->rc.cuTree = 0;
param->rc.aqMode = 0;
param->rc.qpStep = 1;
param->rc.bEnableGrain = 1;
param->bEnableRecursionSkip = 0;
param->psyRd = 4.0;
param->psyRdoq = 10.0;
param->bEnableSAO = 0;
param->rc.bEnableConstVbv = 1;