Syntax: x265 [options] infile [-o] outfile infile can be YUV or Y4M outfile is raw HEVC bitstream Executable Options: -h/--help Show this help text and exit -V/--version Show version info and exit Output Options: -o/--output Bitstream output file name --log-level Logging level: none error warning info debug full. Default info --no-progress Disable CLI progress reports --[no-]cu-stats Enable logging stats about distribution of cu across all modes. Default disabled --csv Comma separated log file, log level >= 3 frame log, else one line per run Input Options: --input Raw YUV or Y4M input file name. `-` for stdin --y4m Force parsing of input stream as YUV4MPEG2 regardless of file extension --fps Source frame rate (float or num/denom), auto-detected if Y4M --input-res WxH Source picture size [w x h], auto-detected if Y4M --input-depth Bit-depth of input file. Default 8 --input-csp Source color space: i420, i444 or i422, auto-detected if Y4M. Default: i420 -f/--frames Maximum number of frames to encode. Default all --seek First frame to encode --[no-]interlace Indicate input pictures are interlace fields in temporal order. Default progressive --dither Enable dither if downscaling to 8 bit pixels. Default disabled Quality reporting metrics: --[no-]ssim Enable reporting SSIM metric scores. Default disabled --[no-]psnr Enable reporting PSNR metric scores. Default disabled Profile, Level, Tier: --profile Enforce an encode profile: main, main10, mainstillpicture --level-idc Force a minumum required decoder level (as '5.0' or '50') --[no-]high-tier If a decoder level is specified, this modifier selects High tier of that level Threading, performance: --threads Number of threads for thread pool (0: detect CPU core count, default) -F/--frame-threads Number of concurrently encoded frames. 0: auto-determined by core count --[no-]wpp Enable Wavefront Parallel Processing. Default enabled --[no-]pmode Parallel mode analysis. Default disabled --[no-]pme Parallel motion estimation. Default disabled --[no-]asm Override CPU detection. Default: auto Presets: -p/--preset Trade off performance for compression efficiency. Default medium ultrafast, superfast, veryfast, faster, fast, medium, slow, slower, veryslow, or placebo -t/--tune Tune the settings for a particular type of source or situation: psnr, ssim, zerolatency, or fastdecode Quad-Tree size and depth: -s/--ctu <64|32|16> Maximum CU size (default: 64x64). Default 64 --tu-intra-depth Max TU recursive depth for intra CUs. Default 1 --tu-inter-depth Max TU recursive depth for inter CUs. Default 1 --[no-]rect Enable rectangular motion partitions Nx2N and 2NxN. Default disabled --[no-]amp Enable asymmetric motion partitions, requires --rect. Default disabled Analysis: --rd <0..6> Level of RD in mode decision 0:least....6:full RDO. Default 3 --psy-rd <0..2.0> Strength of psycho-visual rate distortion optimization, 0 to disable. Default 0.000000 --psy-rdoq <0..50.0> Strength of psycho-visual optimization in quantization, 0 to disable. Default 0.000000 --nr An integer value in range of 100 to 1000, which denotes strength of noise reduction. Default disabled --[no-]tskip-fast Enable fast intra transform skipping. Default disabled --[no-]early-skip Enable early SKIP detection. Default disabled --[no-]fast-cbf Enable early outs based on whether residual is coded. Default disabled Coding tools: -w/--[no-]weightp Enable weighted prediction in P slices. Default enabled --[no-]weightb Enable weighted prediction in B slices. Default disabled --[no-]cu-lossless Consider lossless mode in CU RDO decisions. Default disabled --[no-]signhide Hide sign bit of one coeff per TU (rdo). Default enabled --[no-]tskip Enable intra 4x4 transform skipping. Default disabled Temporal / motion search options: --me Motion search method dia hex umh star full. Default 1 -m/--subme Amount of subpel refinement to perform (0:least .. 7:most). Default 2 --merange Motion search range. Default 57 --max-merge <1..5> Maximum number of merge candidates. Default 2 --[no-]temporal-mvp Enable temporal MV predictors. Default enabled Spatial / intra options: --[no-]strong-intra-smoothing Enable strong intra smoothing for 32x32 blocks. Default enabled --[no-]constrained-intra Constrained intra prediction (use only intra coded reference pixels) Default disabled --[no-]b-intra Enable intra in B frames in veryslow presets. Default disabled --[no-]fast-intra Enable faster search method for angular intra predictions. Default disabled --rdpenalty <0..2> penalty for 32x32 intra TU in non-I slices. 0:disabled 1:RD-penalty 2:maximum. Default 0 Slice decision options: --[no-]open-gop Enable open-GOP, allows I slices to be non-IDR. Default enabled -I/--keyint Max IDR period in frames. -1 for infinite-gop. Default 250 -i/--min-keyint Scenecuts closer together than this are coded as I, not IDR. Default: auto --no-scenecut Disable adaptive I-frame decision --scenecut How aggressively to insert extra I-frames. Default 40 --rc-lookahead Number of frames for frame-type lookahead (determines encoder latency) Default 20 --bframes Maximum number of consecutive b-frames (now it only enables B GOP structure) Default 4 --bframe-bias Bias towards B frame decisions. Default 0 --b-adapt <0..2> 0 - none, 1 - fast, 2 - full (trellis) adaptive B frame scheduling. Default 2 --[no-]b-pyramid Use B-frames as references. Default enabled --ref max number of L0 references to be allowed (1 .. 16) Default 3 --qpfile Force frametypes and QPs for some or all frames Format of each line: framenumber frametype QP QP is optional (none lets x265 choose). Frametypes: I,i,P,B,b. QPs are restricted by qpmin/qpmax. Rate control, Quantization: --bitrate Target bitrate (kbps) for ABR (implied). Default 0 -q/--qp QP for P slices in CQP mode (implied). --ipratio and --pbration determine other slice QPs --crf Quality-based VBR (0-51). Default 28.000000 --[no-]lossless Enable lossless: bypass transform, quant and loop filters globally. Default disabled --crf-max With CRF+VBV, limit RF to this value. Default 0.000000 May cause VBV underflows! --crf-min With CRF+VBV, limit RF to this value. Default 0.000000 this specifies a minimum rate factor value for encode! --vbv-maxrate Max local bitrate (kbit/s). Default 0 --vbv-bufsize Set size of the VBV buffer (kbit). Default 0 --vbv-init Initial VBV buffer occupancy (fraction of bufsize or in kbits). Default 0.900000 --aq-mode Mode for Adaptive Quantization - 0:none 1:uniform AQ 2:auto variance. Default 2 --aq-strength Reduces blocking and blurring in flat and textured areas.(0 to 3.0). Default 1.000000 --[no-]cutree Enable cutree for Adaptive Quantization. Default enabled --ipratio QP factor between I and P. Default 1.400000 --pbratio QP factor between P and B. Default 1.300000 --cbqpoffs Chroma Cb QP Offset. Default 0 --crqpoffs Chroma Cr QP Offset. Default 0 --stats Filename for stats file in multipass pass rate control. Default x265_2pass.log --pass Multi pass rate control. - 1 : First pass, creates stats file - 2 : Last pass, does not overwrite stats file - 3 : Nth pass, overwrites stats file --[no-]slow-firstpass Enable a slow first pass in a multipass rate control mode. Default disabled --analysis-mode save - Dump analysis info into file, load - Load analysis buffers from the file. Default 0 --analysis-file Specify file name used for either dumping or reading analysis data. --scaling-list Specify a file containing HM style quant scaling lists or 'default' or 'off'. Default: off --lambda-file Specify a file containing replacement values for the lambda tables MAX_MAX_QP+1 floats for lambda table, then again for lambda2 table Blank lines and lines starting with hash(#) are ignored Comma is considered to be white-space Loop filters (deblock and SAO): --[no-]lft Enable Deblocking Loop Filter. Default enabled --[no-]sao Enable Sample Adaptive Offset. Default enabled --[no-]sao-non-deblock Use non-deblocked pixels, else right/bottom boundary areas skipped. Default disabled VUI options: --sar Sample Aspect Ratio, the ratio of width to height of an individual pixel. Choose from 0=undef, 1=1:1("square"), 2=12:11, 3=10:11, 4=16:11, 5=40:33, 6=24:11, 7=20:11, 8=32:11, 9=80:33, 10=18:11, 11=15:11, 12=64:33, 13=160:99, 14=4:3, 15=3:2, 16=2:1 or custom ratio of . Default 0 --crop-rect Add 'left,top,right,bottom' to the bitstream-level cropping rectangle --overscan Specify whether it is appropriate for decoder to show cropped region: undef, show or crop. Default undef --videoformat Specify video format from undef, component, pal, ntsc, secam, mac. Default undef --range Specify black level and range of luma and chroma signals as full or limited Default limited --colorprim Specify color primaries from undef, bt709, bt470m, bt470bg, smpte170m, smpte240m, film, bt2020. Default undef --transfer Specify transfer characteristics from undef, bt709, bt470m, bt470bg, smpte170m, smpte240m, linear, log100, log316, iec61966-2-4, bt1361e, iec61966-2-1, bt2020-10, bt2020-12. Default undef --colormatrix Specify color matrix setting from undef, bt709, fcc, bt470bg, smpte170m, smpte240m, GBR, YCgCo, bt2020nc, bt2020c. Default undef --chromaloc Specify chroma sample location (0 to 5). Default of 0 Bitstream options: --[no-]info Emit SEI identifying encoder and parameters. Default enabled --[no-]aud Emit access unit delimiters at the start of each access unit. Default disabled --[no-]hrd Enable HRD parameters signalling. Default disabled --[no-]repeat-headers Emit SPS and PPS headers at each keyframe. Default disabled --hash Decoded Picture Hash SEI 0: disabled, 1: MD5, 2: CRC, 3: Checksum. Default 0 Reconstructed video options (debugging): -r/--recon Reconstructed raw image YUV or Y4M output file name --recon-depth Bit-depth of reconstructed raw image file. Defaults to input bit depth, or 8 if Y4M Full documentation may be found at http://x265.readthedocs.org/en/default/cli.html