1 .TH X265 "1" "AUGUST 2014" "v1.4" "User Commands"
3 x265 \- H.265/HEVC video encoder
6 .B x265 \fR[options] \fIinfile \fR[\-o] \fIoutfile
10 .B x265\-10bit \fR[options] \fIinfile \fR[\-o] \fIoutfile
14 infile can be YUV or Y4M
16 outfile is raw HEVC bitstream
19 Increasing demand for high definition and ultra\-high definition video,
20 along with an increasing desire for video on demand has led to
21 exponential growth in demand for bandwidth and storage requirements.
22 These challenges can be met by the new High Efficiency Video Coding
23 (HEVC) standard, also known as H.265. The x265 HEVC encoder project was
24 launched by MulticoreWare in 2013, aiming to provide the most efficient,
25 highest performance HEVC video encoder.
27 The High Efficiency Video Coding (HEVC) was developed by the ISO/IEC
28 Moving Picture Experts Group (MPEG) and ITU\-T Video Coding Experts Group
29 (VCEG), through their Joint Collaborative Team on Video Coding (JCT\-VC).
30 HEVC is also known as ISO/IEC 23008\-2 MPEG\-H Part 2 and ITU\-T H.265.
31 HEVC provides superior video quality and up to twice the data
32 compression as the previous standard (H.264/MPEG\-4 AVC). HEVC can
33 support 8K Ultra High Definition video, with a picture size up to
36 The primary objective of x265 is to become the best H.265/HEVC encoder
37 available anywhere, offering the highest compression efficiency and the
38 highest performance on a wide variety of hardware platforms. The x265
39 encoder is available as an open source library, published under the
40 GPLv2 license. It is also available under a commercial license, enabling
41 commercial companies to utilize and distribute x265 in their solutions
42 without being subject to the restrictions of the GPL license.
47 Show this help text and exit
50 Show version info and exit
54 \fB\-\-output <filename>
55 Bitstream output file name
57 \fB\-\-log\-level <string>
58 Logging level: none error warning info debug full. Default info
61 Disable CLI progress reports
63 \fB\-\-[no\-]cu\-stats
64 Enable logging stats about distribution of cu across all modes. Default disabled
67 Comma separated log file, log level >= 3 frame log, else one line per run
71 \fB\-\-input <filename>
72 Raw YUV or Y4M input file name. `\-` for stdin
75 Force parsing of input stream as YUV4MPEG2 regardless of file extension
77 \fB\-\-fps <float|rational>
78 Source frame rate (float or num/denom), auto\-detected if Y4M
81 Source picture size [w x h], auto\-detected if Y4M
83 \fB\-\-input\-depth <integer>
84 Bit\-depth of input file. Default 8
86 \fB\-\-input\-csp <string>
87 Source color space: i420, i444 or i422, auto\-detected if Y4M. Default: i420
89 \fB\-f/\-\-frames <integer>
90 Maximum number of frames to encode. Default all
95 \fB\-\-[no\-]interlace <bff|tff>
96 Indicate input pictures are interlace fields in temporal order. Default progressive
99 Enable dither if downscaling to 8 bit pixels. Default disabled
101 .SS "Quality reporting metrics:"
104 Enable reporting SSIM metric scores. Default disabled
107 Enable reporting PSNR metric scores. Default disabled
109 .SS "Profile, Level, Tier:"
111 \fB\-\-profile <string>
112 Enforce an encode profile: main, main10, mainstillpicture
114 \fB\-\-level\-idc <integer|float>
115 Force a minumum required decoder level (as '5.0' or '50')
117 \fB\-\-[no\-]high\-tier
118 If a decoder level is specified, this modifier selects High tier of that level
120 .SS "Threading, performance:"
122 \fB\-\-threads <integer>
123 Number of threads for thread pool (0: detect CPU core count, default)
125 \fB\-F/\-\-frame\-threads <integer>
126 Number of concurrently encoded frames. 0: auto\-determined by core count
129 Enable Wavefront Parallel Processing. Default enabled
132 Parallel mode analysis. Default disabled
135 Parallel motion estimation. Default disabled
137 \fB\-\-[no\-]asm <bool|int|string>
138 Override CPU detection. Default: auto
142 \fB\-p/\-\-preset <string>
143 Trade off performance for compression efficiency. Default medium
145 ultrafast, superfast, veryfast, faster, fast, medium, slow, slower, veryslow, or placebo
147 \fB\-t/--tune <string>
148 Tune the settings for a particular type of source or situation:"
150 psnr, ssim, zerolatency, or fastdecode
152 .SS "Quad-Tree size and depth:"
154 \fB\-s/\-\-ctu <64|32|16>
155 Maximum CU size (default: 64x64). Default 64
157 \fB\-\-tu\-intra\-depth <integer>
158 Max TU recursive depth for intra CUs. Default 1
160 \fB\-\-tu\-inter\-depth <integer>
161 Max TU recursive depth for inter CUs. Default 1
164 Enable rectangular motion partitions Nx2N and 2NxN. Default disabled
167 Enable asymmetric motion partitions, requires \fB\-\-rect\fR. Default disabled
170 Level of RD in mode decision 0:least....6:full RDO. Default 3
172 \fB\-\-psy\-rd <0..2.0>
173 Strength of psycho\-visual rate distortion optimization, 0 to disable. Default 0.000000
175 \fB\-\-psy\-rdoq <0..50.0>
176 Strength of psycho\-visual optimization in quantization, 0 to disable. Default 0.000000
179 An integer value in range of 100 to 1000, which denotes strength of noise reduction. Default disabled
181 \fB\-\-[no\-]tskip\-fast
182 Enable fast intra transform skipping. Default disabled
184 \fB\-\-[no\-]early\-skip
185 Enable early SKIP detection. Default disabled
187 \fB\-\-[no\-]fast\-cbf
188 Enable early outs based on whether residual is coded. Default disabled
192 \fB\-w/\-\-[no\-]weightp
193 Enable weighted prediction in P slices. Default enabled
196 Enable weighted prediction in B slices. Default disabled
198 \fB\-\-[no\-]cu-lossless
199 Consider lossless mode in CU RDO decisions. Default disabled
201 \fB\-\-[no\-]signhide
202 Hide sign bit of one coeff per TU (rdo). Default enabled
205 Enable intra transform skipping. Default disabled
207 .SS "Temporal / motion search options:"
210 Motion search method dia hex umh star full. Default 1
212 \fB\-m/\-\-subme <integer>
213 Amount of subpel refinement to perform (0:least .. 7:most). Default 2
215 \fB\-\-merange <integer>
216 Motion search range. Default 57
218 \fB\-\-max\-merge <1..5>
219 Maximum number of merge candidates. Default 2
221 \fB\-\-[no\-]temporal\-mvp
222 Enable temporal MV predictors. Default enabled
224 .SS "Spatial / intra options:"
226 \fB\-\-[no\-]strong\-intra\-smoothing
227 Enable strong intra smoothing for 32x32 blocks. Default enabled
229 \fB\-\-[no\-]constrained\-intra
230 Constrained intra prediction (use only intra coded reference pixels) Default disabled
232 \fB\-\-[no\-]b\-intra
233 Enable intra in B frames in veryslow presets. Default disabled
235 \fB\-\-[no\-]fast\-intra
236 Enable faster search method for angular intra predictions. Default disabled
238 \fB\-\-rdpenalty <0..2>
239 penalty for 32x32 intra TU in non\-I slices. 0:disabled 1:RD\-penalty 2:maximum. Default 0
241 .SS "Slice decision options:"
243 \fB\-\-[no\-]open\-gop
244 Enable open\-GOP, allows I slices to be non\-IDR. Default enabled
246 \fB\-I/\-\-keyint <integer>
247 Max IDR period in frames. \-1 for infinite\-gop. Default 250
249 \fB\-i/\-\-min\-keyint <integer>
250 Scenecuts closer together than this are coded as I, not IDR. Default: auto
253 Disable adaptive I\-frame decision
255 \fB\-\-scenecut <integer>
256 How aggressively to insert extra I\-frames. Default 40
258 \fB\-\-rc\-lookahead <integer>
259 Number of frames for frame\-type lookahead (determines encoder latency) Default 20
261 \fB\-\-bframes <integer>
262 Maximum number of consecutive b\-frames (now it only enables B GOP structure) Default 4
264 \fB\-\-bframe\-bias <integer>
265 Bias towards B frame decisions. Default 0
267 \fB\-\-b\-adapt <0..2>
268 0 \- none, 1 \- fast, 2 \- full (trellis) adaptive B frame scheduling. Default 2
270 \fB\-\-[no\-]b\-pyramid
271 Use B\-frames as references. Default enabled
274 max number of L0 references to be allowed (1 .. 16) Default 3
276 \fB\-\-qpfile <string>
277 Force frametypes and QPs for some or all frames
279 Format of each line: framenumber frametype QP
281 QP is optional (none lets x265 choose). Frametypes: I,i,P,B,b.
283 QPs are restricted by qpmin/qpmax.
286 .SS "Rate control, Quantization:"
288 \fB\-\-bitrate <integer>
289 Target bitrate (kbps) for ABR (implied). Default 0
292 Quality\-based VBR (0\-51). Default 28.000000
294 \fB\-\-[no\-]lossless
295 Enable lossless: bypass transform, quant and loop filters globally. Default disabled
297 \fB\-\-crf\-max <float>
298 With CRF+VBV, limit RF to this value. Default 0.000000
300 May cause VBV underflows!
302 \fB\-\-crf\-min <float>
303 With CRF+VBV, limit RF to this value. Default 0.000000
305 this specifies a minimum rate factor value for encode!
307 \fB\-\-vbv\-maxrate <integer>
308 Max local bitrate (kbit/s). Default 0
310 \fB\-\-vbv\-bufsize <integer>
311 Set size of the VBV buffer (kbit). Default 0
313 \fB\-\-vbv\-init <float>
314 Initial VBV buffer occupancy (fraction of bufsize or in kbits). Default 0.900000
316 \fB\-\-aq\-mode <integer>
317 Mode for Adaptive Quantization \- 0:none 1:uniform AQ 2:auto variance. Default 2
319 \fB\-\-aq\-strength <float>
320 Reduces blocking and blurring in flat and textured areas.(0 to 3.0). Default 1.000000
323 Enable cutree for Adaptive Quantization. Default enabled
325 \fB\-\-ipratio <float>
326 QP factor between I and P. Default 1.400000
328 \fB\-\-pbratio <float>
329 QP factor between P and B. Default 1.300000
331 \fB\-\-cbqpoffs <integer>
332 Chroma Cb QP Offset. Default 0
334 \fB\-\-crqpoffs <integer>
335 Chroma Cr QP Offset. Default 0
338 Filename for stats file in multipass pass rate control. Default x265_2pass.log
341 Multi pass rate control.
343 \- 1 : First pass, creates stats file
345 \- 2 : Last pass, does not overwrite stats file
347 \- 3 : Nth pass, overwrites stats file
349 \fB\-\-[no\-]slow\-firstpass
350 Enable a slow first pass in a multipass rate control mode. Default disabled
352 \fB\-\-analysis\-mode <string|int>
353 save \- Dump analysis info into file, load \- Load analysis buffers from the file. Default 0
355 \fB\-\-analysis-file <filename>
356 Specify file name used for either dumping or reading analysis data.
358 \fB\-\-scaling\-list <string>
359 Specify a file containing HM style quant scaling lists or 'default' or 'off'. Default: off
361 \fB\-\-lambda\-file <string>
362 Specify a file containing replacement values for the lambda tables
364 MAX_MAX_QP+1 floats for lambda table, then again for lambda2 table
366 Blank lines and lines starting with hash(#) are ignored
368 Comma is considered to be white-space
370 .SS "Loop filters (deblock and SAO):"
373 Enable Deblocking Loop Filter. Default enabled
376 Enable Sample Adaptive Offset. Default enabled
378 \fB\-\-[no\-]sao\-non\-deblock
379 Use non\-deblocked pixels, else right/bottom boundary areas skipped. Default disabled
383 \fB\-\-sar <width:height|int>
384 Sample Aspect Ratio, the ratio of width to height of an individual pixel.
386 Choose from 0=undef, 1=1:1("square"), 2=12:11, 3=10:11, 4=16:11,
387 5=40:33, 6=24:11, 7=20:11, 8=32:11, 9=80:33, 10=18:11, 11=15:11,
388 12=64:33, 13=160:99, 14=4:3, 15=3:2, 16=2:1 or custom ratio of <int:int>. Default 0
390 \fB\-\-crop\-rect <string>
391 Add 'left,top,right,bottom' to the bitstream\-level cropping rectangle
393 \fB\-\-overscan <string>
394 Specify whether it is appropriate for decoder to show cropped region: undef, show or crop. Default undef
396 \fB\-\-videoformat <string>
397 Specify video format from undef, component, pal, ntsc, secam, mac. Default undef
399 \fB\-\-range <string>
400 Specify black level and range of luma and chroma signals as full or limited Default limited
402 \fB\-\-colorprim <string>
403 Specify color primaries from undef, bt709, bt470m, bt470bg, smpte170m,
404 smpte240m, film, bt2020. Default undef
406 \fB\-\-transfer <string>
407 Specify transfer characteristics from undef, bt709, bt470m, bt470bg, smpte170m,
408 smpte240m, linear, log100, log316, iec61966\-2\-4, bt1361e, iec61966\-2\-1,
409 bt2020\-10, bt2020\-12. Default undef
411 \fB\-\-colormatrix <string>
412 Specify color matrix setting from undef, bt709, fcc, bt470bg, smpte170m,
413 smpte240m, GBR, YCgCo, bt2020nc, bt2020c. Default undef
415 \fB\-\-chromaloc <integer>
416 Specify chroma sample location (0 to 5). Default of 0
418 .SS "Bitstream options:"
421 Emit SEI identifying encoder and parameters. Default enabled
424 Emit access unit delimiters at the start of each access unit. Default disabled
427 Enable HRD parameters signalling. Default disabled
429 \fB\-\-[no\-]repeat\-headers
430 Emit SPS and PPS headers at each keyframe. Default disabled
432 \fB\-\-hash <integer>
433 Decoded Picture Hash SEI 0: disabled, 1: MD5, 2: CRC, 3: Checksum. Default 0
435 .SS "Reconstructed video options (debugging):"
437 \fB\-r/\-\-recon <filename>
438 Reconstructed raw image YUV or Y4M output file name
440 \fB\-\-recon\-depth <integer>
441 Bit\-depth of reconstructed raw image file. Defaults to input bit depth, or 8 if Y4M
443 Copyright \(co 2013\-2014 MulticoreWare, Inc.
445 The x265 software is owned and copyrighted by MulticoreWare, Inc.
446 MulticoreWare is committed to offering the x265 software under the GNU
447 GPL v2 license. Companies who do not wish to integrate the x265
448 Software in their products under the terms of the GPL license can
449 contact MulticoreWare (\fIlicense@x265.com\fR) to obtain a commercial
450 license agreement. Companies who use x265 under the GPL may also wish
451 to work with MulticoreWare to accelerate the development of specific
452 features or optimized support for specific hardware or software
453 platforms, or to contract for support.
455 The GNU GPL v2 license or the x265 commercial license agreement govern
456 your rights to access the copyrighted x265 software source code, but do
457 not cover any patents that may be applicable to the function of binary
458 executable software created from the x265 source code. You are
459 responsible for understanding the laws in your country, and for
460 licensing all applicable patent rights needed for use or distribution of
461 software applications created from the x265 source code. A good place
462 to start is with the Motion Picture Experts Group \- Licensing Authority
463 \- HEVC Licensing Program.
465 x265 is a registered trademark of MulticoreWare, Inc. The x265 logo is
466 a trademark of MulticoreWare, and may only be used with explicit written
467 permission. All rights reserved.
471 \fIhttp://x265.readthedocs.org/en/default/cli.html\fR