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x264

NAME

x264 - fast h264 encoder

DESCRIPTION

x264 core:98 Ubuntu_2:0.98.1653+git88b90d9-3 Syntax: x264 [options] -o outfile infile [widthxheight]

Infile can be raw YUV 4:2:0 (in which case resolution is required),

or YUV4MPEG 4:2:0 (*.y4m), or Avisynth if compiled with support (no). or libav* formats if compiled with lavf support (yes) or ffms support (no).

Outfile type is selected by filename:

.264 -> Raw bytestream .mkv -> Matroska .flv -> Flash Video .mp4 -> MP4 if compiled with GPAC support (yes)

OPTIONS

-h, --help

List basic options

--longhelp

List more options

--fullhelp

List all options

Example usage:

Constant quality mode:

x264 --crf 24 -o <output> <input>

Two-pass with a bitrate of 1000kbps:

x264 --pass 1 --bitrate 1000 -o <output> <input> x264 --pass 2 --bitrate 1000 -o <output> <input>

Lossless:

x264 --crf 0 -o <output> <input>

Maximum PSNR at the cost of speed and visual quality:

x264 --preset placebo --tune psnr -o <output> <input>

Constant bitrate at 1000kbps with a 2 second-buffer:

x264 --vbv-bufsize 2000 --bitrate 1000 -o <output> <input>

Presets:

--profile

Force the limits of an H.264 profile [high] Overrides all settings. - baseline:

--no-8x8dct --bframes 0 --no-cabac --cqm flat --weightp 0 No interlaced. No lossless.

- main:

--no-8x8dct --cqm flat No lossless.

- high:

No lossless.

--preset

Use a preset to select encoding settings [medium] Overridden by user settings. - ultrafast:

--no-8x8dct --aq-mode 0 --b-adapt 0 --bframes 0 --no-cabac --no-deblock --no-mbtree --me dia --no-mixed-refs --partitions none --ref 1 --scenecut 0 --subme 0 --trellis 0 --no-weightb --weightp 0

- superfast:

--no-mbtree --me dia --no-mixed-refs --partitions i8x8,i4x4 --ref 1 --subme 1 --trellis 0 --weightp 0

- veryfast:

--no-mbtree --no-mixed-refs --ref 1 --subme 2 --trellis 0 --weightp 0

- faster:

--no-mixed-refs --rc-lookahead 20 --ref 2 --subme 4 --weightp 1

- fast:

--rc-lookahead 30 --ref 2 --subme 6

- medium:

Default settings apply.

- slow:

--b-adapt 2 --direct auto --me umh --rc-lookahead 50 --ref 5 --subme 8

- slower:

--b-adapt 2 --direct auto --me umh --partitions all --rc-lookahead 60 --ref 8 --subme 9 --trellis 2

- veryslow:

--b-adapt 2 --bframes 8 --direct auto --me umh --merange 24 --partitions all --ref 16 --subme 10 --trellis 2 --rc-lookahead 60

- placebo:

--bframes 16 --b-adapt 2 --direct auto --slow-firstpass --no-fast-pskip --me tesa --merange 24 --partitions all --rc-lookahead 60 --ref 16 --subme 10 --trellis 2

--tune

Tune the settings for a particular type of source or situation

Overridden by user settings. Multiple tunings are separated by commas. Only one psy tuning can be used at a time. - film (psy tuning):

--deblock -1:-1 --psy-rd <unset>:0.15

- animation (psy tuning):

--bframes {+2} --deblock 1:1 --psy-rd 0.4:<unset> --aq-strength 0.6 --ref {Double if >1 else 1}

- grain (psy tuning):

--aq-strength 0.5 --no-dct-decimate --deadzone-inter 6 --deadzone-intra 6 --deblock -2:-2 --ipratio 1.1 --pbratio 1.1 --psy-rd <unset>:0.25 --qcomp 0.8

- stillimage (psy tuning):

--aq-strength 1.2 --deblock -3:-3 --psy-rd 2.0:0.7

- psnr (psy tuning):

--aq-mode 0 --no-psy

- ssim (psy tuning):

--aq-mode 2 --no-psy

- fastdecode:

--no-cabac --no-deblock --no-weightb --weightp 0

- zerolatency:

--bframes 0 --force-cfr --rc-lookahead 0 --sync-lookahead 0 --sliced-threads

--slow-firstpass

Don't force these faster settings with --pass 1: --no-8x8dct --me dia --partitions none --ref 1 --subme {2 if >2 else unchanged} --trellis 0 --fast-pskip

Frame-type options:

-I, --keyint <integer>

Maximum GOP size [250]

-i, --min-keyint <integer>

Minimum GOP size [auto]

--no-scenecut

Disable adaptive I-frame decision

--scenecut <integer>

How aggressively to insert extra I-frames [40]

--intra-refresh

Use Periodic Intra Refresh instead of IDR frames

-b, --bframes <integer>

Number of B-frames between I and P [3]

--b-adapt <integer>

Adaptive B-frame decision method [1] Higher values may lower threading efficiency. - 0: Disabled - 1: Fast - 2: Optimal (slow with high --bframes)

--b-bias <integer>

Influences how often B-frames are used [0]

--b-pyramid <string>

Keep some B-frames as references [normal] - none: Disabled - strict: Strictly hierarchical pyramid - normal: Non-strict (not Blu-ray compatible)

--no-cabac

Disable CABAC

-r, --ref <integer>

Number of reference frames [3]

--no-deblock

Disable loop filter

-f, --deblock <alpha:beta>

Loop filter parameters [0:0]

--slices <integer>

Number of slices per frame; forces rectangular slices and is overridden by other slicing options

--slice-max-size <integer> Limit the size of each slice in bytes

--slice-max-mbs <integer> Limit the size of each slice in macroblocks

--tff

Enable interlaced mode (top field first)

--bff

Enable interlaced mode (bottom field first)

--constrained-intra

Enable constrained intra prediction.

--pulldown <string>

Use soft pulldown to change frame rate - none, 22, 32, 64, double, triple, euro (requires cfr input)

--fake-interlaced

Flag stream as interlaced but encode progressive. Makes it possible to encode 25p and 30p Blu-Ray streams. Ignored in interlaced mode.

Ratecontrol:

-q, --qp <integer>

Force constant QP (0-51, 0=lossless)

-B, --bitrate <integer>

Set bitrate (kbit/s)

--crf <float>

Quality-based VBR (0-51, 0=lossless) [23.0]

--rc-lookahead <integer> Number of frames for frametype lookahead [40]

--vbv-maxrate <integer> Max local bitrate (kbit/s) [0]

--vbv-bufsize <integer> Set size of the VBV buffer (kbit) [0]

--vbv-init <float>

Initial VBV buffer occupancy [0.9]

--crf-max <float>

With CRF+VBV, limit RF to this value May cause VBV underflows!

--qpmin <integer>

Set min QP [10]

--qpmax <integer>

Set max QP [51]

--qpstep <integer>

Set max QP step [4]

--ratetol <float>

Tolerance of ABR ratecontrol and VBV [1.0]

--ipratio <float>

QP factor between I and P [1.40]

--pbratio <float>

QP factor between P and B [1.30]

--chroma-qp-offset <integer>

QP difference between chroma and luma [0]

--aq-mode <integer>

AQ method [1] - 0: Disabled - 1: Variance AQ (complexity mask) - 2: Auto-variance AQ (experimental)

--aq-strength <float>

Reduces blocking and blurring in flat and textured areas. [1.0]

-p, --pass <integer>

Enable multipass ratecontrol - 1: First pass, creates stats file - 2: Last pass, does not overwrite stats file - 3: Nth pass, overwrites stats file

--stats <string>

Filename for 2 pass stats ["x264_2pass.log"]

--no-mbtree

Disable mb-tree ratecontrol.

--qcomp <float>

QP curve compression [0.60]

--cplxblur <float>

Reduce fluctuations in QP (before curve compression) [20.0]

--qblur <float>

Reduce fluctuations in QP (after curve compression) [0.5]

--zones <zone0>/<zone1>/...

Tweak the bitrate of regions of the video Each zone is of the form

<start frame>,<end frame>,<option> where <option> is either

q=<integer> (force QP)

or

b=<float> (bitrate multiplier)

--qpfile <string>

Force frametypes and QPs for some or all frames Format of each line: framenumber frametype QP QP of -1 lets x264 choose. Frametypes: I,i,P,B,b. QPs are restricted by qpmin/qpmax.

Analysis:

-A, --partitions <string>

Partitions to consider ["p8x8,b8x8,i8x8,i4x4"] - p8x8, p4x4, b8x8, i8x8, i4x4 - none, all (p4x4 requires p8x8. i8x8 requires --8x8dct.)

--direct <string>

Direct MV prediction mode ["spatial"] - none, spatial, temporal, auto

--no-weightb

Disable weighted prediction for B-frames

--weightp <integer>

Weighted prediction for P-frames [2] - 0: Disabled - 1: Blind offset - 2: Smart analysis

--me <string>

Integer pixel motion estimation method ["hex"] - dia: diamond search, radius 1 (fast) - hex: hexagonal search, radius 2 - umh: uneven multi-hexagon search - esa: exhaustive search - tesa: hadamard exhaustive search (slow)

--merange <integer>

Maximum motion vector search range [16]

--mvrange <integer>

Maximum motion vector length [-1 (auto)]

--mvrange-thread <int>

Minimum buffer between threads [-1 (auto)]

-m, --subme <integer>

Subpixel motion estimation and mode decision [7] - 0: fullpel only (not recommended) - 1: SAD mode decision, one qpel iteration - 2: SATD mode decision - 3-5: Progressively more qpel - 6: RD mode decision for I/P-frames - 7: RD mode decision for all frames - 8: RD refinement for I/P-frames - 9: RD refinement for all frames - 10: QP-RD - requires trellis=2, aq-mode>0

--psy-rd

Strength of psychovisual optimization ["1.0:0.0"] #1: RD (requires subme>=6) #2: Trellis (requires trellis, experimental)

--no-psy

Disable all visual optimizations that worsen both PSNR and SSIM.

--no-mixed-refs

Don't decide references on a per partition basis

--no-chroma-me

Ignore chroma in motion estimation

--no-8x8dct

Disable adaptive spatial transform size

-t, --trellis <integer>

Trellis RD quantization. Requires CABAC. [1] - 0: disabled - 1: enabled only on the final encode of a MB - 2: enabled on all mode decisions

--no-fast-pskip

Disables early SKIP detection on P-frames

--no-dct-decimate

Disables coefficient thresholding on P-frames

--nr <integer>

Noise reduction [0]

--deadzone-inter <int>

Set the size of the inter luma quantization deadzone [21]

--deadzone-intra <int>

Set the size of the intra luma quantization deadzone [11] Deadzones should be in the range 0 - 32.

--cqm <string>

Preset quant matrices ["flat"] - jvt, flat

--cqmfile <string>

Read custom quant matrices from a JM-compatible file Overrides any other --cqm* options.

--cqm4 <list>

Set all 4x4 quant matrices Takes a comma-separated list of 16 integers.

--cqm8 <list>

Set all 8x8 quant matrices Takes a comma-separated list of 64 integers.

--cqm4i, --cqm4p, --cqm8i, --cqm8p

Set both luma and chroma quant matrices

--cqm4iy, --cqm4ic, --cqm4py, --cqm4pc

Set individual quant matrices

Video Usability Info (Annex E): The VUI settings are not used by the encoder but are merely suggestions to the playback equipment. See doc/vui.txt for details. Use at your own risk.

--overscan <string>

Specify crop overscan setting ["undef"] - undef, show, crop

--videoformat <string>

Specify video format ["undef"] - component, pal, ntsc, secam, mac, undef

--fullrange <string>

Specify full range samples setting ["off"] - off, on

--colorprim <string>

Specify color primaries ["undef"] - undef, bt709, bt470m, bt470bg

smpte170m, smpte240m, film

--transfer <string>

Specify transfer characteristics ["undef"] - undef, bt709, bt470m, bt470bg, linear,

log100, log316, smpte170m, smpte240m

--colormatrix <string>

Specify color matrix setting ["undef"] - undef, bt709, fcc, bt470bg

smpte170m, smpte240m, GBR, YCgCo

--chromaloc <integer>

Specify chroma sample location (0 to 5) [0]

--nal-hrd <string>

Signal HRD information (requires vbv-bufsize) - none, vbr, cbr (cbr not allowed in .mp4)

--pic-struct

Force pic_struct in Picture Timing SEI

Input/Output:

-o, --output

Specify output file

--muxer <string>

Specify output container format ["auto"] - auto, raw, mkv, flv, mp4

--demuxer <string>

Specify input container format ["auto"] - auto, yuv, y4m, lavf

--index <string>

Filename for input index file

--sar width:height

Specify Sample Aspect Ratio

--fps <float|rational>

Specify framerate

--seek <integer>

First frame to encode

--frames <integer>

Maximum number of frames to encode

--level <string>

Specify level (as defined by Annex A)

-v, --verbose

Print stats for each frame

--no-progress

Don't show the progress indicator while encoding

--quiet

Quiet Mode

--psnr

Enable PSNR computation

--ssim

Enable SSIM computation

--threads <integer>

Force a specific number of threads

--sliced-threads

Low-latency but lower-efficiency threading

--thread-input

Run Avisynth in its own thread

--sync-lookahead <integer> Number of buffer frames for threaded lookahead

--non-deterministic

Slightly improve quality of SMP, at the cost of repeatability

--asm <integer>

Override CPU detection

--no-asm

Disable all CPU optimizations

--visualize

Show MB types overlayed on the encoded video

--dump-yuv <string>

Save reconstructed frames

--sps-id <integer>

Set SPS and PPS id numbers [0]

--aud

Use access unit delimiters

--force-cfr

Force constant framerate timestamp generation

--tcfile-in <string>

Force timestamp generation with timecode file

--tcfile-out <string>

Output timecode v2 file from input timestamps

--timebase <int/int>

Specify timebase numerator and denominator

<integer>

Specify timebase numerator for input timecode file or specify timebase denominator for other input

built on Oct 5 2010, gcc: 4.4.5