View source for Documentation:Modules/x264

<span class="hatnote">This page is about the H.264 encoder. Were you looking for {{docmod|h26x}}, the H.264 decoder?</span>
{{See also|Documentation:Modules/x265}}
{{Module|name=x264|type=Muxer|first_version=0.7.2|description=[[H.264/MPEG-4 AVC|H.264/MPEG-4 Part 10/AVC]] encoder ([[x264]])}}

== Options ==
=== Frame-type ===
{{Option
|name=sout-x264-keyint
|value=integer
|default=250
|description=Maximum [[GOP]] size
}}
{{Option
|name=sout-x264-min-keyint
|value=integer
|default=25
|description=Minimum GOP size
}}
{{Option
|name=sout-x264-opengop
|value=boolean
|default=disabled
|description=Use recovery points to close GOPs
}}
{{Option
|name=sout-x264-bluray-compat
|value=boolean
|default=disabled
|description=Enable compatibility hacks for Blu-ray support
}}
{{Option
|name=sout-x264-scenecut
|value=integer
|default=40
|min=-1
|max=100
|description=Extra [[I-frame]]s aggressivity
}}
{{Option
|name=sout-x264-bframes
|value=integer
|default=3
|min=0
|max=16
|description=[[B-frame]]s between I and [[P-frame|P]]
}}
{{Option
|name=sout-x264-b-adapt
|value=integer
|default=1
|min=0
|max=2
|description=Adaptive B-frame decision
}}
{{Option
|name=sout-x264-b-bias
|value=integer
|default=0
|min=-100
|max=100
|description=Influence (bias) B-frames usage
}}
{{Option
|name=sout-x264-bpyramid
|value=string
|default="normal"
|select={none,strict,normal}
|description=Keep some B-frames as references
}}
{{Option
|name=sout-x264-cabac
|value=boolean
|default=enabled
|description=[[wikipedia:Context-adaptive binary arithmetic coding|CABAC]]
}}
{{Option
|name=sout-x264-fullrange
|value=boolean
|default=disabled
|description=Use fullrange instead of TV colorrange
}}
{{Option
|name=sout-x264-ref
|value=integer
|default=3
|min=1
|max=16
|description=Number of reference frames
}}
{{Option
|name=sout-x264-nf
|value=boolean
|default=disabled
|description=Skip loop filter
}}
{{Option
|name=sout-x264-deblock
|value=string
|default="0:0"
|description=Loop filter AlphaC0 and Beta parameters alpha:beta
}}
{{Option
|name=sout-x264-psy-rd
|value=string
|default="1.0:0.0"
|description=Strength of psychovisual optimization
}}
{{Option
|name=sout-x264-psy
|value=boolean
|default=enabled
|description=Use Psy-optimizations
}}
{{Option
|name=sout-x264-level
|value=string
|default="0"
|description=[[H.264]] level
}}
{{Option
|name=sout-x264-profile
|value=string
|default="high"
|description=H.264 profile
}}
{{Option
|name=sout-x264-interlaced
|value=boolean
|default=disabled
|description=[[Interlaced]] mode
}}
{{Option
|name=sout-x264-frame-packing<span id="select_sout-x264-frame-packing"></span>
|value=integer
|default=-1
|select=[[#appendix_select_sout-x264-frame-packing|{-1,0,1,2,3,4,5,6}]]
|description=Frame packing
}}
{{Option
|name=sout-x264-slices
|value=integer
|default=0
|description=Force number of slices per frame
}}
{{Option
|name=sout-x264-slice-max-size
|value=integer
|default=0
|description=Limit the size of each slice in bytes
}}
{{Option
|name=sout-x264-slice-max-mbs
|value=integer
|default=0
|description=Limit the size of each slice in macroblocks
}}
{{Option
|name=sout-x264-hrd
|value=string
|default="none"
|description=HRD-timing information
}}

=== Rate control ===
{{Option
|name=sout-x264-qp
|value=integer
|default=-1
|min=-1
|max=51
|description=Set QP
}}
{{Option
|name=sout-x264-crf
|value=integer
|default=23
|min=0
|max=51
|description=Quality-based [[VBR]]
}}
{{Option
|name=sout-x264-qpmin
|value=integer
|default=10
|min=0
|max=51
|description=Min QP
}}
{{Option
|name=sout-x264-qpmax
|value=integer
|default=51
|min=0
|max=51
|description=Max QP
}}
{{Option
|name=sout-x264-qpstep
|value=integer
|default=4
|min=0
|max=51
|description=Max QP step between [[frame]]s
}}
{{Option
|name=sout-x264-ratetol
|value=float
|default=1.0
|min=0
|max=100
|description=[[Average bitrate]] tolerance
}}
{{Option
|name=sout-x264-vbv-maxrate
|value=integer
|default=0
|description=Max local bitrate
}}
{{Option
|name=sout-x264-vbv-bufsize
|value=integer
|default=0
|description=VBV buffer
}}
{{Option
|name=sout-x264-vbv-init
|value=float
|default=0.9
|min=0
|max=1
|description=Initial VBV buffer occupancy
}}
{{Option
|name=sout-x264-ipratio
|value=float
|default=1.40
|min=1
|max=2
|description=QP factor between I and P
}}
{{Option
|name=sout-x264-pbratio
|value=float
|default=1.30
|min=1
|max=2
|description=QP factor between P and B
}}
{{Option
|name=sout-x264-chroma-qb-offset
|value=integer
|default=0
|description=QP difference between chroma and luma
}}
{{Option
|name=sout-x264-pass<span id="select_sout-x264-pass"></span>
|value=integer
|default=0
|select=[[#appendix_select_sout-x264-pass|{0,1,2,3}]]
|description=Multipass ratecontrol
}}
{{Option
|name=sout-x264-qcomp
|value=float
|default=0.60
|min=0
|max=1
|description=QP curve compression
}}
{{Option
|name=sout-x264-cplxblur
|value=float
|default=20.0
|description=Reduce fluctuations in QP
}}
{{Option
|name=sout-x264-qblur
|value=float
|default=0.5
|description=Reduce fluctuations in QP
}}
{{Option
|name=sout-x264-aq-mode<span id="select_sout-x264-aq-mode"></span>
|value=integer
|default=<var>X264_AQ_VARIANCE</var>
|select=[[#appendix_select_sout-x264-aq-mode|{0,1,2}]]
|description=Defines bitdistribution mode for AQ, default 1
}}
{{Option
|name=sout-x264-aq-strength
|value=float
|default=1.0
|description=Strength of AQ
}}

=== Analysis ===
{{Option
|name=sout-x264-partitions
|value=string
|default="normal"
|select={none,fast,normal,slow,all}
|description=Partitions to consider
}}
{{Option
|name=sout-x264-direct
|value=string
|default="spatial"
|select={none,spatial,temporal,auto}
|description=Direct MV prediction mode
}}
{{Option
|name=sout-x264-direct-8x8
|value=integer
|default=1
|min=-1
|max=1
|description=Direct prediction size
}}
{{Option
|name=sout-x264-weightb
|value=boolean
|default=enabled
|description=Weighted prediction for [[B-frame]]s
}}
{{Option
|name=sout-x264-weightp
|value=integer
|default=2
|min=0
|max=2
|description=Weighted prediction for [[P-frame]]s
}}
{{Option
|name=sout-x264-me
|value=string
|default="hex"
|select={dia,hex,umh,esa,tesa}
|description=Integer pixel motion estimation method
}}
{{Option
|name=sout-x264-merange
|value=integer
|default=16
|min=1
|max=64
|description=Maximum motion vector search range
}}
{{Option
|name=sout-x264-mvrange
|value=integer
|default=-1
|description=Maximum motion vector length
}}
{{Option
|name=sout-x264-mvrange-thread
|value=integer
|default=-1
|description=Minimum buffer space between threads
}}
{{Option
|name=sout-x264-subme
|value=integer
|default=7
|min=1
|max=9
|description=Subpixel motion estimation and partition decision quality
}}
{{Option
|name=sout-x264-mixed-refs
|value=boolean
|default=enabled
|description=Decide references on a per partition basis
}}
{{Option
|name=sout-x264-chroma-me
|value=boolean
|default=enabled
|description=Chroma in motion estimation
}}
{{Option
|name=sout-x264-8x8dct
|value=boolean
|default=enabled
|description=Adaptive spatial transform size
}}
{{Option
|name=sout-x264-trellis<span id="select_sout-x264-trellis"></span>
|value=integer
|default=1
|select=[[#appendix_select_sout-x264-trellis|{0,1,2}]]
|description=Trellis RD quantization: This requires CABAC
}}
{{Option
|name=sout-x264-lookahead
|value=integer
|default=40
|min=0
|max=60
|description=Framecount to use on frametype lookahead
}}
{{Option
|name=sout-x264-intra-refresh
|value=boolean
|default=disabled
|description=Use Periodic Intra Refresh
}}
{{Option
|name=sout-x264-mbtree
|value=boolean
|default=enabled
|description=Use mb-tree ratecontrol
}}
{{Option
|name=sout-x264-fast-pskip
|value=boolean
|default=enabled
|description=Early SKIP detection on [[P-frame]]s
}}
{{Option
|name=sout-x264-dct-decimate
|value=boolean
|default=enabled
|description=Coefficient thresholding on P-frames
}}
{{Option
|name=sout-x264-nr
|value=integer
|default=0
|min=0
|max=1000
|description=Noise reduction
}}
{{Option
|name=sout-x264-deadzone-inter
|value=integer
|default=21
|min=0
|max=32
|description=Inter luma quantization deadzone
}}
{{Option
|name=sout-x264-deadzone-intra
|value=integer
|default=11
|min=0
|max=32
|description=Intra luma quantization deadzone
}}

=== Input/Output ===
{{Option
|name=sout-x264-non-deterministic
|value=boolean
|default=disabled
|description=Non-deterministic optimizations when threaded
}}
{{Option
|name=sout-x264-asm
|value=boolean
|default=enabled
|description=CPU optimizations
}}
{{Option
|name=sout-x264-psnr
|value=boolean
|default=disabled
|description=PSNR computation
}}
{{Option
|name=sout-x264-ssim
|value=boolean
|default=disabled
|description=SSIM computation
}}
{{Option
|name=sout-x264-quiet
|value=boolean
|default=disabled
|description=Quiet mode
}}
{{Option
|name=sout-x264-sps-id
|value=integer
|default=0
|description=SPS and PPS id numbers
}}
{{Option
|name=sout-x264-aud
|value=boolean
|default=disabled
|description=Access unit delimiters
}}
{{Option
|name=sout-x264-verbose
|value=boolean
|default=disabled
|description=Statistics
}}
{{Option
|name=sout-x264-stats
|value=string
|default="x264_2pass.log"
|description=Filename for 2 pass stats file
}}
{{Option
|name=sout-x264-preset
|value=string
|default=NULL
|description=Default preset setting used
}}
{{Option
|name=sout-x264-tune
|value=string
|default=NULL
|description=Default tune setting used
}}
{{Option
|name=sout-x264-options
|value=string
|default=NULL
|description=[[x264]] advanced options, in the form <code>{opt=val,op2=val2}</code>
}}

=== Appendix ===
<span id="appendix_select_sout-x264-frame-packing"></span>
'''For the option <code>[[#select_sout-x264-frame-packing|--sout-x264-frame-packing]]</code>:'''
;-1: disabled
;0: checkerboard - pixels are alternatively from L and R
;1: column alternation - L and R are interlaced by column
;2: row alternation - L and R are interlaced by row
;3: side by side - L is on the left, R on the right
;4: top bottom - L is on top, R on bottom
;5: frame alternation - one view per frame

<span id="appendix_select_sout-x264-pass"></span>
'''For the option <code>[[#select_sout-x264-pass|--sout-x264-pass]]</code>:'''
;1: First pass, creates stats file
;2: Last pass, does not overwrite stats file
;3: <var>N</var><sup>th</sup> pass, overwrites stats file

<span id="appendix_select_sout-x264-aq-mode"></span>
'''For the option <code>[[#select_sout-x264-aq-mode|--sout-x264-aq-mode]]</code>:'''
;0: Disabled
;1: Current x264 default mode
;2: uses <code>log(var)&sup2;</code> instead of <code>log(var)</code> and attempts to adapt strength per frame

<span id="appendix_select_sout-x264-trellis"></span>
'''For the option <code>[[#select_sout-x264-trellis|--sout-x264-trellis]]</code>:'''
;0: disabled
;1: enabled only on the final encode of a MB
;2: enabled on all mode decisions

== Source code ==
* {{VLCSourceFile|modules/codec/x264.c}}

{{Documentation}}