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Commit d235d240 authored by Michael Niedermayer's avatar Michael Niedermayer
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Merge commit 'ded3673d' 

* commit 'ded3673d':
  doc: document libx264 options and mappings
  libx264: introduce -x264-params private option

Conflicts:
	doc/encoders.texi
Merged-by: 's avatarMichael Niedermayer <michaelni@gmx.at>
parents e7e14bc6 ded3673d
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doc/encoders.texi
View file @ d235d240
......@@ -581,40 +581,175 @@ For more information about libvpx see:
@section libx264
H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 format supported through
libx264.
x264 H.264/MPEG-4 AVC encoder wrapper
Requires the presence of the libx264 headers and library during
configuration. You need to explicitly configure the build with
@code{--enable-libx264}.
@subsection Options
x264 supports an impressive number of features, including 8x8 and 4x4 adaptive
spatial transform, adaptive B-frame placement, CAVLC/CABAC entropy coding,
interlacing (MBAFF), lossless mode, psy optimizations for detail retention
(adaptive quantization, psy-RD, psy-trellis).
The FFmpeg wrapper provides a mapping for most of them using global options
that match those of the encoders and provides private options for the unique
encoder options. Additionally an expert override is provided to directly pass
a list of key=value tuples as accepted by x264_param_parse.
@subsection Option Mapping
The following options are supported by the x264 wrapper, the x264-equivalent
options follow the FFmpeg ones.
@multitable @columnfractions .2 .2
@item b @tab bitrate
FFmpeg @code{b} option is expressed in bits/s, x264 @code{bitrate} in kilobits/s.
@item bf @tab bframes
Maximum number of B-frames.
@item g @tab keyint
Maximum GOP size.
@item qmin @tab qpmin
@item qmax @tab qpmax
@item qdiff @tab qpstep
@item qblur @tab qblur
@item qcomp @tab qcomp
@item refs @tab ref
@item sc_threshold @tab scenecut
@item trellis @tab trellis
@item nr @tab nr
Noise reduction.
@item me_range @tab merange
@item me_method @tab me
@item subq @tab subme
@item b_strategy @tab b-adapt
@item keyint_min @tab keyint-min
@item coder @tab cabac
Set coder to @code{ac} to use CABAC.
@item cmp @tab chroma-me
Set to @code{chroma} to use chroma motion estimation.
@item threads @tab threads
@item thread_type @tab sliced_threads
Set to @code{slice} to use sliced threading instead of frame threading.
@item flags -cgop @tab open-gop
Set @code{-cgop} to use recovery points to close GOPs.
@item rc_init_occupancy @tab vbv-init
Initial buffer occupancy.
@end multitable
@subsection Private Options
@table @option
@item -preset @var{string}
Set the encoding preset (cf. x264 --fullhelp).
@item -tune @var{string}
Tune the encoding params (cf. x264 --fullhelp).
@item -profile @var{string}
Set profile restrictions (cf. x264 --fullhelp).
@item -fastfirstpass @var{integer}
Use fast settings when encoding first pass.
@item -crf @var{float}
Select the quality for constant quality mode.
@item -crf_max @var{float}
In CRF mode, prevents VBV from lowering quality beyond this point.
@item -qp @var{integer}
Constant quantization parameter rate control method.
@item -aq-mode @var{integer}
AQ method
Possible values:
@table @samp
@item none
@item variance
Variance AQ (complexity mask).
@item autovariance
Auto-variance AQ (experimental).
@end table
@item -aq-strength @var{float}
AQ strength, reduces blocking and blurring in flat and textured areas.
@item -psy @var{integer}
Use psychovisual optimizations.
@item -psy-rd @var{string}
Strength of psychovisual optimization, in <psy-rd>:<psy-trellis> format.
@item -rc-lookahead @var{integer}
Number of frames to look ahead for frametype and ratecontrol.
@item -weightb @var{integer}
Weighted prediction for B-frames.
@item -weightp @var{integer}
Weighted prediction analysis method.
Possible values:
@table @samp
@item none
@item simple
@item smart
@item preset @var{preset_name}
Set the encoding preset.
@item tune @var{tune_name}
Tune the encoding params.
@end table
@item -ssim @var{integer}
Calculate and print SSIM stats.
@item -intra-refresh @var{integer}
Use Periodic Intra Refresh instead of IDR frames.
@item -b-bias @var{integer}
Influences how often B-frames are used.
@item -b-pyramid @var{integer}
Keep some B-frames as references.
Possible values:
@table @samp
@item none
@item strict
Strictly hierarchical pyramid.
@item normal
Non-strict (not Blu-ray compatible).
@end table
@item -mixed-refs @var{integer}
One reference per partition, as opposed to one reference per macroblock.
@item -8x8dct @var{integer}
High profile 8x8 transform.
@item -fast-pskip @var{integer}
@item -aud @var{integer}
Use access unit delimiters.
@item -mbtree @var{integer}
Use macroblock tree ratecontrol.
@item -deblock @var{string}
Loop filter parameters, in <alpha:beta> form.
@item -cplxblur @var{float}
Reduce fluctuations in QP (before curve compression).
@item -partitions @var{string}
A comma-separated list of partitions to consider, possible values: p8x8, p4x4, b8x8, i8x8, i4x4, none, all.
@item -direct-pred @var{integer}
Direct MV prediction mode
Possible values:
@table @samp
@item none
@item spatial
@item temporal
@item auto
@item fastfirstpass @var{bool}
Use fast settings when encoding first pass, default value is 1.
@end table
@item -slice-max-size @var{integer}
Limit the size of each slice in bytes.
@item -stats @var{string}
Filename for 2 pass stats.
@item -nal-hrd @var{integer}
Signal HRD information (requires vbv-bufsize; cbr not allowed in .mp4).
@item profile @var{profile_name}
Set profile restrictions.
Possible values:
@table @samp
@item none
@item level @var{level}
Specify level (as defined by Annex A).
Deprecated in favor of @var{x264opts}.
@item vbr
@item passlogfile @var{filename}
Specify filename for 2 pass stats.
Deprecated in favor of @var{x264opts} (see @var{stats} libx264 option).
@item cbr
@item wpredp @var{wpred_type}
Specify Weighted prediction for P-frames.
Deprecated in favor of @var{x264opts} (see @var{weightp} libx264 option).
@end table
@item x264opts @var{options}
Allow to set any x264 option, see @code{x264 --fullhelp} for a list.
......@@ -623,7 +758,6 @@ Allow to set any x264 option, see @code{x264 --fullhelp} for a list.
":". In @var{filter} and @var{psy-rd} options that use ":" as a separator
themselves, use "," instead. They accept it as well since long ago but this
is kept undocumented for some reason.
@end table
For example to specify libx264 encoding options with @command{ffmpeg}:
@example
......@@ -633,4 +767,14 @@ ffmpeg -i foo.mpg -vcodec libx264 -x264opts keyint=123:min-keyint=20 -an out.mkv
For more information about libx264 and the supported options see:
@url{http://www.videolan.org/developers/x264.html}
@item -x264-params @var{string}
Override the x264 configuration using a :-separated list of key=value parameters.
@example
-x264-params level=30:bframes=0:weightp=0:cabac=0:ref=1:vbv-maxrate=768:vbv-bufsize=2000:analyse=all:me=umh:no-fast-pskip=1:subq=6:8x8dct=0:trellis=0
@end example
@end table
Encoding avpresets for common usages are provided so they can be used with the
general presets system (e.g. passing the @code{-pre} option).
@c man end VIDEO ENCODERS
libavcodec/libx264.c
View file @ d235d240
......@@ -73,6 +73,7 @@ typedef struct X264Context {
int slice_max_size;
char *stats;
int nal_hrd;
char *x264_params;
} X264Context;
static void X264_log(void *p, int level, const char *fmt, va_list args)
......@@ -522,6 +523,22 @@ static av_cold int X264_init(AVCodecContext *avctx)
if (avctx->flags & CODEC_FLAG_GLOBAL_HEADER)
x4->params.b_repeat_headers = 0;
if (x4->x264_params) {
AVDictionary *dict = NULL;
AVDictionaryEntry *en = NULL;
if (!av_dict_parse_string(&dict, x4->x264_params, "=", ":", 0)) {
while ((en = av_dict_get(dict, "", en, AV_DICT_IGNORE_SUFFIX))) {
if (x264_param_parse(&x4->params, en->key, en->value) < 0)
av_log(avctx, AV_LOG_WARNING,
"Error parsing option '%s = %s'.\n",
en->key, en->value);
}
av_dict_free(&dict);
}
}
// update AVCodecContext with x264 parameters
avctx->has_b_frames = x4->params.i_bframe ?
x4->params.i_bframe_pyramid ? 2 : 1 : 0;
......@@ -653,6 +670,7 @@ static const AVOption options[] = {
{ "none", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = X264_NAL_HRD_NONE}, INT_MIN, INT_MAX, VE, "nal-hrd" },
{ "vbr", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = X264_NAL_HRD_VBR}, INT_MIN, INT_MAX, VE, "nal-hrd" },
{ "cbr", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = X264_NAL_HRD_CBR}, INT_MIN, INT_MAX, VE, "nal-hrd" },
{ "x264-params", "Override the x264 configuration using a :-separated list of key=value parameters", OFFSET(x264_params), AV_OPT_TYPE_STRING, { 0 }, 0, 0, VE },
{ NULL },
};
......
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