mpv/DOCS/encoding.rst

General usage
=============

::

  mpv infile --o=outfile [--of=outfileformat] [--ofopts=formatoptions] [--orawts] \
    [(any other mpv options)] \
    --ovc=outvideocodec [--ovcopts=outvideocodecoptions] \
    --oac=outaudiocodec [--oacopts=outaudiocodecoptions]

Help for these options is provided if giving help as parameter, as in::

  mpv --ovc=help

The suboptions of these generally are identical to ffmpeg's (as option parsing
is simply delegated to ffmpeg). The option --ocopyts enables copying timestamps
from the source as-is, instead of fixing them to match audio playback time
(note: this doesn't work with all output container formats); --orawts even turns
off discontinuity fixing.

Note that if neither --ofps nor --oautofps is specified, VFR encoding is assumed
and the time base is 24000fps. --oautofps sets --ofps to a guessed fps number
from the input video. Note that not all codecs and not all formats support VFR
encoding, and some which do have bugs when a target bitrate is specified - use
--ofps or --oautofps to force CFR encoding in these cases.

Of course, the options can be stored in a profile, like this .config/mpv/mpv.conf
section::

  [myencprofile]
  vf-add = scale=480:-2
  ovc = libx264
  ovcopts-add = preset=medium
  ovcopts-add = tune=fastdecode
  ovcopts-add = crf=23
  ovcopts-add = maxrate=1500k
  ovcopts-add = bufsize=1000k
  ovcopts-add = rc_init_occupancy=900k
  ovcopts-add = refs=2
  ovcopts-add = profile=baseline
  oac = aac
  oacopts-add = b=96k

It's also possible to define default encoding options by putting them into
the section named ``[encoding]``. (This behavior changed after mpv 0.3.x. In
mpv 0.3.x, config options in the default section / no section were applied
to encoding. This is not the case anymore.)

One can then encode using this profile using the command::

  mpv infile --o=outfile.mp4 --profile=myencprofile

Some example profiles are provided in a file
etc/encoding-profiles.conf; as for this, see below.


Encoding examples
=================

These are some examples of encoding targets this code has been used and tested
for.

Typical MPEG-4 Part 2 ("ASP", "DivX") encoding, AVI container::

  mpv infile --o=outfile.avi \
    --vf=fps=25 \
    --ovc=mpeg4 --ovcopts=qscale=4 \
    --oac=libmp3lame --oacopts=b=128k

Note: AVI does not support variable frame rate, so the fps filter must be used.
The frame rate should ideally match the input (25 for PAL, 24000/1001 or
30000/1001 for NTSC)

Typical MPEG-4 Part 10 ("AVC", "H.264") encoding, Matroska (MKV) container::

  mpv infile --o=outfile.mkv \
    --ovc=libx264 --ovcopts=preset=medium,crf=23,profile=baseline \
    --oac=libopus --oacopts=qscale=3

Typical MPEG-4 Part 10 ("AVC", "H.264") encoding, MPEG-4 (MP4) container::

  mpv infile --o=outfile.mp4 \
    --ovc=libx264 --ovcopts=preset=medium,crf=23,profile=baseline \
    --oac=aac --oacopts=b=128k

Typical VP8 encoding, WebM (restricted Matroska) container::

  mpv infile -o outfile.mkv \
    --of=webm \
    --ovc=libvpx --ovcopts=qmin=6,b=1000000k \
    --oac=libopus --oacopts=qscale=3


Device targets
==============

As the options for various devices can get complex, profiles can be used.

An example profile file for encoding is provided in
etc/encoding-profiles.conf in the source tree. This file is installed and loaded
by default. If you want to modify it, you can replace and it with your own copy
by doing::

  mkdir -p ~/.mpv
  cp /etc/mpv/encoding-profiles.conf ~/.mpv/encoding-profiles.conf

Keep in mind that the default profile is the playback one. If you want to add
options that apply only in encoding mode, put them into a ``[encoding]``
section.

Refer to the top of that file for more comments - in a nutshell, the following
options are added by it::

  --profile=enc-to-dvdpal      # DVD-Video PAL, use dvdauthor -v pal+4:3 -a ac3+en
  --profile=enc-to-dvdntsc     # DVD-Video NTSC, use dvdauthor -v ntsc+4:3 -a ac3+en
  --profile=enc-to-bb-9000     # MP4 for Blackberry Bold 9000
  --profile=enc-to-nok-6300    # 3GP for Nokia 6300
  --profile=enc-to-psp         # MP4 for PlayStation Portable
  --profile=enc-to-iphone      # MP4 for iPhone
  --profile=enc-to-iphone-4    # MP4 for iPhone 4 (double res)
  --profile=enc-to-iphone-5    # MP4 for iPhone 5 (even larger res)

You can encode using these with a command line like::

  mpv infile --o=outfile.mp4 --profile=enc-to-bb-9000

Of course, you are free to override options set by these profiles by specifying
them after the -profile option.


What works
==========

* Encoding at variable frame rate (default)
* Encoding at constant frame rate using --vf=fps=RATE
* 2-pass encoding (specify flags=+pass1 in the first pass's --ovcopts, specify
  flags=+pass2 in the second pass)
* Hardcoding subtitles using vobsub, ass or srt subtitle rendering (just
  configure mpv for the subtitles as usual)
* Hardcoding any other mpv OSD (e.g. time codes, using --osdlevel=3 and
  --vf=expand=::::1)
* Encoding directly from a DVD, network stream, webcam, or any other source
  mpv supports
* Using x264 presets/tunings/profiles (by using profile=, tune=, preset= in the
  --ovcopts)
* Deinterlacing/Inverse Telecine with any of mpv's filters for that
* Audio file converting: mpv --o=outfile.m4a infile.flac --no-video
  --oac=aac --oacopts=b=320k

What does not work yet
======================

* 3-pass encoding (ensuring constant total size and bitrate constraints while
  having VBR audio; mencoder calls this "frameno")
* Direct stream copy