mirror of https://github.com/mpv-player/mpv
General note about filtering from Rich's encoding guide
git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@16088 b3059339-0415-0410-9bf9-f77b7e298cf2
This commit is contained in:
parent
97e333bf0d
commit
2d9385aebc
|
@ -1085,6 +1085,49 @@
|
|||
<sect2 id="menc-feat-dvd-mpeg4-filtering">
|
||||
<title>Filtering</title>
|
||||
|
||||
<para>
|
||||
Learning how to use <application>MEncoder</application>'s video filters
|
||||
is essential to producing good encodes.
|
||||
All video processing is performed through the filters -- cropping,
|
||||
scaling, color adjustment, noise removal, sharpening, deinterlacing,
|
||||
telecine, inverse telecine, and deblocking, just to name a few.
|
||||
Along with the vast number of supported input formats, the variety of
|
||||
filters available in <application>MEncoder</application> is one of its
|
||||
main advantages over other similar programs.
|
||||
</para>
|
||||
|
||||
<para>
|
||||
Filters are loaded in a chain using the -vf option:
|
||||
|
||||
<screen>-vf filter1=options,filter2=options,...</screen>
|
||||
|
||||
Most filters take several numeric options separated by colons, but
|
||||
the syntax for options varies from filter to filter, so read the man
|
||||
page for details on the filters you wish to use.
|
||||
</para>
|
||||
|
||||
<para>
|
||||
Filters operate on the video in the order they are loaded.
|
||||
For example, the following chain:
|
||||
|
||||
<screen>-vf crop=688:464:12:4,scale=640:464</screen>
|
||||
|
||||
will first crop the 688x464 region of the picture with upper-left
|
||||
corner at (12,4), and then scale the result down to 640x464.
|
||||
</para>
|
||||
|
||||
<para>
|
||||
Certain filters need to be loaded at or near the beginning of the
|
||||
filter chain, in order to take advantage of information from the
|
||||
video decoder that will be lost or invalidated by other filters.
|
||||
The principal examples are <option>pp</option> (postprocessing, only
|
||||
when it is performing deblock or dering operations),
|
||||
<option>spp</option> (another postprocessor to remove MPEG artifacts),
|
||||
<option>pullup</option> (inverse telecine), and
|
||||
<option>softpulldown</option> (for converting soft telecine to hard
|
||||
telecine).
|
||||
</para>
|
||||
|
||||
<para>
|
||||
In general, you want to do as little filtering as possible to the movie
|
||||
in order to remain close to the original DVD source. Cropping is often
|
||||
|
|
Loading…
Reference in New Issue