@chapter Decoders
@c man begin DECODERS

Decoders are configured elements in FFmpeg which allow the decoding of
multimedia streams.

When you configure your FFmpeg build, all the supported native decoders
are enabled by default. Decoders requiring an external library must be enabled
manually via the corresponding @code{--enable-lib} option. You can list all
available decoders using the configure option @code{--list-decoders}.

You can disable all the decoders with the configure option
@code{--disable-decoders} and selectively enable / disable single decoders
with the options @code{--enable-decoder=@var{DECODER}} /
@code{--disable-decoder=@var{DECODER}}.

The option @code{-codecs} of the ff* tools will display the list of
enabled decoders.

@c man end DECODERS

@chapter Video Decoders
@c man begin VIDEO DECODERS

A description of some of the currently available video decoders
follows.

@section rawvideo

Raw video decoder.

This decoder decodes rawvideo streams.

@subsection Options

@table @option
@item top @var{top_field_first}
Specify the assumed field type of the input video.
@table @option
@item -1
the video is assumed to be progressive (default)
@item 0
bottom-field-first is assumed
@item 1
top-field-first is assumed
@end table

@end table

@c man end VIDEO DECODERS

@chapter Audio Decoders
@c man begin AUDIO DECODERS

@section ffwavesynth

Internal wave synthetizer.

This decoder generates wave patterns according to predefined sequences. Its
use is purely internal and the format of the data it accepts is not publicly
documented.

@c man end AUDIO DECODERS

@chapter Subtitles Decoders
@c man begin SUBTILES DECODERS

@section dvdsub

This codec decodes the bitmap subtitles used in DVDs; the same subtitles can
also be found in VobSub file pairs and in some Matroska files.

@subsection Options

@table @option
@item palette
Specify the global palette used by the bitmaps. When stored in VobSub, the
palette is normally specified in the index file; in Matroska, the palette is
stored in the codec extra-data in the same format as in VobSub. In DVDs, the
palette is stored in the IFO file, and therefore not available when reading
from dumped VOB files.

The format for this option is a string containing 16 24-bits hexadecimal
numbers (without 0x prefix) separated by comas, for example @code{0d00ee,
ee450d, 101010, eaeaea, 0ce60b, ec14ed, ebff0b, 0d617a, 7b7b7b, d1d1d1,
7b2a0e, 0d950c, 0f007b, cf0dec, cfa80c, 7c127b}.
@end table

@c man end SUBTILES DECODERS