mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2024-12-02 03:06:28 +02:00
162 lines
4.6 KiB
Plaintext
162 lines
4.6 KiB
Plaintext
@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.
|
|
|
|
@section libcelt
|
|
|
|
libcelt decoder wrapper.
|
|
|
|
libcelt allows libavcodec to decode the Xiph CELT ultra-low delay audio codec.
|
|
Requires the presence of the libcelt headers and library during configuration.
|
|
You need to explicitly configure the build with @code{--enable-libcelt}.
|
|
|
|
@section libgsm
|
|
|
|
libgsm decoder wrapper.
|
|
|
|
libgsm allows libavcodec to decode the GSM full rate audio codec. Requires
|
|
the presence of the libgsm headers and library during configuration. You need
|
|
to explicitly configure the build with @code{--enable-libgsm}.
|
|
|
|
This decoder supports both the ordinary GSM and the Microsoft variant.
|
|
|
|
@section libilbc
|
|
|
|
libilbc decoder wrapper.
|
|
|
|
libilbc allows libavcodec to decode the Internet Low Bitrate Codec (iLBC)
|
|
audio codec. Requires the presence of the libilbc headers and library during
|
|
configuration. You need to explicitly configure the build with
|
|
@code{--enable-libilbc}.
|
|
|
|
@subsection Options
|
|
|
|
The following option is supported by the libilbc wrapper.
|
|
|
|
@table @option
|
|
@item enhance
|
|
|
|
Enable the enhancement of the decoded audio when set to 1. The default
|
|
value is 0 (disabled).
|
|
|
|
@end table
|
|
|
|
@section libopencore-amrnb
|
|
|
|
libopencore-amrnb decoder wrapper.
|
|
|
|
libopencore-amrnb allows libavcodec to decode the Adaptive Multi-Rate
|
|
Narrowband audio codec. Using it requires the presence of the
|
|
libopencore-amrnb headers and library during configuration. You need to
|
|
explicitly configure the build with @code{--enable-libopencore-amrnb}.
|
|
|
|
An FFmpeg native decoder for AMR-NB exists, so users can decode AMR-NB
|
|
without this library.
|
|
|
|
@section libopencore-amrwb
|
|
|
|
libopencore-amrwb decoder wrapper.
|
|
|
|
libopencore-amrwb allows libavcodec to decode the Adaptive Multi-Rate
|
|
Wideband audio codec. Using it requires the presence of the
|
|
libopencore-amrwb headers and library during configuration. You need to
|
|
explicitly configure the build with @code{--enable-libopencore-amrwb}.
|
|
|
|
An FFmpeg native decoder for AMR-WB exists, so users can decode AMR-WB
|
|
without this library.
|
|
|
|
@section libopus
|
|
|
|
libopus decoder wrapper.
|
|
|
|
libopus allows libavcodec to decode the Opus Interactive Audio Codec.
|
|
Requires the presence of the libopus headers and library during
|
|
configuration. You need to explicitly configure the build with
|
|
@code{--enable-libopus}.
|
|
|
|
@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
|