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- @chapter Decoders
- @c man begin DECODERS
-
- Decoders are configured elements in Libav which allow the decoding of
- multimedia streams.
-
- When you configure your Libav 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{-decoders} of the av* tools will display the list of
- enabled decoders.
-
- @c man end DECODERS
-
- @chapter Audio Decoders
- @c man begin AUDIO DECODERS
-
- A description of some of the currently available audio decoders
- follows.
-
- @section ac3
-
- AC-3 audio decoder.
-
- This decoder implements part of ATSC A/52:2010 and ETSI TS 102 366, as well as
- the undocumented RealAudio 3 (a.k.a. dnet).
-
- @subsection AC-3 Decoder Options
-
- @table @option
-
- @item -drc_scale @var{value}
- Dynamic Range Scale Factor. The factor to apply to dynamic range values
- from the AC-3 stream. This factor is applied exponentially.
- There are 3 notable scale factor ranges:
- @table @option
- @item drc_scale == 0
- DRC disabled. Produces full range audio.
- @item 0 < drc_scale <= 1
- DRC enabled. Applies a fraction of the stream DRC value.
- Audio reproduction is between full range and full compression.
- @item drc_scale > 1
- DRC enabled. Applies drc_scale asymmetrically.
- Loud sounds are fully compressed. Soft sounds are enhanced.
- @end table
-
- @end table
-
- @c man end AUDIO DECODERS
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