mirror of
https://github.com/ElvishArtisan/rivendell.git
synced 2025-04-24 09:28:54 +02:00
94 lines
3.9 KiB
Plaintext
94 lines
3.9 KiB
Plaintext
File Exporting and Encoders in Rivendell
|
|
|
|
Rivendell has the capability to export audio in many different formats using
|
|
several different modules (RDLibrary, RDCatch and RDCastManager). To
|
|
accomplish this, Rivendell uses audio *encoder* objects, each of which enable
|
|
one or more particular 'export formats'. A list of all
|
|
recognized export formats for each host can be found by looking in
|
|
RDAdmin->ManageHosts->AudioResources, under 'Supported Export Formats'.
|
|
|
|
Encoders in Rivendell come in two different basic types, "built-in", and
|
|
"custom". Each type is discussed separately below.
|
|
|
|
|
|
BUILT-IN ENCODERS
|
|
Some built-in encoders are enabled automatically as part of the basic
|
|
Rivendell installation process, while others require one or more external
|
|
library packages in order to be recognized and used. The following chart
|
|
shows the dependencies:
|
|
|
|
FORMAT REQUIRED PACKAGE(S) AVAILABLE AT
|
|
-------------------------------------------------------------------------
|
|
Linear PCM16 [included]
|
|
MPEG 1,2 Layer 2 [included]
|
|
MPEG 1,2 Layer 3 Lame http://lame.sourceforge.net
|
|
FLAC Flac http://flac.sourceforge.net
|
|
OggVorbis LibOgg, LibVorbis http://www.vorbis.com
|
|
|
|
|
|
CUSTOM ENCODERS
|
|
It is possible to configure a Rivendell host to export audio in a format not
|
|
supported by one of the built-in encoders by configuring a 'custom' encoder.
|
|
Generally, all that is needed is an encoder program that can be invoked from
|
|
the Linux command-line. The configuration is done in
|
|
RDAdmin->ManageHosts->CustomEncoders. Each encoder needs the following
|
|
information:
|
|
|
|
NAME
|
|
A unique-per-host name for the encoder.
|
|
|
|
DEFAULT EXTENSION
|
|
A typically two- or three-letter long file extension to associate with this
|
|
encoder.
|
|
|
|
COMMAND LINE
|
|
The command line that Rivendell should invoke to encode a file. When invoked,
|
|
Rivendell will pipe the source audio data into standard input of the program
|
|
shown here, using sixteen-bit little-endian format with no headers (so-called
|
|
'raw' mode) and with channelization and sample rate as indicated in the
|
|
configuration for the specific export being executed. The following
|
|
wildcard characters can be used to pass parameters from the specfic export
|
|
configuration:
|
|
|
|
%f - Full destination path/name.
|
|
%c - Number of channels
|
|
%r - Sample rate, in samples/sec
|
|
%b - Bitrate, in bits/sec
|
|
|
|
ALLOWABLE PARAMETERS
|
|
Finally, each encoder can be provided with a list of zero or more 'allowed'
|
|
values for Channel, Sample Rate and Bit Rate. Rivendell will use these values
|
|
(along with the 'NAME' value, see above) to populate the approriate controls
|
|
in the Edit Export Settings dialog. If no values are configured for a
|
|
particular parameter, then the correponding control in the dialog will be
|
|
shown as disabled ("greyed-out"), in which case it is assumed that the encoder
|
|
being invoked either does not need the parameter or has had it hard-coded in
|
|
the configured command line.
|
|
|
|
|
|
EXAMPLE
|
|
As an example, let's set up a custom encoder to produce 'Flash' encoded audio
|
|
files using the FFmpeg multimedia transcoder (http://ffmpeg.mplayerhq.hu/) and
|
|
the Freeware Advanced Audio Coder (http://sourceforge.net/projects/faac/).
|
|
After installing these packages and verifying that Flash files can be
|
|
successfully generated from the command line, we go into
|
|
RDAdmin->ManageHosts->CustomEncoders, click the 'Add' button and fill out the
|
|
name:
|
|
|
|
New Encoder Name: Flash AAC
|
|
|
|
Click 'Ok', and the Edit Encoder dialog will open. Fill out the parameters
|
|
as follows:
|
|
|
|
Default Extension: flv
|
|
Command Line: ffmpeg -y -vn -f s16le -ac %c -ar %r -i - -vn -f flv -acodec libfaac -ac %c -ar %r -ab %b %f
|
|
Allow Channels: 1,2
|
|
Allow Sample Rates: 22050,44100
|
|
Allow Bit Rates: 8,16
|
|
|
|
Note that the bit rates here are specified in kbps!
|
|
|
|
Click 'OK' to save, then go to RDAdmin->ManageHosts->AudioResources. You
|
|
should now see a 'Flash AAC [Custom]' entry in the 'SUPPORTED EXPORT FORMATS'
|
|
list.
|