ghostess(1) graphical DSSI plugin host


ghostess [-debug level] [-hostname hostname] [-projdir projdir] [-uuid uuid] [-noauto] [-f cfgfile] [-n] [-chan c] [-conf k v] [-prog b p] [-port p f] soname[:label] [...]


ghostess is a DSSI host that listens for MIDI events, delivers them to DSSI synth plugins, and outputs the resulting audio via JACK. ghostess also supports DSSI plugins having audio inputs (effects), LADSPA plugins, and the use of DSSI-style user interfaces with LADSPA plugins. ghostess can host up to 32 plugin instances at one time.

Depending on the compile-time configuration, ghostess will receive MIDI events from ALSA, JACK MIDI, or CoreMIDI. Unless otherwise specified by the -chan option, each plugin instance is sequentially assigned a MIDI channel, wrapping from 15 (zero-based) back to 0 when necessary. Unless -noauto is specified, plugin inputs and outputs are connected sequentially to the available JACK physical input and output ports, respectively, wrapping back to the first port whenever the available ports are exhausted.

At startup, ghostess presents a simple GTK+ user interface. Each plugin instance is represented in a frame, labeled with the plugin name, and containing a MIDI activity indicator and a 'UI' button. Left-clicking the 'UI' button will start or hide the plugin's user interface (UI). Right-clicking the 'UI' button will allowing starting, hiding, showing, or terminating the plugin's UI.

The 'Save Configuration...' option of ghostess's 'File' menu allows saving the current configuration of all plugins to a file. Basically, the file is just a Bourne shell script that can be used to recreate the configuration.

ghostess comes with a minimal universal DSSI GUI, ghostess_universal_gui, that can be used with any DSSI or LADSPA plugin. It does not read RDF files or instantiate the plugin, so it's not as full-featured as a universal GUI could be, but it does allow for adjusting DSSI/LADSPA ports, selecting bank and program (for plugins with select_program()), and sending test notes (for plugins with any of the run_synth() functions). If ghostess cannot find a UI for a plugin, and the universal GUI is in the PATH, ghostess will launch it.


The following global options are available:
-debug level
Sets bitfield flags which determine which debugging information is printed. The default level of 1 shows errors only, 0 shows nothing, and -1 shows everything. See ghostess.h for details.
-hostname hostname
Sets hostname as the name ghostess uses for itself, for JACK and ALSA clients and GUI window titles. If a JACK port cannot be created with that name, the PID is appended.
-projdir projdir
Sets the project directory passed to both plugins and UIs to projdir. The default is none.
-uuid uuid
Sets uuid as the UUID used for JACK session management. There is probably no reason to use this outside of a managed session.
Disables automatic connection of plugin outputs to JACK physical outputs.
-f cfgfile
Additional configuration will be read from cfgfile, in the same format as command line options.

For specifying plugin instances, ghostess uses a '[-repetition-count] [options] soname[:label]' format, which may be repeated for multiple instances. The plugin-specific options are:

Specifies the repitition count, or number of instances, of the following plugin to create, where n is an integer between 1 (the default) and 32.
-chan c
Sets the initial MIDI channel for the following plugin instance to c. Channels are numbered 0 to 15. If the repetition count is more than one, instances are given sequential channels beginning with c and wrapping from 15 to 0. The default is for all instances' MIDI channels to be sequentially numbered, starting from 0.
-conf k v
Sets configure item key k and value v for the following instance. May be repeated for multiple keys.
-prog b p
Sets the program change bank b and program p for the following plugin (numbered from 0).
-port p f
Sets the value of port p to floating point number f for the following plugin. May be repeated for different ports.
The name of the DSSI or LADSPA plugin library to load, including the '.so' suffix. soname may be an absolute path to the library file, or just the filename itself, in which case the DSSI search path is searched (see ENVIRONMENT below).
The label of the DSSI or LADSPA plugin to load from the library soname. If this is omitted, the first plugin in the library is used.


ghostess will search for plugin shared libraries in the directories specified by the environment variable DSSI_PATH, which is a colon-separated list of directories. If DSSI_PATH is not set, a default search path of /usr/lib/dssi, /usr/local/lib/dssi, and (assuming the environment variable HOME is set,) $HOME/.dssi is used. Note that while ghostess may be used to host LADSPA plugins, the environment variable LADSPA_PATH is not used to search for them.


Assuming DSSI_PATH is correctly set, the command:

$ ghostess

will start a single instance of the plugin hexter, listening on MIDI channel 0, with its output connected to the first JACK physical output port.

The command:

$ ghostess -noauto -chan 2 -chan 2

will start two instances of Xsynth-DSSI, both listening on MIDI channel 2, but will not automatically connect the plugin outputs to JACK output ports.

The command:

$ ghostess -debug -1 -hostname fuzzy -projdir /tmp/proj -2 -conf load mypatches -prog 0 4 -port 7 0.45

will start two instances of the 'fuzz' plugin within the library, using /tmp/proj as the project directory, pass configure key 'load' with value 'mypatches' to both instances, set bank 0 and program 4, and set port 7 to 0.45. Assuming it is some sort of effect, the plugins' inputs and outputs will be automatically connected to the first JACK physical inputs and outputs. Full debugging information will be printed, and fuzzy will be used as the JACK client name.


ghostess was written by Sean Bolton, who mercilessly mangled code originally written by Chris Cannam and Steve Harris. This manual page was adapted by Sean Bolton from the jack-dssi-host manual page originally by Mark Hymers.