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.. | ||
calf-lv2-port-groups.patch | ||
gstlv2.c | ||
gstlv2.h | ||
gstlv2filter.c | ||
gstlv2source.c | ||
gstlv2utils.c | ||
gstlv2utils.h | ||
meson.build | ||
README | ||
swh-lv2-port-groups.patch |
Gst-LV2 Quickstart Dependencies: Lilv 0.6.6 <http://drobilla.net/software/lilv/> Features: The plugin wrapper support the following plugin features: http://lv2plug.in/ns/lv2core http://lv2plug.in/ns/ext/event http://lv2plug.in/ns/ext/port-groups and these host features: http://lv2plug.in/ns/ext/log http://lv2plug.in/ns/ext/urid Example Pipeline: Requires swh-lv2 <http://plugin.org.uk/releases/> gst-launch-1.0 -v filesrc location=/usr/share/sounds/login.wav ! wavparse ! audioconvert ! plugin-org-uk-swh-plugins-djFlanger ! audioconvert ! autoaudiosink (A longer wav will be a better example) gst-launch-1.0 plugin-org-uk-swh-plugins-analogueOsc num-buffers=100 wave=1 ! wavenc ! filesink location="/tmp/lv2.wav" Requires calf <http://calf.sourceforge.net/> GST_DEBUG="*:2,lv2:5" gst-launch-1.0 calf-sourceforge-net-plugins-Monosynth event-in="C-3" ! autoaudiosink gst-launch-1.0 calf-sourceforge-net-plugins-Monosynth event-in="C-3" name=ms ! autoaudiosink ms. ! fakesink gst-launch-1.0 calf-sourceforge-net-plugins-Organ event-in="C-3" name=s ! interleave name=i ! autoaudiosink s. ! i. TODO * make filters gap-aware * report latency lilv_plugin_has_latency(), lilv_plugin_get_latency_port_index() * support more host features GST_DEBUG="lv2:4" GST_DEBUG_FILE=/tmp/gst.log gst-inspect lv2 grep -o "needs host feature: .*$" /tmp/gst.log | sort | uniq -c | sort -n * make source elements useful Most source elements use Atom port where they accept midi events. Since it is full fledged midi, we should only ever use channel-0 and instead use multiple instances 1) We could expose those as "audio/x-midi-event" sink pads, but then those are not sources anymore. 2) We could expose those as properties using a new type like GST_FOURCC. If we ignore "System Exclusive" messages, all other midi messages are 1-3 bytes. We stuff the bytes right to left. E.g: the lowest byte is the status byte 3) We could use the GstBtNote enum + the toneconversion classes https://www.midi.org/specifications/item/table-1-summary-of-midi-message Open questions: - with one property, we can't handle polyphony - we can't query lv2 plugins for their polyphony :/ If lv2 gets a polyphony extension it would be a single non-negative integer: 0: unbound, 1 monophonic, > 1 N-polyphonic I've checked a few synths and they all have an upper limit. Still the way voices work in trackers is not the same as they work in synths - e.g. in a tracker one can play a note twice Or we just play them monophonic and try to implement a polychildbin. The bin takes a GstElement to be used as a voice. For each new voice it would create a new instance and it uses a built-in mixer. Downside is that all properties would be per voice. * example sources: http://svn.drobilla.net/lad/trunk/lilv/utils/lv2info.c http://svn.drobilla.net/lad/trunk/jalv/src/jalv.c