+#!/usr/bin/env python3
+#
+# vidi-timeline - generate GStreamer Editing Services timelines from midi
+#
+# Copyright (C) 2016 Antonio Ospite <ao2@ao2.it>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+import os
+import sys
+import mido
+import vidi
+
+# TODO: turn that into a command line option
+ADD_REST_BACKGROUND = True
+
+
+def is_note(msg):
+ return msg.type == 'note_on' or msg.type == 'note_off'
+
+
+def is_note_on(msg):
+ return msg.type == 'note_on' and msg.velocity > 0
+
+
+def is_note_off(msg):
+ return ((msg.type == 'note_on' and msg.velocity == 0) or
+ (msg.type == 'note_off'))
+
+
+def check_overlapping_notes(midi_file):
+ previous_note_on = False
+ for msg in midi_file:
+ if is_note_on(msg) and msg.channel == 0:
+ if previous_note_on:
+ return True
+
+ previous_note_on = True
+ elif is_note_off(msg) and msg.channel == 0:
+ previous_note_on = False
+
+ return False
+
+
+def timeline_from_midi(midi_file, video_font_path):
+ timeline = vidi.Timeline()
+
+ elapsed_time = 0
+ start_time = 0
+ for msg in midi_file:
+ elapsed_time += msg.time
+ if is_note_on(msg) and msg.channel == 0:
+ start_time = elapsed_time
+ elif is_note_off(msg) and msg.channel == 0:
+ note = vidi.MidiNote(msg.note)
+ duration = elapsed_time - start_time
+ print("Note name: %3s start_time: %f duration: %f" %
+ (note.name, start_time, duration))
+
+ video_sample_path = "%s/sample_%s.webm" % (video_font_path, note.name)
+
+ timeline.add_clip(video_sample_path, start_time, duration)
+
+ if ADD_REST_BACKGROUND:
+ rest_sample_path = "%s/sample_rest.png" % video_font_path
+ timeline.add_layer_clip(rest_sample_path, 0, elapsed_time)
+
+ return timeline
+
+
+def usage():
+ print("usage: %s <midi_file> <videofont_directory> [<destination_file>]"
+ % os.path.basename(sys.argv[0]))
+
+
+def main():
+ if len(sys.argv) > 1 and sys.argv[1] in ["-h", "--help"]:
+ usage()
+ return 0
+
+ if len(sys.argv) < 3:
+ usage()
+ return 1
+
+ if not os.path.isdir(sys.argv[2]):
+ sys.stderr.write("The second argument must be the path of the videofont directory\n")
+ usage()
+ return 1
+
+ if len(sys.argv) > 3 and os.path.exists(sys.argv[3]):
+ sys.stderr.write("File '%s' exists, exiting!\n" % sys.argv[3])
+ return 1
+
+ midi_file = mido.MidiFile(sys.argv[1])
+
+ overlapping_notes = check_overlapping_notes(midi_file)
+ if overlapping_notes:
+ sys.stderr.write("Sorry, supporting only midi file with no overlapping notes on channel 0\n")
+ return 1
+
+ video_font_path = os.path.realpath(sys.argv[2])
+
+ timeline = timeline_from_midi(midi_file, video_font_path)
+
+ if len(sys.argv) > 3:
+ timeline.save(sys.argv[3])
+ else:
+ try:
+ timeline.play()
+ except KeyboardInterrupt:
+ timeline.stop()
+ return 1
+
+
+if __name__ == "__main__":
+ sys.exit(main())