File: singing-mode.scm

package info (click to toggle)
festival 1%3A2.4~release-3
  • links: PTS, VCS
  • area: main
  • in suites: stretch
  • size: 7,432 kB
  • ctags: 6,364
  • sloc: cpp: 27,729; lisp: 15,695; ansic: 6,022; sh: 5,660; java: 1,536; makefile: 769; xml: 291; perl: 87
file content (673 lines) | stat: -rw-r--r-- 23,592 bytes parent folder | download | duplicates (3)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;
;;; Festival Singing Mode
;;;
;;; Written by Dominic Mazzoni
;;; Carnegie Mellon University
;;; 11-752 - "Speech: Phonetics, Prosody, Perception and Synthesis"
;;; Spring 2001
;;;
;;; Extended by Milan Zamazal <pdm@brailcom.org>, 2006:
;;; - Slur support.
;;; - Czech support.
;;; - Some cleanup.
;;; - Print debugging information only when singing-debug is true.
;;;
;;; This code is public domain; anyone may use it freely.
;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(require_module 'rxp)

(xml_register_id "-//SINGING//DTD SINGING mark up//EN"
		(path-append xml_dtd_dir "Singing.v0_1.dtd")
		)

(xml_register_id "-//SINGING//ENTITIES Added Latin 1 for SINGING//EN"
		 (path-append xml_dtd_dir  "sable-latin.ent")
		 )

;; Set this to t to enable debugging messages:
(defvar singing-debug nil)

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;
;; XML parsing functions
;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

;;
;; singing_xml_targets
;;
;; This variable defines the actions that are to be taken when
;; parsing each of our XML tags: SINGING, PITCH, DURATION, and REST.
;;
;; When we get the pitch and duration of each token, we store them
;; in features of the token.  Later our intonation and duration
;; functions access these features.
;;

(defvar singing_xml_elements
  '(
    ("(SINGING" (ATTLIST UTT)
     (set! singing_pitch_att_list nil)
     (set! singing_dur_att_list nil)
     (set! singing_global_time 0.0)
     (set! singing_bpm (get-bpm ATTLIST))
     (set! singing_bps (/ singing_bpm 50.0)) ;; change this back to 60
     nil)

    (")SINGING" (ATTLIST UTT)
     (xxml_synth UTT)  ;;  Synthesize the remaining tokens
     nil)

    ("(PITCH" (ATTLIST UTT)
     (set! singing_pitch_att_list ATTLIST)
     UTT)

    (")PITCH" (ATTLIST UTT)
     (let ((freq (get-freqs singing_pitch_att_list)))
       (if singing-debug
           (begin
             (print "freqs")
             (print freq)))
       (singing-append-feature! UTT 'freq freq))
     UTT)
    
    ("(DURATION" (ATTLIST UTT)
     (set! singing_dur_att_list ATTLIST)
     UTT)

    (")DURATION" (ATTLIST UTT)
     (let ((dur (get-durs singing_dur_att_list)))
       (if singing-debug
           (begin
             (print "durs")
             (print dur)))
       (singing-append-feature! UTT 'dur dur))
     UTT)
    
    ("(REST" (ATTLIST UTT)
     (let ((dur (get-durs ATTLIST)))
       (if singing-debug
           (begin
             (print "rest durs")
             (print dur)))
       (singing-append-feature! UTT 'rest (caar dur)))
     UTT)
    ))

;;
;; get-bpm
;;
;; Given the attribute list of a SINGING tag, returns the beats
;; per minute of the song from the BPM parameter.
;;

(define (get-bpm atts)
  (parse-number (car (car (cdr (assoc 'BPM atts))))))

;;
;; get-durs
;;
;; Given the attribute list of a DURATION tag, returns a list of
;; durations in seconds for the syllables of the word enclosed by
;; this tag.
;;
;; It first looks for a BEATS parameter, and converts these to
;; seconds using BPM, which was set in the SINGING tag.  If this
;; is not present, it looks for the SECONDS parameter.
;;

(define (get-durs atts)
  (let ((seconds (car (car (cdr (assoc 'SECONDS atts)))))
        (beats (car (car (cdr (assoc 'BEATS atts))))))
    (if (equal? beats 'X)
        (mapcar (lambda (lst) (mapcar parse-number lst))
                (string->list seconds))
        (mapcar (lambda (lst)
                  (mapcar (lambda (x) (/ (parse-number x) singing_bps)) lst))
                (string->list beats)))))

;;
;; get-freqs
;;
;; Given the attribute list of a PITCH tag, returns a list of
;; frequencies in Hertz for the syllables of the word enclosed by
;; this tag.
;;
;; It first looks for a NOTE parameter, which can contain a MIDI
;; note of the form "C4", "D#3", or "Ab6", and if this is not
;; present it looks for the FREQ parameter.
;;

(define (get-freqs atts)
  (let ((freqs (car (car (cdr (assoc 'FREQ atts)))))
        (notes (car (car (cdr (assoc 'NOTE atts))))))
    (if (equal? notes 'X)
        (mapcar (lambda (lst) (mapcar parse-number lst))
                (string->list freqs))
        (mapcar (lambda (lst) (mapcar note->freq lst))
                (string->list notes)))))

;;
;; note->freq
;;
;; Converts a string representing a MIDI note such as "C4" and
;; turns it into a frequency.  We use the convention that
;; A5=440 (some call this note A3).
;;

(define (note->freq note)
  (if singing-debug
      (format t "note is %l\n" note))
  (set! note (format nil "%s" note))
  (if singing-debug
      (print_string note))
  (let (l octave notename midinote thefreq)
    (set! l (string-length note))
    (set! octave (substring note (- l 1) 1))
    (set! notename (substring note 0 (- l 1)))
    (set! midinote (+ (* 12 (parse-number octave))
                      (notename->midioffset notename)))
    (set! thefreq (midinote->freq midinote))
    (if singing-debug
        (format t "note %s freq %f\n" note thefreq))
    thefreq))

;;
;; midinote->freq
;;
;; Converts a MIDI note number (1 - 127) into a frequency.  We use
;; the convention that 69 = "A5" =440 Hz.
;;

(define (midinote->freq midinote)
  (* 440.0 (pow 2.0 (/ (- midinote 69) 12))))

;;
;; notename->midioffset
;;
;; Utility function that looks up the name of a note like "F#" and
;; returns its offset from C.
;;

(define (notename->midioffset notename)
  (parse-number (car (cdr (assoc_string notename note_names)))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;
;; Pitch modification functions
;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

;;
;; singing_f0_targets
;;
;; This function replaces the normal intonation function used in
;; festival.  For each syllable, it extracts the frequency that
;; was calculated from the XML tags and stored in the token this
;; syllable comes from, and sets this frequency as both the start
;; and end f0 target.  Really straightforward!
;;

(defvar singing-last-f0 nil)
(define (singing_f0_targets utt syl)
  "(singing_f0_targets utt syl)"
  (let ((start (item.feat syl 'syllable_start))
        (end (item.feat syl 'syllable_end))
        (freqs (mapcar parse-number (syl->freq syl)))
        (durs (syl->durations syl)))
    (let ((total-durs (apply + durs))
          (total-time (- end start))
          (time start)
          (prev-segment (item.prev (item.relation (item.daughter1 (item.relation syl 'SylStructure)) 'Segment)))
          (last-f0 singing-last-f0))
      (if freqs
          (begin
            (set! singing-last-f0 (car (last freqs)))
            (append (if (and last-f0
                             prev-segment
                             (item.prev prev-segment)
                             (string-equal (item.feat prev-segment 'name)
                                           (car (car (cdr (car (PhoneSet.description '(silences))))))))
                        (let ((s (item.feat prev-segment "p.end"))
                              (e (item.feat prev-segment "end")))
                          (list (list (+ s (* (- e s) 0.8)) last-f0)
                                (list (+ s (* (- e s) 0.9)) (car freqs)))))
                    (apply append
                           (mapcar (lambda (d f)
                                     (let ((range (* (/ d total-durs) total-time))
                                           (old-time time))
                                       (set! time (+ time range))
                                       (let ((range-fraction (* 0.1 range)))
                                         (list (list (+ old-time range-fraction) f)
                                               (list (- time range-fraction) f)))))
                                   durs freqs))))))))

;;
;; syl->freq
;;
;; Given a syllable, looks up the frequency in its token.  The token
;; stores a list of all of the frequencies associated with its
;; syllables, so this syllable grabs the frequency out of the list
;; corresponding to its index within the word.  (This assumes that
;; a frequency was given for each syllable, and that a token
;; corresponds directly to a word.  Singing-mode is not guaranteed
;; to work at all if either of these things are not true.)
;;

(define (syl->freq syl)
  (let ((index (item.feat syl "R:Syllable.pos_in_word"))
        (freqs (singing-feat syl "R:SylStructure.parent.R:Token.parent.freq")))
    (nth index freqs)))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;
;; Duration modification functions
;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

;;
;; singing_duration_method 
;;
;; Calculates the duration of each phone in the utterance, in three
;; passes.  Consult the three functions it calls, below, to see what
;; each one does.
;;

(define (singing_duration_method utt)
  (mapcar singing_adjcons_syllable (utt.relation.items utt 'Syllable))
  (singing_do_initial utt (car (utt.relation.items utt 'Token)))
  (mapcar singing_do_syllable (utt.relation.items utt 'Syllable))
  (mapcar singing_fix_segment (utt.relation.items utt 'Segment))
  utt)

;;
;; singing_adjcons_syllable
;;
;; First pass.  Looks at the first phone of each syllable and
;; adjusts the starting time of this syllable such that the
;; perceived start time of the first phone is at the beginning
;; of the originally intended start time of the syllable.
;;
;; If this is not done, telling it to say the word "ta" at time
;; 2.0 actually doesn't "sound" like it says the "t" sound until
;; about 2.1 seconds.
;;
;; This function has a little bit of duplicated code from
;; singing_do_syllable, below - it could be modularized a little
;; better.
;;

(define (singing_adjcons_syllable syl)
  (let ((totlen (apply + (mapcar (lambda (s)
                                   (get_avg_duration (item.feat s "name")))
                                 (item.leafs
                                  (item.relation syl 'SylStructure)))))
        (syldur (apply + (syl->durations syl)))
        ;; figure out the offset of the first phone
        (phone1 (item.daughter1 (item.relation syl 'SylStructure)))
        (prevsyl (item.prev (item.relation syl 'Syllable))))
    (let ((offset (get_duration_offset (item.feat phone1 "name"))))
      (if singing-debug
          (format t "offset: %f\n" offset) )
      (if (< syldur totlen)
          (set! offset (* offset (/ syldur totlen))))
      (if singing-debug
          (format t "Want to adjust syl by %f\n" offset))
      (if prevsyl
          (begin
            (item.set_feat prevsyl 'subtractoffset offset)
            (item.set_feat syl 'addoffset offset))))))

;;
;; singing_do_syllable
;;
;; Second pass.  For each syllable, adds up the amount of time
;; that would normally be spent in consonants and vowels, based
;; on the average durations of these phones.  Then, if the
;; intended length of this syllable is longer than this total,
;; stretch only the vowels; otherwise shrink all phones
;; proportionally.  This function actually sets the "end" time
;; of each phone using a global "singing_global_time" variable.
;;
;; We also handle rests at this point, which are tagged onto the
;; end of the previous token.
;;

(defvar singing-max-short-vowel-length 0.11)

(define (singing_do_initial utt token)
  (if (equal? (item.name token) "")
      (let ((restlen (car (item.feat token 'rest))))
        (if singing-debug
            (format t "restlen %l\n" restlen))
        (if (> restlen 0)
            (let ((silence (car (car (cdr (assoc 'silences (PhoneSet.description)))))))
              (set! singing_global_time restlen)
              (item.relation.insert (utt.relation.first utt 'Segment) 'Segment
                                    (list silence (list (list "end" singing_global_time)))
                                    'before))))))

(define (singing_do_syllable syl)
  (let ((conslen 0.0)
        (vowlen 0.0)
        (segments (item.leafs (item.relation syl 'SylStructure))))
    ;; if there are no vowels, turn a middle consonant into a vowel;
    ;; hopefully this works well for languages where syllables may be
    ;; created by some consonants too
    (let ((segments* segments)
          (vowel-found nil))
      (while (and segments* (not vowel-found))
        (if (equal? "+" (item.feat (car segments*) "ph_vc"))
            (set! vowel-found t)
            (set! segments* (cdr segments*))))
      (if (not vowel-found)
          (item.set_feat (nth (nint (/ (- (length segments) 1) 2))
                              segments)
                         "singing-vc" "+")))
    ;; sum up the length of all of the vowels and consonants in
    ;; this syllable
    (mapcar (lambda (s)
              (let ((slen (get_avg_duration (item.feat s "name"))))
                (if (or (equal? "+" (item.feat s "ph_vc"))
                        (equal? "+" (item.feat s "singing-vc")))
                    (set! vowlen (+ vowlen slen))
                    (set! conslen (+ conslen slen)))))
            segments)
    (let ((totlen (+ conslen vowlen))
          (syldur (apply + (syl->durations syl)))
          (addoffset (item.feat syl 'addoffset))
          (subtractoffset (item.feat syl 'subtractoffset))
          offset)
      (set! offset (- subtractoffset addoffset))
      (if singing-debug
          (format t "Vowlen: %f conslen: %f totlen: %f\n" vowlen conslen totlen))
      (if (< offset (/ syldur 2.0))
	  (begin
            (set! syldur (- syldur offset))
            (if singing-debug
                (format t "Offset: %f\n" offset))))
      (if singing-debug
          (format t "Syldur: %f\n" syldur))
      (if (> totlen syldur)
	  ;; if the total length of the average durations in the syllable is
	  ;; greater than the total desired duration of the syllable, stretch
	  ;; the time proportionally for each phone
	  (let ((stretch (/ syldur totlen)))
            (mapcar (lambda (s)
                      (let ((slen (* stretch (get_avg_duration (item.feat s "name")))))
                        (set! singing_global_time (+ slen singing_global_time))
                        (item.set_feat s 'end singing_global_time)))
                    (item.leafs (item.relation syl 'SylStructure))))
	  ;; otherwise, stretch the vowels and not the consonants
	  (let ((voweltime (- syldur conslen)))
            (let ((vowelstretch (/ voweltime vowlen))
                  (phones (mapcar car (car (cdar (PhoneSet.description '(phones)))))))
              (mapcar (lambda (s)
                        (let ((slen (get_avg_duration (item.feat s "name"))))
                          (if (or (equal? "+" (item.feat s "ph_vc"))
                                  (equal? "+" (item.feat s "singing-vc")))
                              (begin
                                (set! slen (* vowelstretch slen))
                                ;; If the sound is long enough, better results
                                ;; may be achieved by using longer versions of
                                ;; the vowels.
                                (if (> slen singing-max-short-vowel-length)
                                    (let ((sname (string-append (item.feat s "name") ":")))
                                      (if (member_string sname phones)
                                          (item.set_feat s "name" sname))))))
                          (set! singing_global_time (+ slen singing_global_time))
                          (item.set_feat s 'end singing_global_time)))
                      segments))))))
  (let ((restlen (car (syl->rest syl))))
    (if singing-debug
        (format t "restlen %l\n" restlen))
    (if (> restlen 0)
        (let ((lastseg (item.daughtern (item.relation syl 'SylStructure)))
              (silence (car (car (cdr (assoc 'silences (PhoneSet.description))))))
              (singing_global_time* singing_global_time))
          (let ((seg (item.relation lastseg 'Segment))
                (extra-pause-length 0.00001))
            (set! singing_global_time (+ restlen singing_global_time))
            (item.insert seg (list silence (list (list "end" singing_global_time))) 'after)
            ;; insert a very short extra pause to avoid after-effects, especially
            ;; after vowels
            (if (and seg
                     (equal? (item.feat seg "ph_vc") "+")
                     (< extra-pause-length restlen))
                (item.insert seg (list silence (list (list "end" (+ singing_global_time*
                                                                extra-pause-length))))
                             'after)))))))

;;
;; singing_fix_segment
;;
;; Third pass.  Finds any segments (phones) that we didn't catch earlier
;; (say if they didn't belong to a syllable, like silence) and sets them
;; to zero duration
;;

(define (singing_fix_segment seg)
  (if (equal? 0.0 (item.feat seg 'end))
      (if (equal? nil (item.prev seg))
          (item.set_feat seg 'end 0.0)
          (item.set_feat seg 'end (item.feat (item.prev seg) 'end)))
      (if singing-debug
          (format t "segment: %s end: %f\n" (item.name seg) (item.feat seg 'end)))))
  
;; returns the duration of a syllable (stored in its token)
(define (syl->durations syl)
  (let ((index (item.feat syl "R:Syllable.pos_in_word"))
        (durs (singing-feat syl "R:SylStructure.parent.R:Token.parent.dur")))
    (mapcar parse-number (nth index durs))))

;; returns the duration of the rest following a syllable
(define (syl->rest syl)
  (let ((index (item.feat syl "R:Syllable.pos_in_word"))
        (durs (singing-feat syl "R:SylStructure.parent.R:Token.parent.dur"))
        (pauselen (singing-feat syl "R:SylStructure.parent.R:Token.parent.rest")))
    (if (equal? index (- (length durs) 1))
        (list (or pauselen 0.0))
        (list 0.0))))

;; get the average duration of a phone
(define (get_avg_duration phone)
  (let ((pd (assoc_string phone phoneme_durations)))
    (if pd
	(car (cdr pd))
	0.08)))

;; get the duration offset of a phone (see the description above)
(define (get_duration_offset phone)
  (parse-number (car (cdr (assoc_string phone phoneme_offsets*)))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;
;; Other utility functions
;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define (char-quote string)
  (if (member string '("*" "+" "?" "[" "]" "."))
      (string-append "[" string "]")
      string))

(define (split-string string separator)
  (if (string-matches string (string-append ".+" (char-quote separator) ".+"))
      (cons (string-before string separator)
            (split-string (string-after string separator) separator))
      ;; We have to convert the weird XML attribute value type to string
      (list (string-append string ""))))

(define (string->list string)
  (mapcar (lambda (s) (split-string s "+")) (split-string string ",")))

(define (singing-append-feature! utt feature value)
  (let ((tokens (utt.relation.items utt 'Token)))
    (if tokens
        ;; we have to wrap value into a list to work around a Festival bug
        (item.set_feat (car (last tokens)) feature (list value))
        (begin
          (utt.relation.append utt 'Token '("" ((name "") (whitespace "")
                                                (prepunctuation "") (punc ""))))
          (item.set_feat (car (last (utt.relation.items utt 'Token))) feature (list value))))))

(define (singing-feat item feature)
  (let ((value (item.feat item feature)))
    (if (equal? value 0)
        nil
        (car value))))

(define (current-language)
  (cadr (car (assoc 'language (voice.description current-voice)))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;
;; Initializing and exiting singing mode
;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

;;
;; singing_init_func
;;

(defvar singing_previous_eou_tree nil)

(define (singing_init_func)
  "(singing_init_func) - Initialization for Singing mode"
  (if (not (symbol-bound? 'phoneme_durations))
      (set! phoneme_durations '()))
  ;; use our intonation function
  (Parameter.set 'Int_Method 'General)
  (Parameter.set 'Int_Target_Method Int_Targets_General)
  (set! int_general_params `((targ_func ,singing_f0_targets)))
  (set! singing-last-f0 nil)
  ;; use our duration function
  (Parameter.set 'Duration_Method singing_duration_method)
  ;; set phoneme corrections for the current language
  (let ((language 'english
;         (cadr (assoc 'language
;                               (cadr (voice.description current-voice))))
         ))
    (set! phoneme_offsets* (cdr (assoc language phoneme_offsets))))
  ;; avoid splitting to multiple utterances with insertion of unwanted pauses
  (set! singing_previous_eou_tree eou_tree)
  (set! eou_tree nil)
  ;; use our xml parsing function
  (set! singing_previous_elements xxml_elements)
  (set! xxml_elements singing_xml_elements))

;;
;; singing_exit_func
;;

(define (singing_exit_func)
  "(singing_exit_func) - Exit function for Singing mode"
  (set! eou_tree singing_previous_eou_tree)
  (set! xxml_elements singing_previous_elements))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;
;; Data tables
;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defvar note_names
  '((C 0)
    (C# 1)
    (Db 1)
    (D 2)
    (D# 3)
    (Eb 3)
    (E 4)
    (E# 5)
    (Fb 4)
    (F 5)
    (F# 6)
    (Gb 6)
    (G 7)
    (G# 8)
    (Ab 8)
    (A 9)
    (A# 10)
    (Bb 10)
    (B 11)
    (B# 12)
    (Cb 11)))

;;
;; The following list contains the offset into each phone that best
;; represents the perceptual onset of the phone.  This is important
;; to know to get durations right in singing.  For example, if the
;; offset for "t" is .060, and you want to start a "t" sound at
;; time 2.0 seconds, you should actually start the phone playing
;; at time 1.940 seconds in order for it to sound like the onset of
;; the "t" is really right at 2.0.
;;
;; These were derived empically by looking at and listening to the
;; waveforms of each phone for mwm's voice.
;;

(defvar phoneme_offsets
  `((english (t 0.050)
             (T 0.050)
             (d 0.090)
             (D 0.090)
             (p 0.080)
             (b 0.080)
             (k 0.090)
             (g 0.100)
             (9r 0.050) ;; r
             (l 0.030)
             (f 0.050)
             (v 0.050)
             (s 0.040)
             (S 0.040)
             (z 0.040)
             (Z 0.040)
             (n 0.040)
             (N 0.040)
             (m 0.040)
             (j 0.090)
             (E 0.0)
             (> 0.0)
             (>i 0.0)
             (aI 0.0)
             (& 0.0)
             (3r 0.0)
             (tS 0.0)
             (oU 0.0)
             (aU 0.0)
             (A 0.0)
             (ei 0.0)
             (iU 0.0)
             (U 0.0)
             (@ 0.0)
             (h 0.0)
             (u 0.0)
             (^ 0.0)
             (I 0.0)
             (dZ 0.0)
             (i: 0.0)
             (w 0.0)
             (pau 0.0)
             (brth 0.0)
             (h# 0.0)
             )))

(defvar phoneme_offsets* nil)

;;
;; Declare the new mode to Festival
;;

(set! tts_text_modes
      (cons `(singing   ;; mode name
              ((init_func ,singing_init_func)
               (exit_func ,singing_exit_func)
               (analysis_type xml)))
            tts_text_modes))

(provide 'singing-mode)