Updated Spectral effects to v4 plugins and added GPL v2 license information (with agreement from Paul Licameli).

plug-ins/SpectralEditShelves.ny

@@ -1,13 +1,22 @@
 ;nyquist plug-in
-;version 3
+;version 4
 ;type process
+;preview enabled
 ;name "Spectral edit shelves..."
-;action "Calculating..."
+;action "Filtering..."
 ;author "Paul Licameli"
-;copyright "Unknown"
+;copyright "Released under terms of the GNU General Public License version 2"
+
+
+;; SpectralEditShelves.ny by Paul Licameli, November 2014.
+;; Updated to version 4 by Steve Daulton November 2014.
+;; Released under terms of the GNU General Public License version 2:
+;; http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 
 ;control control-gain "Gain (dB)" real "" 0 -24 24
 
+(setf control-gain (min 24 (max -24 control-gain))) ; excessive settings may crash
+
 (defun mid-shelf (sig lf hf gain)
   "Combines high shelf and low shelf filters"
   (let* ((invg (- gain)))
@@ -16,23 +25,37 @@
                          hf invg))))
 
 (defun wet (sig gain)
-  (cond
-   ((not (or *f0* *f1*)) (throw 'debug-message "Please select frequencies"))
-   ((not *f0*) (eq-lowshelf sig *f1* gain))
-   ((not *f1*) (eq-highshelf sig *f0* gain))
-   (t (mid-shelf sig *f0* *f1* gain))))
+  (let ((f0 (get '*selection* 'low-hz))
+        (f1 (get '*selection* 'high-hz)))
+    (cond
+     ((not (or f0 f1))
+        (throw 'debug-message (format nil "~aPlease select frequencies." p-err)))
+     ((not f0) (eq-lowshelf sig f1 gain))
+     ((not f1) (eq-highshelf sig f0 gain))
+     (t (mid-shelf sig f0 f1 gain)))))
 
 (defun result (sig)
   (let*
       ((tn (truncate len))
        (rate (snd-srate sig))
-       (transition (truncate (* 0.01 rate)))
-       (t1 (min transition (/ tn 2)))
-       (t2 (max (- tn transition) (/ tn 2)))
+       (transition (truncate (* 0.01 rate)))  ; 10 ms
+       (t1 (min transition (/ tn 2)))         ; fade in length (samples)
+       (t2 (max (- tn transition) (/ tn 2)))  ; length before fade out (samples)
        (breakpoints (list t1 1.0 t2 1.0 tn))
        (env (snd-pwl 0.0 rate breakpoints)))
     (sum (prod env (wet sig control-gain)) (prod (diff 1.0 env) sig))))
 
-(catch 'debug-message
-  (multichan-expand #'result s))
+(cond
+  ((not (get '*TRACK* 'VIEW)) ; 'View is NIL during Preview
+      (setf p-err (format nil "This effect requires a frequency selction in the~%~
+                              'Spectrogram' or 'Spectrogram (log f)' track view.~%~%"))
+      (catch 'debug-message
+        (multichan-expand #'result *track*)))
+  ((string-not-equal (get '*TRACK* 'VIEW) "spectrogram"  :end1 4 :end2 4)
+      "Use this effect in the 'Spectrogram'\nor 'Spectrogram (log f)' view.")
+  (T  (setf p-err "")
+      (if (= control-gain 0)  ; Allow dry preview
+          "Gain is zero. Nothing to do."
+          (catch 'debug-message
+            (multichan-expand #'result *track*)))))