Port to espeak-ng

- use "english" as default voice when built with espeak-ng 1.49 and
  later,

- use "default" when built with espeak 1.48 and earlier,

- fixes Debian #877750 ("silence, loops, and errors if no voice set"),

- regression caused by espeak-ng 59ca718 ("Always use 'en' as the
  default voice/language.")

src/espeak.c

@@ -127,6 +127,14 @@ static GValueArray *espeak_voices = NULL;
 
 // -----------------------------------------------------------------------------
 
+const char* espeak_default_voice() {
+#if ESPEAK_API_REVISION < 10
+    return "default";
+#else
+    return "english";
+#endif
+}
+
 Econtext *espeak_new (GstElement * emitter) {
     init ();
 
@@ -150,7 +158,7 @@ Econtext *espeak_new (GstElement * emitter) {
 
     self->pitch = 50;
     self->rate = 170;
-    self->voice = ESPEAK_DEFAULT_VOICE;
+    self->voice = espeak_default_voice();
     self->gap = 0;
     self->track = ESPEAK_TRACK_NONE;
 

src/espeak.h

@@ -18,15 +18,14 @@
 #ifndef ESPEAK_H
 #define ESPEAK_H
 
-#define ESPEAK_DEFAULT_VOICE  "default"
-
 #define ESPEAK_TRACK_NONE 0
 #define ESPEAK_TRACK_WORD 1
 #define ESPEAK_TRACK_MARK 2
 
 struct _Econtext;
 typedef struct _Econtext Econtext;
 
+const char* espeak_default_voice();
 Econtext *espeak_new (GstElement *);
 void espeak_unref (Econtext *);
 

src/gstespeak.c

@@ -106,7 +106,7 @@ static void gst_espeak_class_init (GstEspeakClass * klass) {
                     G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
     g_object_class_install_property (gobject_class, PROP_VOICE,
             g_param_spec_string ("voice", "Current voice",
-                    "Current voice", ESPEAK_DEFAULT_VOICE,
+                    "Current voice", espeak_default_voice (),
                     G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
     g_object_class_install_property (gobject_class, PROP_GAP,
             g_param_spec_uint ("gap", "Gap",
@@ -144,7 +144,7 @@ static void gst_espeak_init (GstEspeak * self) {
     self->text = NULL;
     self->pitch = 0;
     self->rate = 0;
-    self->voice = g_strdup (ESPEAK_DEFAULT_VOICE);
+    self->voice = g_strdup (espeak_default_voice ());
     self->voices = espeak_get_voices ();
     self->speak = espeak_new (GST_ELEMENT (self));