From c0763f592a1d220f8298ef1860ae4e74329d4f27 Mon Sep 17 00:00:00 2001
From: "Reece H. Dunn" <msclrhd@gmail.com>
Date: Wed, 25 Jan 2017 23:28:55 +0000
Subject: [PATCH] phoneme_add_feature: recognize vowel features.

---
 src/libespeak-ng/phoneme.c | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/src/libespeak-ng/phoneme.c b/src/libespeak-ng/phoneme.c
index bebf6a19..3b0ed7b5 100644
--- a/src/libespeak-ng/phoneme.c
+++ b/src/libespeak-ng/phoneme.c
@@ -65,6 +65,21 @@ enum feature_t {
 	// voice
 	vcd = FEATURE('v', 'c', 'd'),
 	vls = FEATURE('v', 'l', 's'),
+	// vowel height
+	hgh = FEATURE('h', 'g', 'h'),
+	smh = FEATURE('s', 'm', 'h'),
+	umd = FEATURE('u', 'm', 'd'),
+	mid = FEATURE('m', 'i', 'd'),
+	lmd = FEATURE('l', 'm', 'd'),
+	sml = FEATURE('s', 'm', 'l'),
+	low = FEATURE('l', 'o', 'w'),
+	// vowel backness
+	fnt = FEATURE('f', 'n', 't'),
+	cnt = FEATURE('c', 'n', 't'),
+	bck = FEATURE('b', 'c', 'k'),
+	// rounding
+	unr = FEATURE('u', 'n', 'r'),
+	rnd = FEATURE('r', 'n', 'd'),
 };
 
 uint32_t lookup_feature(const char *feature) {
@@ -174,6 +189,27 @@ phoneme_add_feature(PHONEME_TAB *phoneme,
 	case vls:
 		phoneme->phflags |= phVOICELESS;
 		break;
+	// vowel height
+	case hgh:
+	case smh:
+	case umd:
+	case mid:
+	case lmd:
+	case sml:
+	case low:
+		// Not supported by eSpeak.
+		break;
+	// vowel backness
+	case fnt:
+	case cnt:
+	case bck:
+		// Not supported by eSpeak.
+		break;
+	// rounding
+	case unr:
+	case rnd:
+		// Not supported by eSpeak.
+		break;
 	// invalid phoneme feature
 	default:
 		return create_name_error_context(context, ENS_UNKNOWN_PHONEME_FEATURE, feature);