1 files changed, 66 insertions, 0 deletions
diff --git a/libarmep/avg-mean-us.c b/libarmep/avg-mean-us.c
new file mode 100644
index 0000000..6d680d9
--- /dev/null
+++ b/libarmep/avg-mean-us.c
@@ -0,0 +1,66 @@
+/*
+ * Author: Andy Green <andy.green@linaro.org> 
+ * Copyright (C) 2012 Linaro, LTD
+ *
+ * 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 2
+ * 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, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ */
+
+#include <stdlib.h>
+#include <malloc.h>
+#include "libarmep.h"
+                                                                                
+int avg_mean_us_init(struct avg_mean_us *amu, int width)
+{
+	amu->ring = malloc(width * sizeof(unsigned short));
+	if (amu->ring == NULL)
+		return 1;
+	amu->width = width;
+	amu->count = 0;
+	amu->next = 0;
+	amu->sum = 0;
+
+	return 0;
+}
+void avg_mean_us_add(struct avg_mean_us *amu, unsigned short s)
+{
+	if (amu->count == amu->width)
+		amu->sum -= amu->ring[amu->next];
+	else
+		amu->count++;
+
+	amu->ring[amu->next++] = s;
+	if (amu->next == amu->width)
+		amu->next = 0;
+	amu->sum += s;
+}
+
+double avg_mean_us(struct avg_mean_us *amu)
+{
+	return (double)amu->sum / (double)amu->count;
+}
+
+void avg_mean_us_free(struct avg_mean_us *amu)
+{
+	free(amu->ring);
+}
+
+void avg_mean_us_flush(struct avg_mean_us *amu)
+{
+	amu->count = 0;
+	amu->sum = 0;
+	amu->next = 0;
+}