From 38830460c24a214502698f0ba0c63d7e3c0b6082 Mon Sep 17 00:00:00 2001
From: sonora <hm.gglmail@gmail.com>
Date: Fri, 25 Sep 2015 18:09:09 +0200
Subject: [PATCH] test hdop-dependent turnaround detection threshold for GPX
 up/down analysis

---
 OsmAnd/src/net/osmand/plus/GPXUtilities.java | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/OsmAnd/src/net/osmand/plus/GPXUtilities.java b/OsmAnd/src/net/osmand/plus/GPXUtilities.java
index 6bf748db93..dc3ebcf0ad 100644
--- a/OsmAnd/src/net/osmand/plus/GPXUtilities.java
+++ b/OsmAnd/src/net/osmand/plus/GPXUtilities.java
@@ -226,7 +226,8 @@ public class GPXUtilities {
 			double totalSpeedSum = 0;
 			points = 0;
 			
-			double channelThres = 10;
+			double channelThresMin = 5;            // Minimum oscillation amplitude considered as noise for Up/Down analysis
+			double channelThres = channelThresMin; // Actual oscillation amplitude considered as noise, try depedency on current hdop
 			double channelBase;
 			double channelTop;
 			double channelBottom;
@@ -277,12 +278,19 @@ public class GPXUtilities {
 							channelBase = point.ele;
 							channelTop = channelBase;
 							channelBottom = channelBase;
+							channelThres = channelThresMin;
 						}
 						// Channel maintenance
 						if (point.ele > channelTop) {
 							channelTop = point.ele;
+							if (!Double.isNaN(point.hdop)) {
+								channelThres = Math.max(channelThres, point.hdop);
+							}
 						} else if (point.ele < channelBottom) {
 							channelBottom = point.ele;
+							if (!Double.isNaN(point.hdop)) {
+								channelThres = Math.max(channelThres, point.hdop);
+							}
 						}
 						// Turnaround (breakout) detection
 						if ((point.ele <= (channelTop - channelThres)) && (climb == true)) {
@@ -292,6 +300,7 @@ public class GPXUtilities {
 							channelBase = channelTop;
 							channelBottom = point.ele;
 							climb = false;
+							channelThres = channelThresMin;
 						} else if ((point.ele >= (channelBottom + channelThres)) && (climb == false)) {
 							if ((channelBase - channelBottom) >= channelThres) {
 								diffElevationDown += channelBase - channelBottom;
@@ -299,6 +308,7 @@ public class GPXUtilities {
 							channelBase = channelBottom;
 							channelTop = point.ele;
 							climb = true;
+							channelThres = channelThresMin;
 						}
 						// End detection without breakout
 						if (j == (numberOfPoints -1)) {