diff --git a/samples/geotag.cpp b/samples/geotag.cpp
index 13558276..0a1ff807 100644
--- a/samples/geotag.cpp
+++ b/samples/geotag.cpp
@@ -150,11 +150,31 @@ strings_t    gFiles;
 class Position
 {
 public:
-             Position(time_t time,double lat,double lon,double ele) : time_(time),lon_(lon),lat_(lat),ele_(ele) {};
-             Position() { time_=0 ; lon_=0.0 ; lat_=0.0 ; ele_=0.0 ; };
-    virtual ~Position() {} ;
+    Position(time_t time, double lat, double lon, double ele) :
+        time_(time)
+      , lon_(lon)
+      , lat_(lat)
+      , ele_(ele)
+      , delta_(0)
+    {}
+
+    Position():
+        time_(0)
+      , lon_(0.0)
+      , lat_(0.0)
+      , ele_(0.0)
+      , delta_(0)
+    { }
+
+    virtual ~Position() {}
 //  copy constructor
-    Position(const Position& o) : time_(o.time_),lon_(o.lon_),lat_(o.lat_),ele_(o.ele_) {};
+    Position(const Position& o) :
+        time_(o.time_)
+      , lon_(o.lon_)
+      , lat_(o.lat_)
+      , ele_(o.ele_)
+      , delta_(o.delta_)
+    {}
 
 //  instance methods
     bool good()                 { return time_ || lon_ || lat_ || ele_ ; }
@@ -262,8 +282,18 @@ time_t Position::deltaMax_ = 60 ;
 class UserData
 {
 public:
-    UserData(Options& options) : indent(0),count(0),nTrkpt(0),bTime(false),bEle(false),options_(options) {};
-    virtual ~UserData() {} ;
+    UserData(Options& options):
+        indent(0)
+      , count(0)
+      , nTrkpt(0)
+      , bTime(false)
+      , bEle(false)
+      , ele(0.0)
+      , lat(0.0)
+      , lon(0.0)
+      , options_(options)
+    {}
+    virtual ~UserData() {}
 
 //  public data members
     int         indent;
diff --git a/src/preview.cpp b/src/preview.cpp
index 820ef65e..f2242805 100644
--- a/src/preview.cpp
+++ b/src/preview.cpp
@@ -933,9 +933,11 @@ namespace {
 
         // create decoding table
         unsigned long invalid = 64;
-        unsigned long decodeBase64Table[256];
-        for (unsigned long i = 0; i < 256; i++) decodeBase64Table[i] = invalid;
-        for (unsigned long i = 0; i < 64; i++) decodeBase64Table[(unsigned char)encodeBase64Table[i]] = i;
+        unsigned long decodeBase64Table[256] = {};
+        for (unsigned long i = 0; i < 256; i++)
+            decodeBase64Table[i] = invalid;
+        for (unsigned long i = 0; i < 64; i++)
+            decodeBase64Table[(unsigned char)encodeBase64Table[i]] = i;
 
         // calculate dest size
         unsigned long validSrcSize = 0;
diff --git a/src/types.cpp b/src/types.cpp
index 6a3bbc34..dc059c11 100644
--- a/src/types.cpp
+++ b/src/types.cpp
@@ -209,18 +209,20 @@ namespace Exiv2 {
     {
         // http://dev.exiv2.org/boards/3/topics/1912?r=1915
         if ( std::tolower(is.peek()) == 'f' ) {
-            char  F;
-            float f;
+            char  F = 0;
+            float f = 0.f;
             is >> F >> f ;
             f  = 2.0f * std::log(f) / std::log(2.0f) ;
             r  = Exiv2::floatToRationalCast(f);
         } else {
-            int32_t nominator;
-            int32_t denominator;
+            int32_t nominator = 0;
+            int32_t denominator = 0;
             char c('\0');
             is >> nominator >> c >> denominator;
-            if (c != '/') is.setstate(std::ios::failbit);
-            if (is) r = std::make_pair(nominator, denominator);
+            if (c != '/')
+                is.setstate(std::ios::failbit);
+            if (is)
+                r = std::make_pair(nominator, denominator);
         }
         return is;
     }
@@ -233,19 +235,22 @@ namespace Exiv2 {
     std::istream& operator>>(std::istream& is, URational& r)
     {
         // http://dev.exiv2.org/boards/3/topics/1912?r=1915
+        /// \todo This implementation seems to be duplicated for the Rational type. Try to remove duplication
         if ( std::tolower(is.peek()) == 'f' ) {
-            char  F;
-            float f;
+            char  F = 0;
+            float f = 0.f;
             is >> F >> f ;
             f  = 2.0f * std::log(f) / std::log(2.0f) ;
             r  = Exiv2::floatToRationalCast(f);
         } else {
-            uint32_t nominator;
-            uint32_t denominator;
+            uint32_t nominator = 0;
+            uint32_t denominator = 0;
             char c('\0');
             is >> nominator >> c >> denominator;
-            if (c != '/') is.setstate(std::ios::failbit);
-            if (is) r = std::make_pair(nominator, denominator);
+            if (c != '/')
+                is.setstate(std::ios::failbit);
+            if (is)
+                r = std::make_pair(nominator, denominator);
         }
         return is;
     }