diff --git a/include/mapnik/attribute_collector.hpp b/include/mapnik/attribute_collector.hpp
index f97e5d23b..1d4fb374a 100644
--- a/include/mapnik/attribute_collector.hpp
+++ b/include/mapnik/attribute_collector.hpp
@@ -199,6 +199,11 @@ struct symbolizer_attributes : public boost::static_visitor<>
         {
             boost::apply_visitor(f_attr,*width_expr);
         }
+        path_expression_ptr const& filename_expr = sym.get_filename();
+        if (filename_expr)
+        {
+            path_processor_type::collect_attributes(*filename_expr,names_);
+        }
         collect_transform(sym.get_image_transform());
         collect_transform(sym.get_transform());
     }
diff --git a/include/mapnik/placement_finder.hpp b/include/mapnik/placement_finder.hpp
index 1c5f67c10..0af9e1479 100644
--- a/include/mapnik/placement_finder.hpp
+++ b/include/mapnik/placement_finder.hpp
@@ -33,11 +33,9 @@
 #include <mapnik/ctrans.hpp>
 #include <mapnik/noncopyable.hpp>
 
-
 // agg
 #include "agg_conv_clip_polyline.h"
 
-
 // stl
 #include <queue>
 
@@ -65,21 +63,21 @@ public:
                      DetectorT & detector,
                      box2d<double> const& extent);
 
-    /** Try place a single label at the given point. */
+    // Try place a single label at the given point. */
     void find_point_placement(double pos_x, double pos_y, double angle=0.0);
 
-    /** Iterate over the given path, placing point labels with respect to label_spacing. */
+    // Iterate over the given path, placing point labels with respect to label_spacing. */
     template <typename T>
     void find_point_placements(T & path);
 
-    /** Iterate over the given path, placing line-following labels with respect to label_spacing. */
+    // Iterate over the given path, placing line-following labels with respect to label_spacing. */
     template <typename T>
     void find_line_placements(T & path);
 
-    /** Add placements to detector. */
+    // Add placements to detector. */
     void update_detector();
 
-    /** Remove old placements. */
+    // Remove old placements. */
     void clear_placements();
 
     inline placements_type const& get_results() { return placements_; }
@@ -134,17 +132,14 @@ private:
     string_info const& info_;
     text_symbolizer_properties const& p;
     text_placement_info const& pi;
-    /** Length of the longest line after linebreaks.
-     * Before find_line_breaks() this is the total length of the string.
-     */
+    // Length of the longest line after linebreaks.
+    // Before find_line_breaks() this is the total length of the string.
     double string_width_;
-    /** Height of the string after linebreaks.
-     * Before find_line_breaks() this is the total length of the string.
-     */
+    // Height of the string after linebreaks.
+    // Before find_line_breaks() this is the total length of the string.
     double string_height_;
-    /** Height of the tallest font in the first line not including line spacing.
-     * Used to determine the correct offset for the first line.
-     */
+    // Height of the tallest font in the first line not including line spacing.
+    // Used to determine the correct offset for the first line.
     double first_line_space_;
     vertical_alignment_e valign_;
     horizontal_alignment_e halign_;
@@ -152,18 +147,17 @@ private:
     std::vector<unsigned> line_breaks_;
     std::vector<std::pair<double, double> > line_sizes_;
     std::queue< box2d<double> > envelopes_;
-    /** Used to return all placements found. */
+    // Used to return all placements found. */
     placements_type placements_;
-    /** Bounding box of all texts placed. */
+    // Bounding box of all texts placed. */
     box2d<double> extents_;
-    /** Collect a bounding box of all texts placed. */
+    // Collect a bounding box of all texts placed. */
     bool collect_extents_;
 
-    /** Additional boxes to take into account when finding placement.
-     * Used for finding line placements where multiple placements are returned.
-     * Boxes are relative to starting point of current placement.
-     * Only used for point placements!
-     */
+    // Additional boxes to take into account when finding placement.
+    // Used for finding line placements where multiple placements are returned.
+    // Boxes are relative to starting point of current placement.
+    // Only used for point placements!
     std::vector<box2d<double> > additional_boxes_;
 };
 }
diff --git a/include/mapnik/processed_text.hpp b/include/mapnik/processed_text.hpp
index 581742520..5219a6785 100644
--- a/include/mapnik/processed_text.hpp
+++ b/include/mapnik/processed_text.hpp
@@ -40,11 +40,10 @@ template <typename T> class face_manager;
 class MAPNIK_DECL processed_text : mapnik::noncopyable
 {
 public:
-    class processed_expression
+    struct processed_expression
     {
-    public:
-        processed_expression(char_properties const& properties, UnicodeString const& text) :
-            p(properties), str(text) {}
+        processed_expression(char_properties const& properties, UnicodeString const& text)
+            : p(properties), str(text) {}
         char_properties p;
         UnicodeString str;
     };
@@ -57,7 +56,7 @@ public:
     typedef std::list<processed_expression> expression_list;
     expression_list::const_iterator begin() const;
     expression_list::const_iterator end() const;
-    string_info &get_string_info();
+    string_info const& get_string_info();
 private:
     expression_list expr_list_;
     face_manager<freetype_engine> &font_manager_;
diff --git a/include/mapnik/symbolizer_helpers.hpp b/include/mapnik/symbolizer_helpers.hpp
index 4da83c360..479b02db9 100644
--- a/include/mapnik/symbolizer_helpers.hpp
+++ b/include/mapnik/symbolizer_helpers.hpp
@@ -30,7 +30,7 @@
 #include <mapnik/processed_text.hpp>
 
 //boost
-#include <boost/shared_ptr.hpp>
+#include <boost/scoped_ptr.hpp>
 
 // agg
 #include "agg_trans_affine.h"
@@ -65,34 +65,14 @@ public:
                            CoordTransform const& t,
                            FaceManagerT &font_manager,
                            DetectorT &detector,
-                           box2d<double> const& query_extent)
-        : sym_(sym),
-          feature_(feature),
-          prj_trans_(prj_trans),
-          t_(t),
-          font_manager_(font_manager),
-          detector_(detector),
-          dims_(0, 0, width, height),
-          query_extent_(query_extent),
-          text_(font_manager, scale_factor),
-          angle_(0.0),
-          placement_valid_(false),
-          points_on_line_(false),
-          finder_()
-    {
-        initialize_geometries();
-        if (!geometries_to_process_.size()) return;
-        placement_ = sym_.get_placement_options()->get_placement_info(scale_factor);
-        next_placement();
-        initialize_points();
-    }
+                           box2d<double> const& query_extent);
 
-    /** Return next placement.
-     * If no more placements are found returns null pointer.
-     */
+    ~text_symbolizer_helper();
+    // Return next placement.
+    // If no more placements are found returns null pointer.
     bool next();
 
-    /** Get current placement. next() has to be called before! */
+    // Get current placement. next() has to be called before!
     placements_type const& placements() const;
 protected:
     bool next_point_placement();
@@ -113,28 +93,26 @@ protected:
     box2d<double> const& query_extent_;
     //Processing
     processed_text text_;
-    /* Using list instead of vector, because we delete random elements and need iterators to stay valid. */
-    /** Remaining geometries to be processed. */
+    // Using list instead of vector, because we delete random elements and need iterators to stay valid.
+    // Remaining geometries to be processed.
     std::list<geometry_type*> geometries_to_process_;
-    /** Geometry currently being processed. */
+    // Geometry currently being processed.
     std::list<geometry_type*>::iterator geo_itr_;
-    /** Remaining points to be processed. */
+    // Remaining points to be processed.
     std::list<position> points_;
-    /** Point currently being processed. */
+    // Point currently being processed.
     std::list<position>::iterator point_itr_;
-    /** Text rotation. */
+    // Text rotation.
     double angle_;
-    /** Text + formatting. */
-    string_info *info_;
-    /** Did last call to next_placement return true? */
+    // Did last call to next_placement return true?
     bool placement_valid_;
-    /** Use point placement. Otherwise line placement is used. */
+    // Use point placement. Otherwise line placement is used.
     bool point_placement_;
-    /** Place text at points on a line instead of following the line (used for ShieldSymbolizer) .*/
+    // Place text at points on a line instead of following the line (used for ShieldSymbolizer).
     bool points_on_line_;
 
     text_placement_info_ptr placement_;
-    boost::shared_ptr<placement_finder<DetectorT> > finder_;
+    boost::scoped_ptr<placement_finder<DetectorT> > finder_;
 };
 
 template <typename FaceManagerT, typename DetectorT>
@@ -193,7 +171,6 @@ protected:
     using text_symbolizer_helper<FaceManagerT, DetectorT>::geometries_to_process_;
     using text_symbolizer_helper<FaceManagerT, DetectorT>::placement_;
     using text_symbolizer_helper<FaceManagerT, DetectorT>::next_placement;
-    using text_symbolizer_helper<FaceManagerT, DetectorT>::info_;
     using text_symbolizer_helper<FaceManagerT, DetectorT>::geo_itr_;
     using text_symbolizer_helper<FaceManagerT, DetectorT>::point_itr_;
     using text_symbolizer_helper<FaceManagerT, DetectorT>::points_;
diff --git a/src/processed_text.cpp b/src/processed_text.cpp
index 83db904c1..4d2064d7e 100644
--- a/src/processed_text.cpp
+++ b/src/processed_text.cpp
@@ -55,7 +55,7 @@ void processed_text::clear()
 }
 
 
-string_info &processed_text::get_string_info()
+string_info const& processed_text::get_string_info()
 {
     info_.clear(); //if this function is called twice invalid results are returned, so clear string_info first
     expression_list::iterator itr = expr_list_.begin();
diff --git a/src/symbolizer_helpers.cpp b/src/symbolizer_helpers.cpp
index 65c020c56..4d89b039c 100644
--- a/src/symbolizer_helpers.cpp
+++ b/src/symbolizer_helpers.cpp
@@ -39,6 +39,42 @@
 
 namespace mapnik {
 
+template <typename FaceManagerT, typename DetectorT>
+text_symbolizer_helper<FaceManagerT, DetectorT>::text_symbolizer_helper(text_symbolizer const& sym,
+                           feature_impl const& feature,
+                           proj_transform const& prj_trans,
+                           unsigned width,
+                           unsigned height,
+                           double scale_factor,
+                           CoordTransform const& t,
+                           FaceManagerT &font_manager,
+                           DetectorT &detector,
+                           box2d<double> const& query_extent)
+        : sym_(sym),
+          feature_(feature),
+          prj_trans_(prj_trans),
+          t_(t),
+          font_manager_(font_manager),
+          detector_(detector),
+          dims_(0, 0, width, height),
+          query_extent_(query_extent),
+          text_(font_manager, scale_factor),
+          angle_(0.0),
+          placement_valid_(false),
+          points_on_line_(false),
+          finder_(0)
+    {
+        initialize_geometries();
+        if (!geometries_to_process_.size()) return;
+        placement_ = sym_.get_placement_options()->get_placement_info(scale_factor);
+        next_placement();
+        initialize_points();
+    }
+
+template <typename FaceManagerT, typename DetectorT>
+text_symbolizer_helper<FaceManagerT, DetectorT>::~text_symbolizer_helper()
+{}
+
 template <typename FaceManagerT, typename DetectorT>
 bool text_symbolizer_helper<FaceManagerT, DetectorT>::next()
 {
@@ -283,7 +319,6 @@ bool text_symbolizer_helper<FaceManagerT, DetectorT>::next_placement()
         return false;
     }
     placement_->properties.process(text_, feature_);
-    info_ = &(text_.get_string_info());
     if (placement_->properties.orientation)
     {
         // https://github.com/mapnik/mapnik/issues/1352
@@ -295,10 +330,9 @@ bool text_symbolizer_helper<FaceManagerT, DetectorT>::next_placement()
         angle_ = 0.0;
     }
 
-
-    finder_ = boost::shared_ptr<placement_finder<DetectorT> >(new placement_finder<DetectorT>(feature_, *placement_, *info_, detector_, dims_));
-//    boost::make_shared<placement_finder<DetectorT> >(feature_, *placement_, *info_, detector_, dims_);
-
+    finder_.reset(new placement_finder<DetectorT>(feature_, *placement_,
+                                                  text_.get_string_info(),
+                                                  detector_, dims_));
     placement_valid_ = true;
     return true;
 }
@@ -470,4 +504,5 @@ agg::trans_affine const& shield_symbolizer_helper<FaceManagerT, DetectorT>::get_
 
 template class text_symbolizer_helper<face_manager<freetype_engine>, label_collision_detector4>;
 template class shield_symbolizer_helper<face_manager<freetype_engine>, label_collision_detector4>;
+template class mapnik::placement_finder<mapnik::label_collision_detector4>;
 } //namespace