full_object_detection: API Support for dpoint (#2183) (#3095)

- Add constructor accepting parts as std::vector<dpoint>
- Internally switch parts representation to std::vector<dpoint>
- Update serialization logic to version 2 to support dpoint
- Deprecate constructor that takes std::vector<point>

Author: Infinage

dlib/data_io/load_image_dataset.h

@@ -406,7 +406,7 @@ namespace dlib
                     }
                     else
                     {
-                        std::vector<point> partlist(parts_idx.size(), OBJECT_PART_NOT_PRESENT);
+                        std::vector<dpoint> partlist(parts_idx.size(), OBJECT_PART_NOT_PRESENT);
 
                         // populate partlist with all the parts present in this box.
                         const std::map<std::string,point>& parts = data.images[i].boxes[j].parts;

dlib/image_processing/full_object_detection.h

@@ -13,8 +13,8 @@ namespace dlib
 
 // ----------------------------------------------------------------------------------------
 
-    const static point OBJECT_PART_NOT_PRESENT(0x7FFFFFFF,
-                                                0x7FFFFFFF);
+    const static dpoint OBJECT_PART_NOT_PRESENT(0x7FFFFFFFFFFFF,
+                                                0x7FFFFFFFFFFFF);
 
 // ----------------------------------------------------------------------------------------
 
@@ -23,9 +23,15 @@ namespace dlib
     public:
         full_object_detection(
             const rectangle& rect_,
-            const std::vector<point>& parts_
+            const std::vector<dpoint>& parts_
         ) : rect(rect_), parts(parts_) {}
 
+        full_object_detection(
+            const rectangle& rect_,
+            const std::vector<point>& parts_
+        ) : rect(rect_), parts (parts_.begin(), parts_.end())
+        {}
+
         full_object_detection(){}
 
         explicit full_object_detection(
@@ -36,13 +42,13 @@ namespace dlib
         rectangle& get_rect() { return rect; }
         unsigned long num_parts() const { return parts.size(); }
 
-        const point& part(
+        const dpoint& part(
             unsigned long idx
         ) const 
         { 
             // make sure requires clause is not broken
             DLIB_ASSERT(idx < num_parts(),
-                "\t point full_object_detection::part()"
+                "\t dpoint full_object_detection::part()"
                 << "\n\t Invalid inputs were given to this function "
                 << "\n\t idx:         " << idx  
                 << "\n\t num_parts(): " << num_parts()  
@@ -51,13 +57,13 @@ namespace dlib
             return parts[idx]; 
         }
 
-        point& part(
+        dpoint& part(
             unsigned long idx
         )  
         { 
             // make sure requires clause is not broken
             DLIB_ASSERT(idx < num_parts(),
-                "\t point full_object_detection::part()"
+                "\t dpoint full_object_detection::part()"
                 << "\n\t Invalid inputs were given to this function "
                 << "\n\t idx:         " << idx  
                 << "\n\t num_parts(): " << num_parts()  
@@ -71,7 +77,7 @@ namespace dlib
             std::ostream& out
         )
         {
-            int version = 1;
+            int version = 2;
             serialize(version, out);
             serialize(item.rect, out);
             serialize(item.parts, out);
@@ -84,11 +90,23 @@ namespace dlib
         {
             int version = 0;
             deserialize(version, in);
-            if (version != 1)
+
+            if (version != 1 && version != 2)
                 throw serialization_error("Unexpected version encountered while deserializing dlib::full_object_detection.");
 
             deserialize(item.rect, in);
-            deserialize(item.parts, in);
+
+            // Legacy support: read vector<point, 2> and cast to vector<dpoint, 2>
+            if (version == 1) {
+                std::vector<point> legacy_parts;
+                deserialize(legacy_parts, in);
+                item.parts = std::vector<dpoint>(legacy_parts.begin(), legacy_parts.end());
+            }
+
+            else { // version 2 - deserialize into vector<dpoint, 2>
+                deserialize(item.parts, in);
+            }
+
         }
 
         bool operator==(
@@ -109,7 +127,7 @@ namespace dlib
 
     private:
         rectangle rect;
-        std::vector<point> parts;  
+        std::vector<dpoint> parts;  
     };
 
 // ----------------------------------------------------------------------------------------

dlib/image_processing/full_object_detection_abstract.h

@@ -11,9 +11,9 @@ namespace dlib
 {
 
 // ----------------------------------------------------------------------------------------
-
-    const static point OBJECT_PART_NOT_PRESENT(0x7FFFFFFF,
-                                               0x7FFFFFFF);
+    
+    const static dpoint OBJECT_PART_NOT_PRESENT(0x7FFFFFFFFFFFF,
+                                                0x7FFFFFFFFFFFF);
 
 // ----------------------------------------------------------------------------------------
 
@@ -29,7 +29,7 @@ namespace dlib
 
         full_object_detection(
             const rectangle& rect,
-            const std::vector<point>& parts
+            const std::vector<dpoint>& parts
         );
         /*!
             ensures
@@ -39,6 +39,16 @@ namespace dlib
                     - part(i) == parts[i]
         !*/
 
+        full_object_detection(
+            const rectangle& rect_,
+            const std::vector<point>& parts_
+        );
+        /*!
+            ensures
+                - #get_rect() == rect
+                - #num_parts() == parts.size()
+        !*/
+
         full_object_detection(
         );
         /*!
@@ -79,7 +89,7 @@ namespace dlib
                 - returns the number of parts in this object.  
         !*/
 
-        const point& part(
+        const dpoint& part(
             unsigned long idx
         ) const; 
         /*!
@@ -92,7 +102,7 @@ namespace dlib
                   This is useful for modeling object parts that are not always observed.
         !*/
 
-        point& part(
+        dpoint& part(
             unsigned long idx
         ); 
         /*!

dlib/image_processing/scan_image_pyramid.h

@@ -874,7 +874,7 @@ namespace dlib
         // convert into feature space.
         object_box = object_box.intersect(get_rect(feats[best_level]));
 
-        std::vector<point> movable_parts;
+        std::vector<dpoint> movable_parts;
         movable_parts.reserve(get_num_movable_components_per_detection_template());
         for (unsigned long i = 0; i < get_num_movable_components_per_detection_template(); ++i)
         {

dlib/image_transforms/interpolation.h

@@ -1125,7 +1125,7 @@ namespace dlib
             const full_object_detection& obj
         )
         {
-            std::vector<point> parts; 
+            std::vector<dpoint> parts; 
             parts.reserve(obj.num_parts());
             for (unsigned long i = 0; i < obj.num_parts(); ++i)
             {

dlib/test/object_detector.cpp

@@ -296,7 +296,7 @@ namespace
         std::vector<full_object_detection> temp;
 
         rectangle rect = centered_rect(point(100,100), 70,71);
-        std::vector<point> movable_parts;
+        std::vector<dpoint> movable_parts;
         movable_parts.push_back(shrink_rect(rect,shrink).tl_corner());
         movable_parts.push_back(shrink_rect(rect,shrink).tr_corner());
         movable_parts.push_back(shrink_rect(rect,shrink).bl_corner());