updated docs

docs/docs/imaging.xml

@@ -188,6 +188,7 @@
          <item>resize_image</item> 
          <item>flip_image_left_right</item> 
          <item>flip_image_up_down</item> 
+         <item>add_image_left_right_flips</item> 
       </section>
 
       <section>
@@ -1415,6 +1416,21 @@
          </description>
       </component>
 
+   <!-- ************************************************************************* -->
+
+      <component>
+         <name>add_image_left_right_flips</name>
+         <file>dlib/image_transforms.h</file>
+         <spec_file link="true">dlib/image_transforms/interpolation_abstract.h</spec_file>
+         <description>        
+            This routine takes a set of images and bounding boxes within those
+            images and doubles the size of the dataset by adding left/right
+            flipped copies of each image as well as the corresponding bounding
+            boxes.  Therefore, this function is useful if you are training and
+            object detector and your objects have a left/right symmetry.  
+         </description>
+      </component>
+
    <!-- ************************************************************************* -->
       
       <component>

docs/docs/term_index.xml

@@ -1226,6 +1226,7 @@
          <term file="imaging.html" name="rotate_image"            include="dlib/image_transforms.h"/>
          <term file="imaging.html" name="resize_image"            include="dlib/image_transforms.h"/>
          <term file="imaging.html" name="pyramid_up"              include="dlib/image_transforms.h"/>
+         <term file="imaging.html" name="add_image_left_right_flips" include="dlib/image_transforms.h"/>
          <term file="imaging.html" name="flip_image_left_right"   include="dlib/image_transforms.h"/>
          <term file="imaging.html" name="flip_image_up_down"      include="dlib/image_transforms.h"/>
          <term file="dlib/image_transforms/interpolation_abstract.h.html" name="black_background" include="dlib/image_transforms.h"/>