diff --git a/sdk/plugins/compare.cpp b/sdk/plugins/compare.cpp
index 62b52d5..5deb254 100644
--- a/sdk/plugins/compare.cpp
+++ b/sdk/plugins/compare.cpp
@@ -42,7 +42,7 @@ public:
                   INF,
                   L1,
                   L2,
-                  CosineSimilarity };
+                  Cosine };
 
 private:
     BR_PROPERTY(Metric, metric, L2)
@@ -76,8 +76,8 @@ private:
           case L2:
             result = norm(a, b, NORM_L2);
             break;
-          case CosineSimilarity:
-            result = cosineSimilarity(a, b);
+          case Cosine:
+            result = cosine(a, b);
             break;
           default:
             qFatal("Invalid metric");
@@ -89,33 +89,29 @@ private:
         return -log(result+1);
     }
 
-    static float cosineSimilarity(const Mat &a, const Mat &b)
+    static float cosine(const Mat &a, const Mat &b)
     {
-        assert((a.type() == CV_32FC1) && (b.type() == CV_32FC1));
-        assert((a.rows == b.rows) && (a.cols == b.cols));
-
-        float denom = 0;
-        float tnum = 0;
-        float qnum = 0;
+        float dot = 0;
+        float magA = 0;
+        float magB = 0;
 
         for (int row=0; row<a.rows; row++) {
             for (int col=0; col<a.cols; col++) {
-                float target = a.at<float>(row,col);
-                float query = b.at<float>(row,col);
+                const float target = a.at<float>(row,col);
+                const float query = b.at<float>(row,col);
 
-                denom += target * query;
-                tnum += target * target;
-                qnum += query * query;
+                dot += target * query;
+                magA += target * target;
+                magB += query * query;
             }
         }
 
-        return denom / (sqrt(tnum)*sqrt(qnum));
+        return dot / (sqrt(magA)*sqrt(magB));
     }
 };
 
 BR_REGISTER(Distance, Dist)
 
-
 /*!
  * \ingroup distances
  * \brief Fast 8-bit L1 distance
diff --git a/sdk/plugins/regions.cpp b/sdk/plugins/regions.cpp
index 9d9086e..561fc74 100644
--- a/sdk/plugins/regions.cpp
+++ b/sdk/plugins/regions.cpp
@@ -79,23 +79,29 @@ BR_REGISTER(Transform, ByRow)
 class Cat : public UntrainableMetaTransform
 {
     Q_OBJECT
+    Q_PROPERTY(int partitions READ get_partitions WRITE set_partitions RESET reset_partitions)
+    BR_PROPERTY(int, partitions, 1)
 
     void project(const Template &src, Template &dst) const
     {
-        int vals = 0;
-        foreach (const cv::Mat &m, src)
-            vals += m.total() * m.channels();
-
-        Mat cat(1, (int)vals, CV_32FC1);
-        int offset = 0;
-        foreach (const cv::Mat &m, src) {
-            size_t size = m.total() * m.elemSize();
-            memcpy(&cat.data[offset], m.ptr(), size);
-            offset += size;
-        }
-
         dst.file = src.file;
-        dst = cat;
+
+        if (src.size() % partitions != 0)
+            qFatal("Cat %d partitions does not evenly divide %d matrices.", partitions, src.size());
+        QVector<int> sizes(partitions, 0);
+        for (int i=0; i<src.size(); i++)
+            sizes[i%partitions] += src[i].total() * src[i].channels();
+
+        foreach (int size, sizes)
+            dst.append(Mat(1, size, CV_32FC1));
+
+        QVector<int> offsets(partitions, 0);
+        for (int i=0; i<src.size(); i++) {
+            size_t size = src[i].total() * src[i].elemSize();
+            int j = i%partitions;
+            memcpy(&dst[j].data[offsets[j]], src[i].ptr(), size);
+            offsets[j] += size;
+        }
     }
 };
 
diff --git a/share/openbr/doc b/share/openbr/doc
index 1031e9e..19d116e 160000
--- a/share/openbr/doc
+++ b/share/openbr/doc
@@ -1 +1 @@
-Subproject commit 1031e9e416427f5dd8e9f4e7ff4dd74632626c22
+Subproject commit 19d116e16c35c55691e68ff137a48beb1f8ebf64
diff --git a/share/openbr/openbr.bib b/share/openbr/openbr.bib
index 81ff7bc..c3ef079 100644
--- a/share/openbr/openbr.bib
+++ b/share/openbr/openbr.bib
@@ -24,7 +24,7 @@
 @misc{mburge,
 	Author = {Dr. Mark J. Burge},
 	Howpublished = {https://github.com/mburge},
-	Title = {mburge at ieee.org}}
+	Title = {mburge at gmail.com}}
 
 @misc{bklare,
 	Author = {Dr. Brendan F. Klare},