Merge remote-tracking branch 'upstream/3.4' into merge-3.4

modules/dnn/src/dnn.cpp

@@ -2979,6 +2979,13 @@ String parseLayerParams(const String& name, const LayerParams& lp) {
 String Net::dump()
 {
     CV_Assert(!empty());
+
+    if (impl->netInputLayer->inputsData.empty())
+        CV_Error(Error::StsError, "Requested set input");
+
+    if (!impl->netWasAllocated)
+        impl->setUpNet();
+
     std::ostringstream out;
     std::map<int, LayerData>& map = impl->layers;
     int prefBackend = impl->preferableBackend;

modules/dnn/src/layers/slice_layer.cpp

@@ -61,6 +61,7 @@ public:
     {
         setParamsFrom(params);
         axis = params.get<int>("axis", 1);
+        num_split = params.get<int>("num_split", 0);
         if (params.has("slice_point"))
         {
             CV_Assert(!params.has("begin") && !params.has("size") && !params.has("end"));
@@ -141,9 +142,10 @@ public:
         else  // Divide input blob on equal parts by axis.
         {
             CV_Assert(0 <= axis && axis < inpShape.size());
-            CV_Assert(requiredOutputs > 0 && inpShape[axis] % requiredOutputs == 0);
-            inpShape[axis] /= requiredOutputs;
-            outputs.resize(requiredOutputs, inpShape);
+            int splits = num_split ? num_split : requiredOutputs;
+            CV_Assert(splits > 0 && inpShape[axis] % splits == 0);
+            inpShape[axis] /= splits;
+            outputs.resize(splits, inpShape);
         }
         return false;
     }

modules/dnn/src/tensorflow/tf_importer.cpp

@@ -1410,6 +1410,9 @@ void TFImporter::populateNet(Net dstNet)
                 axis = toNCHW(axis);
             layerParams.set("axis", axis);
 
+            if (hasLayerAttr(layer, "num_split"))
+                layerParams.set("num_split", getLayerAttr(layer, "num_split").i());
+
             int id = dstNet.addLayer(name, "Slice", layerParams);
             layer_id[name] = id;