Disable feature https://github.com/opencv/opencv_contrib/pull/1194 in case of implicit reshape mask

modules/dnn/src/layers/reshape_layer.cpp

@@ -55,7 +55,6 @@ static void computeShapeByReshapeMask(const MatShape &srcShape,
 {
     int srcShapeSize = (int)srcShape.size();
     int maskShapeSize = (int)maskShape.size();
-    int maskTotal = abs(total(maskShape));  // Mask might have negative ones.
 
     if (srcRange == Range::all())
         srcRange = Range(0, srcShapeSize);
@@ -66,8 +65,15 @@ static void computeShapeByReshapeMask(const MatShape &srcShape,
         srcRange.end = srcRange.end == INT_MAX ? srcShapeSize : srcRange.start + sz;
     }
 
-    if (maskTotal != 0)
+    bool explicitMask = !maskShape.empty();  // All mask values are positive.
+    for (int i = 0, n = maskShape.size(); i < n && explicitMask; ++i)
     {
+        explicitMask = maskShape[i] > 0;
+    }
+    // Working range of source shape is a range where area(src) == area(mask).
+    if (explicitMask)
+    {
+        int maskTotal = total(maskShape);
         for (int i = srcRange.start + 1; i < srcRange.end; ++i)
         {
             if (total(srcShape, i, srcRange.end) != maskTotal)

modules/dnn/test/test_layers.cpp

@@ -169,14 +169,20 @@ TEST(Layer_Test_MVN, Accuracy)
      testLayerUsingCaffeModels("layer_mvn");
 }
 
-TEST(Layer_Test_Reshape, squeeze)
+void testReshape(const MatShape& inputShape, const MatShape& targetShape,
+                 int axis = 0, int num_axes = -1, bool reorder_dims = false,
+                 MatShape mask = MatShape())
 {
     LayerParams params;
-    params.set("axis", 2);
-    params.set("num_axes", 1);
+    params.set("axis", axis);
+    params.set("num_axes", num_axes);
+    params.set("reorder_dims", reorder_dims);
+    if (!mask.empty())
+    {
+        params.set("dim", DictValue::arrayInt<int*>(&mask[0], mask.size()));
+    }
 
-    int sz[] = {4, 3, 1, 2};
-    Mat inp(4, sz, CV_32F);
+    Mat inp(inputShape.size(), &inputShape[0], CV_32F);
     std::vector<Mat> inpVec(1, inp);
     std::vector<Mat> outVec, intVec;
 
@@ -185,9 +191,23 @@ TEST(Layer_Test_Reshape, squeeze)
 
     Mat& out = outVec[0];
     MatShape shape(out.size.p, out.size.p + out.dims);
-    int sh0[] = {4, 3, 2};
-    MatShape shape0(sh0, sh0+3);
-    EXPECT_EQ(shape, shape0);
+    EXPECT_EQ(shape, targetShape);
+}
+
+TEST(Layer_Test_Reshape, Accuracy)
+{
+    {
+        int inp[] = {4, 3, 1, 2};
+        int out[] = {4, 3, 2};
+        testReshape(MatShape(inp, inp + 4), MatShape(out, out + 3), 2, 1);
+    }
+    {
+        int inp[] = {1, 128, 4, 4};
+        int out[] = {1, 2048};
+        int mask[] = {-1, 2048};
+        testReshape(MatShape(inp, inp + 4), MatShape(out, out + 2), 0, -1, true,
+                    MatShape(mask, mask + 2));
+    }
 }
 
 TEST(Layer_Test_BatchNorm, Accuracy)