opencv: GPU not working with DNN_BACKEND_OPENCV

System information (version)

• OpenCV => 4.1.2
• Operating System / Platform => Windows 64 Bit
• Compiler => Visual Studio 2017
• Cuda => 10.2

Hello !

I use darknet Yolo for object detection and it works very well. Unfortunately with the CPU it’s very slow! I can make Darknet.exe work on the GPU but not in python.

net = cv2.dnn.readNet("dark/yolov3.weights", "dark/yolov3.cfg")
classes = []
with open("dark/coco.names", "r") as f:
    classes = [line.strip() for line in f.readlines()]
layer_names = net.getLayerNames()
output_layers = [layer_names[i[0] - 1] for i in net.getUnconnectedOutLayers()]
colors = np.random.uniform(0, 255, size=(len(classes), 3))

net.setPreferableBackend(cv2.dnn.DNN_BACKEND_OPENCV)
net.setPreferableTarget(cv2.dnn.DNN_TARGET_OPENCL_FP16)

Output :

OpenCV(ocl4dnn): consider to specify kernel configuration cache directory via OPENCV_OCL4DNN_CONFIG_PATH parameter. OpenCL program build log: dnn/dummy Status -11: CL_BUILD_PROGRAM_FAILURE -cl-no-subgroup-ifp Error in processing command line: Don’t understand command line argument “-cl-no-subgroup-ifp”!

The execution doesn’t crash but it’s the CPU that does the calculations.

Can u help ? Thx !