OpenCV can load and use DNNs that have been trained in any of the following frameworks:
- Caffe (http://caffe.berkeleyvision.org/)
- TensorFlow (https://www.tensorflow.org/)
- Torch (http://torch.ch/)
- Darknet (https://pjreddie.com/darknet/)
- ONNX (https://onnx.ai/)
- DLDT (https://github.com/opencv/dldt/)