Enabled OpenCL in OpenCV (albumentations-team#24)

* Enabled OpenCL in OpenCV

* Added comment about OpenCL block to README

* Added comment about OpenCL block to README

Author: ternaus

README.md

@@ -129,5 +129,15 @@ Alternatively, you can start a web server that rebuilds the documentation
 automatically when a change is detected by running `make livehtml`
 
 
+## Comments
+In some systems, in the multiple GPU regime PyTorch may deadlock the DataLoader if OpenCV was compiled with OpenCL optimizations. Adding the following two lines before the library import may help. For more details [https://github.com/pytorch/pytorch/issues/1355](https://github.com/pytorch/pytorch/issues/1355) 
+
+
+
+```python
+cv2.setNumThreads(0)	
+cv2.ocl.setUseOpenCL(False)
+```
+
 ### Thanks:
 Special thanks to [@creafz](https://github.com/creafz) for refactoring, documentation, tests, CI and benchmarks. Awesome work!

albumentations/augmentations/functional.py

@@ -3,9 +3,6 @@
 
 import cv2
 
-cv2.setNumThreads(0)
-cv2.ocl.setUseOpenCL(False)
-
 import numpy as np
 from scipy.ndimage.filters import gaussian_filter
 

albumentations/augmentations/transforms.py

@@ -2,9 +2,6 @@
 
 import cv2
 
-cv2.setNumThreads(0)
-cv2.ocl.setUseOpenCL(False)
-
 import numpy as np
 
 from ..core.transforms_interface import to_tuple, DualTransform, ImageOnlyTransform

albumentations/core/transforms_interface.py

@@ -1,7 +1,5 @@
 import numpy as np
 import cv2
-cv2.setNumThreads(0)
-cv2.ocl.setUseOpenCL(False)
 
 __all__ = ['to_tuple', 'BasicTransform', 'DualTransform', 'ImageOnlyTransform']