diff --git a/core/imagelib/warp.py b/core/imagelib/warp.py
index af77579..37a622e 100644
--- a/core/imagelib/warp.py
+++ b/core/imagelib/warp.py
@@ -143,7 +143,7 @@ def gen_warp_params (w, flip=False, rotation_range=[-10,10], scale_range=[-0.5,
     ################
     
     #random transform
-    random_transform_mat = cv2.getRotationMatrix2D((w // 2, w // 2), rotation, scale)
+    random_transform_mat = cv2.getRotationMatrix2D((int(w // 2), int(w // 2)), rotation, scale)
     random_transform_mat[:, 2] += (tx*w, ty*w)
 
     params = dict()
@@ -178,4 +178,4 @@ def warp_by_params (params, img, can_warp, can_transform, can_flip, border_repli
         img = img[...,None]
     if can_flip and params['flip']:
         img = img[:,::-1,...]
-    return img
\ No newline at end of file
+    return img
diff --git a/core/leras/device.py b/core/leras/device.py
index a2ba371..45a699e 100644
--- a/core/leras/device.py
+++ b/core/leras/device.py
@@ -46,7 +46,7 @@ class Devices(object):
         idx_mem = 0
         for device in self.devices:
             mem = device.total_mem
-            if mem > idx_mem:
+            if mem >= idx_mem:
                 result = device
                 idx_mem = mem
         return result
@@ -56,7 +56,7 @@ class Devices(object):
         idx_mem = sys.maxsize
         for device in self.devices:
             mem = device.total_mem
-            if mem < idx_mem:
+            if mem <= idx_mem:
                 result = device
                 idx_mem = mem
         return result
@@ -270,4 +270,4 @@ class Devices(object):
             os.environ[f'NN_DEVICE_{i}_TOTAL_MEM'] = str(device['total_mem'])
             os.environ[f'NN_DEVICE_{i}_FREE_MEM'] = str(device['free_mem'])
             os.environ[f'NN_DEVICE_{i}_CC'] = str(device['cc'])
-"""
\ No newline at end of file
+"""
diff --git a/core/leras/nn.py b/core/leras/nn.py
index f392aaf..29c6a00 100644
--- a/core/leras/nn.py
+++ b/core/leras/nn.py
@@ -112,6 +112,7 @@ class nn():
                 
             config.gpu_options.force_gpu_compatible = True
             config.gpu_options.allow_growth = True
+            config.allow_soft_placement = True
             nn.tf_sess_config = config
             
         if nn.tf_sess is None: