diff --git a/keras_retinanet/bin/evaluate_coco.py b/keras_retinanet/bin/evaluate_coco.py
index e29db7a52..374c06eb4 100755
--- a/keras_retinanet/bin/evaluate_coco.py
+++ b/keras_retinanet/bin/evaluate_coco.py
@@ -75,9 +75,7 @@ def main(args=None):
     # create a generator for testing data
     test_generator = CocoGenerator(
         args.coco_path,
-        args.set,
-        image_min_side=800,
-        image_max_side=1333,
+        args.set
     )
 
     evaluate_coco(test_generator, model, args.score_threshold)
diff --git a/keras_retinanet/bin/train.py b/keras_retinanet/bin/train.py
index 03d3949af..1033793d0 100755
--- a/keras_retinanet/bin/train.py
+++ b/keras_retinanet/bin/train.py
@@ -158,17 +158,13 @@ def create_generators(args):
             args.coco_path,
             'train2017',
             transform_generator=transform_generator,
-            batch_size=args.batch_size,
-            image_min_side=800,
-            image_max_side=1333,
+            batch_size=args.batch_size
         )
 
         validation_generator = CocoGenerator(
             args.coco_path,
             'val2017',
-            batch_size=args.batch_size,
-            image_min_side=800,
-            image_max_side=1333,
+            batch_size=args.batch_size
         )
     elif args.dataset_type == 'pascal':
         train_generator = PascalVocGenerator(
diff --git a/keras_retinanet/preprocessing/generator.py b/keras_retinanet/preprocessing/generator.py
index 6916e53d0..ed37ddf25 100644
--- a/keras_retinanet/preprocessing/generator.py
+++ b/keras_retinanet/preprocessing/generator.py
@@ -40,8 +40,8 @@ def __init__(
         batch_size=1,
         group_method='ratio',  # one of 'none', 'random', 'ratio'
         shuffle_groups=True,
-        image_min_side=600,
-        image_max_side=1024,
+        image_min_side=800,
+        image_max_side=1333,
         transform_parameters=None,
     ):
         self.transform_generator  = transform_generator
diff --git a/keras_retinanet/utils/image.py b/keras_retinanet/utils/image.py
index a50490334..847a97ade 100644
--- a/keras_retinanet/utils/image.py
+++ b/keras_retinanet/utils/image.py
@@ -160,7 +160,7 @@ def apply_transform(matrix, image, params):
     return output
 
 
-def resize_image(img, min_side=600, max_side=1024):
+def resize_image(img, min_side=800, max_side=1333):
     (rows, cols, _) = img.shape
 
     smallest_side = min(rows, cols)