diff --git a/utils/datasets.py b/utils/datasets.py
index cfcb19b1..5ec67a44 100755
--- a/utils/datasets.py
+++ b/utils/datasets.py
@@ -15,7 +15,9 @@ from utils.utils import xyxy2xywh
 class load_images():  # for inference
     def __init__(self, path, batch_size=1, img_size=416):
         if os.path.isdir(path):
+            image_format = ['.jpg', '.jpeg', '.png', '.tif']
             self.files = sorted(glob.glob('%s/*.*' % path))
+            self.files = list(filter(lambda x: os.path.splitext(x)[1].lower() in image_format, self.files))
         elif os.path.isfile(path):
             self.files = [path]
 
diff --git a/utils/onnx2coreml.py b/utils/onnx2coreml.py
index 2e18a763..4c00c20a 100644
--- a/utils/onnx2coreml.py
+++ b/utils/onnx2coreml.py
@@ -42,8 +42,11 @@ def main():
         spec = coremltools.utils.convert_neural_network_spec_weights_to_fp16(spec)
         yolov3_model = coremltools.models.MLModel(spec)
 
+        name_out0 = spec.description.output[0].name
+        name_out1 = spec.description.output[1].name
+
         num_classes = 80
-        num_anchors = 507
+        num_anchors = 507  # 507 for yolov3-tiny,
         spec.description.output[0].type.multiArrayType.shape.append(num_anchors)
         spec.description.output[0].type.multiArrayType.shape.append(num_classes)
         # spec.description.output[0].type.multiArrayType.shape.append(1)
@@ -75,7 +78,7 @@ def main():
         from PIL import Image
         img = Image.open('../yolov3/data/samples/zidane_416.jpg')
         out = yolov3_model.predict({'0': img}, useCPUOnly=True)
-        print(out['148'].shape, out['150'].shape)
+        print(out[name_out0].shape, out[name_out1].shape)
 
         # 3. Create NMS protobuf
         import numpy as np
@@ -107,15 +110,15 @@ def main():
             del ma_type.shape[:]
 
         nms = nms_spec.nonMaximumSuppression
-        nms.confidenceInputFeatureName = '148'  # 1x507x80
-        nms.coordinatesInputFeatureName = '150'  # 1x507x4
+        nms.confidenceInputFeatureName = name_out0  # 1x507x80
+        nms.coordinatesInputFeatureName = name_out1  # 1x507x4
         nms.confidenceOutputFeatureName = 'confidence'
         nms.coordinatesOutputFeatureName = 'coordinates'
         nms.iouThresholdInputFeatureName = 'iouThreshold'
         nms.confidenceThresholdInputFeatureName = 'confidenceThreshold'
 
-        nms.iouThreshold = 0.6
-        nms.confidenceThreshold = 0.3
+        nms.iouThreshold = 0.4
+        nms.confidenceThreshold = 0.5
         nms.pickTop.perClass = True
 
         labels = np.loadtxt('../yolov3/data/coco.names', dtype=str, delimiter='\n')