diff --git a/codes/data/LQGT_dataset.py b/codes/data/LQGT_dataset.py
index a13948a5..b8321963 100644
--- a/codes/data/LQGT_dataset.py
+++ b/codes/data/LQGT_dataset.py
@@ -5,7 +5,7 @@ import lmdb
 import torch
 import torch.utils.data as data
 import data.util as util
-from PIL import Image
+from PIL import Image, ImageOps
 from io import BytesIO
 import torchvision.transforms.functional as F
 
@@ -180,6 +180,9 @@ class LQGTDataset(data.Dataset):
             corruption_buffer.seek(0)
             img_LQ = Image.open(corruption_buffer)
 
+        if self.opt['grayscale']:
+            img_LQ = ImageOps.grayscale(img_LQ)
+
         img_GT = torch.from_numpy(np.ascontiguousarray(np.transpose(img_GT, (2, 0, 1)))).float()
         img_PIX = torch.from_numpy(np.ascontiguousarray(np.transpose(img_PIX, (2, 0, 1)))).float()
         img_LQ = F.to_tensor(img_LQ)