diff --git a/samplelib/SampleProcessor.py b/samplelib/SampleProcessor.py
index c445972..1fd5472 100644
--- a/samplelib/SampleProcessor.py
+++ b/samplelib/SampleProcessor.py
@@ -265,6 +265,53 @@ class SampleProcessor(object):
                             img_s = np.clip (img_s + (rnd_state.random()-0.5)*a, 0, 1 )
                             img_v = np.clip (img_v + (rnd_state.random()-0.5)*a, 0, 1 )
                             img = np.clip( cv2.cvtColor(cv2.merge([img_h, img_s, img_v]), cv2.COLOR_HSV2BGR) , 0, 1 )
+                        
+                        random_shadow_amount = 1
+                        if random_shadow_amount != 0 and rnd_state.random() < 0.5:
+                            high_ratio=(1,2)
+                            low_ratio=(0.01, 0.5)
+                            left_low_ratio=(0.4,0.6)
+                            left_high_ratio=(0,0.2)
+                            right_low_ratio=(0.4,0.6)
+                            right_high_ratio = (0,0.2)
+
+                            #check
+                            img = np.clip(img*255, 0, 255).astype(np.uint8)
+
+                            w, h, _= img.shape
+
+                            high_bright_factor = rnd_state.uniform(high_ratio[0], high_ratio[1])
+                            low_bright_factor = rnd_state.uniform(low_ratio[0], low_ratio[1])
+
+                            left_low_factor = rnd_state.uniform(left_low_ratio[0]*h, left_low_ratio[1]*h)
+                            left_high_factor = rnd_state.uniform(left_high_ratio[0]*h, left_high_ratio[1]*h)
+                            right_low_factor = rnd_state.uniform(right_low_ratio[0]*h, right_low_ratio[1]*h)
+                            right_high_factor = rnd_state.uniform(right_high_ratio[0]*h, right_high_ratio[1]*h)
+
+                            tl = (0, left_high_factor)
+                            bl = (0, left_high_factor+left_low_factor)
+
+                            tr = (w, right_high_factor)
+                            br = (w, right_high_factor+right_low_factor)
+
+                            contour = np.array([tl, tr, br, bl], dtype=np.int32)
+
+                            mask = np.zeros(img.shape, dtype=img.dtype)
+                            cv2.fillPoly(mask,[contour],(255,255,255))
+                            mask = cv2.cvtColor(mask, cv2.COLOR_BGR2GRAY)
+                            inverted_mask = cv2.bitwise_not(mask)
+
+                            hsv = cv2.cvtColor(img, cv2.COLOR_BGR2HSV)
+                            hsv[..., 2] = cv2.multiply(hsv[..., 2], high_bright_factor)
+                            high_brightness = cv2.cvtColor(hsv, cv2.COLOR_HSV2BGR)
+                            hsv[..., 2] = cv2.multiply(hsv[..., 2], low_bright_factor)
+                            low_brightness = cv2.cvtColor(hsv, cv2.COLOR_HSV2BGR)
+
+                            for i in range(3):
+                                img[:, :, i] = img[:, :, i] *(mask/255) + high_brightness[:, :, i] *(1-mask/255)
+                                img[:, :, i] = img[:, :, i] *(inverted_mask/255) + low_brightness[:, :, i] *(1-inverted_mask/255)
+                                
+                            img = np.clip(img/255.0, 0, 1).astype(np.float32)
 
                         img  = imagelib.warp_by_params (warp_params, img,  warp, transform, can_flip=True, border_replicate=border_replicate)
                         img = np.clip(img.astype(np.float32), 0, 1)