Update app.py

app.py

@@ -29,8 +29,10 @@ def imGreyAlpha(im):
             alpha = px[i, j] # 获取灰度作为alpha值
             if alpha == 0:
                 draw.point((i,j), fill=(0,0,0,0))
+            # elif alpha == 255:
+            #      draw.point((i,j), fill=(0,0,0,255))
             else:
-                draw.point((i, j), fill=(0, 0, 0, alpha)) # 填充像素点
+                draw.point((i, j), fill=(255, 255, 255, 255 -alpha)) # 填充像素点
 
     
     return im2 # 返回图像