#!/usr/bin/env python
# coding: utf-8

# # Image Filters
# ## 2015/4/22 信號與系統課堂DEMO

# In[1]:


get_ipython().run_line_magic('matplotlib', 'inline')
from scipy.misc import lena
import numpy as np
import matplotlib.pyplot as plt
ima = lena()
plt.imshow(ima, cmap=plt.cm.gray)


# In[2]:


print ima.shape


# In[3]:


ima2=ima.copy()
for xx in range(512):
    for yy in range(1,511):
        ima2[xx,yy]=(ima[xx,yy-1]+ima[xx,yy]+ima[xx,yy+1])/3.0
        
plt.imshow(ima2,cmap=plt.cm.gray)


# In[4]:


ima2=ima.copy()
for xx in range(512):
    for yy in range(511):
        ima2[xx,yy]=abs(ima[xx,yy]-ima[xx,yy+1])
        
plt.imshow(ima2,cmap=plt.cm.gray)
plt.clim(0,10)
plt.colorbar()


# In[5]:


plt.figure(figsize=(15,5), dpi=300)
plt.subplot(121)
plt.imshow(ima, cmap=plt.cm.gray)

for kk in range(10):
    for xx in range(510):
        for yy in range(1,511):
            ima2[xx,yy]=(ima[xx,yy-1]+ima[xx,yy]+ima[xx,yy+1])/3.0
    ima=ima2.copy()
    

plt.subplot(122)
plt.imshow(ima2,cmap=plt.cm.gray)


# In[ ]: