################################################################################################### 
# Demonstrate creation of an image filters and new source based on filter.
# Also demonstrate creation of image histogram and use of overlays.
################################################################################################### 


import ch.psi.pshell.imaging.Filter as Filter
from ch.psi.pshell.imaging.Utils import *
from ch.psi.pshell.imaging.Overlays import *
import ch.psi.pshell.imaging.Pen as Pen

last = None
class MyFilter(Filter):
    def process(self, image, data):
        global last
        image = grayscale(image)        
        i=None
        if last is not None:
            i = sub(image,last, False)
            i = rescale(i,100.0, 0, True)
            i = add(i, last, True)
            i = rescale(i,10.0, 0, True)
        last = image        
        return i

def translate2(image, minV, maxV,inPlace):
        range = float(maxV - minV)
        scale = (255.0 / range) if (range > 0) else  1.0
        offset = -minV
        return rescale(image, scale,offset, inPlace)
    
    
class MyFilter2(Filter):
    def process(self, image, data):
        image = grayscale(image)        
        image = translate(image, 100, 200, True)
        #image = rescale(image, 1.0, 200.0, False)
        return image
        

#Setting the filter to a source
img.setFilter(MyFilter2())