#!/usr/local/bin/python

#
# hello.light.45.py
#
# receive and display light level
#
# Neil Gershenfeld
# CBA MIT 10/24/07
#
# (c) Massachusetts Institute of Technology 2007
# Permission granted for experimental and personal use;
# license for commercial sale available from MIT
#
# Modified by Inna Koyrakh
#

from Tkinter import *
import serial
import random
import Image
import ImageTk


#
# Filtering variables
#
WINDOW = 600
eps = 0.1
#saveflag = 0
#
# Usable sensor values
#
filter = 0.0
minVal = 2000.0
maxVal = 1.0
R = 100
#
# Open photo and extract its dimensions
#
imageFile = 'C:\\Documents and Settings\\Inna\\Desktop\\How to make (almost) anything\\Software\\photo2_small.jpg'
im1 = Image.open(imageFile)
im2 = im1
xdim, ydim = im1.size
#
# Canvas dimensions
#
cMin_x = 0
cMin_y = 0
cMax_x = 0.5*xdim
cMax_y = 0.5*ydim
#
# Canvas center
#
center_x = 0.5*(cMin_x+cMax_x)
center_y = 0.5*(cMin_y+cMax_y)



#
# open serial port
#
ser = serial.Serial('COM13',9600)
ser.setDTR()



def idle(parent,canvas):
   global minVal, maxVal, cMax_x, cMax_y, filter, eps, imageFile, im1, im2, im3 #saveflag
   #
   # idle routine
   #
   byte2 = 0
   byte3 = 0
   byte4 = 0
   ser.flush()
   while 1:
      #
      # find framing 
      #
      byte1 = byte2
      byte2 = byte3
      byte3 = byte4
      byte4 = ord(ser.read())
      if ((byte1 == 1) & (byte2 == 2) & (byte3 == 3) & (byte4 == 4)):
         break
   low = ord(ser.read())
   high = ord(ser.read())
   value = 256*high + low
   filter = (1-eps)*filter + eps*value
   #
   # learn current working range of sensor
   #
   if filter <= minVal:
      minVal = filter
   if filter >= maxVal:
      maxVal = filter

   #
   # GUI parameters
   #
   # set a max width and height
   #
   if (maxVal-minVal) > 0:
      rangeLight = int(round(maxVal-minVal))
   if (maxVal-minVal) <= 0:
      rangeLight = 1

   ratio = (filter-minVal)/rangeLight
   width = 1*xdim
   height = 1*ydim
   x = int(round(ratio*width))
   y = int(round(ratio*height))
   print x, y
   im2 = im1.resize((x,y), Image.NEAREST)
   im3 = ImageTk.PhotoImage(im2)
   canvas.create_image(0.5*cMax_x, 0.5*cMax_y, image=im3)
   canvas.update()
   parent.after_idle(idle,parent,canvas)



#
# set up GUI
#
#
# Set up master
#
master = Tk()
master.title('PhotoZoomer.py (q to exit)')
master.bind('q','exit')
#
# Initialize canvas
#
canvas = Canvas(master, width=cMax_x, height=cMax_y, background='white')
canvas.pack()
#
# start idle loop
#
master.after(100,idle,master,canvas) # ms allowed for startup
master.mainloop()