#!/opt/local/bin/python
# Script to play a video file in response to a button press event
# Pressing "x" or receiving an 'x' over the serial port starts video playback
# counter_dur defines for how long movie will play
# video loops until "ESC" is pressed
#
# uses the openCV highgui for the moment. wxpython or pyqt would be better, probably 
# to get rid of window decorations
# Armin Hinterwirth, June 2011
 
 
import cv
import time
import sys
import serial
 
curpos = 0
counter_dur = 1
counter_time = time.time() # initialize timer
 
# Arduino object that deals with serial communication:
class Arduino():
 
	def __init__(self):
		self.connected = 0
 
	def connect(self):	
		try:  
			serialport = "/dev/tty.usbserial-A7006xMg"
			# serialport needs to be set accordingly
			self.arduino = serial.Serial(serialport, 9600, timeout=0)
			self.connected = 1
			print 'Connected to Arduino'
 
		except:
			print "Failed to connect on /dev/tty.usbserial-A7006xMg"
			print '(Arduino not connected)'
			self.connected = 0
 
	def readSerial(self):
		if self.isConnected():
			cmd = self.arduino.read() #read one byte
			return cmd
		else:
			print("SerialRead unsuccessful")
 
	def isConnected(self):
		if self.connected == 1:
			return True
 
def counter_expired(counter_time):
	cur_time = time.time()
	# print "%.2f" % (cur_time - counter_time) # debug: print timer values
 
	if (cur_time - counter_time) > counter_dur:
		return True
 
def showMovieFrame(cam1,frames):
	frame = cv.QueryFrame(cam1)
	if (frame==None):
		sys.exit(2);
	curpos = int(cv.GetCaptureProperty(cam1, cv.CV_CAP_PROP_POS_FRAMES))
	# print "Frame: " + str(curpos)
	# show the image:
	cv.ShowImage("viewer", frame)
	# 'rewind' if end is reached:
	if (curpos > frames-2):
		cv.SetCaptureProperty(cam1,cv.CV_CAP_PROP_POS_FRAMES, 0)
 
 
def main():
 
	arduino = Arduino()
	arduino.connect()
	time.sleep(1) # give it some time
 
	cv.NamedWindow("viewer", 0)
	cv.MoveWindow("viewer", 300, -20 );
 
	cam1 = cv.CaptureFromFile('movingStripe.avi')
	# cam1 = cv.CaptureFromFile('grating.avi')
 
	# get first frame and display it:
	frame = cv.QueryFrame(cam1)
	if (frame == None):
		sys.exit(2)
 
	curpos = int(cv.GetCaptureProperty(cam1, cv.CV_CAP_PROP_POS_FRAMES))
	# print curpos
	cv.ShowImage("viewer", frame)
 
	frames = long(cv.GetCaptureProperty(cam1, cv.CV_CAP_PROP_FRAME_COUNT))	
	print "Movie length: " + str(frames) + " frames"
	outerloop = True # waiting for serial command
	innerloop = False # video playback loop
 
	while(outerloop):
		if arduino.isConnected():
			cmd = arduino.readSerial()
			if (cmd == None):
				print("no serial received")
 
			if (cmd == 'x'):
				counter_time = time.time() # set the timer
				innerloop = True			
 
		char = cv.WaitKey(1)
		# check which keys were pressed:
		if (char == 120):
			counter_time = time.time() # set the timer
			innerloop = True
		elif (char==102):
			showMovieFrame(cam1,frames)
		elif (char ==27):
			sys.exit(2)			
 
		while(innerloop):	
 
			showMovieFrame(cam1,frames)
 
			char = cv.WaitKey(1)	
			# end the program if esc button is pressed:
			if (char == 27):
				sys.exit(2)
 
			# get out of the loop if counter is expired:
			if counter_expired(counter_time):
				print("timer expired")
				innerloop = False
 
 
if __name__ == '__main__':
	main()

/* 
 * Button2Serial
 * 
 * Button press leads to serial command
 * Armin Hinterwirth, June 2011
 *
 */
 
const int buttonPin = 2;
const int ledPin = 13;
long time = 0;           // timer for button debouncing
long debounce = 200;     // debounce time for button in ms
byte buttonState = LOW;
 
void setup() {
  pinMode(buttonPin, INPUT); 
  pinMode(ledPin, OUTPUT);
  Serial.begin(9600);    // serial comm. for triggering     
}
 
void loop() {
  // read the switch state:
  buttonState = digitalRead(buttonPin);
  // turn ledPin high if button is pressed (button drops to low, then)
  if (buttonState == HIGH && (millis() - time) > debounce) {
    serialTalk();
    digitalWrite(ledPin, HIGH);  
    delay(200);
    digitalWrite(ledPin, LOW);
    time = millis();
  }
}
 
void serialTalk() {
  Serial.print("x");  // print an 'x' when button is pressed
}