import cv2
import numpy as np
from PIL import Image
from numpy import asarray
import potrace
color = 65280
camera = cv2.VideoCapture(0)
camera.set(cv2.CAP_PROP_FRAME_WIDTH, 160)
camera.set(cv2.CAP_PROP_FRAME_HEIGHT, 120)
camera.set(cv2.CAP_PROP_FPS, 5)
print("camera FPS:{} height:{} width:{}".format(camera.get(cv2.CAP_PROP_FPS), camera.get(cv2.CAP_PROP_FRAME_WIDTH), camera.get(cv2.CAP_PROP_FRAME_HEIGHT)))
while(camera.isOpened()):
    pl = []
    ret, frame = camera.read()
    if ret==True:
        gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
        cv2.Canny(gray, 100,120 )
        (thresh, gray) = cv2.threshold(gray, 127, 255, cv2.THRESH_BINARY)
        nb = cv2.cvtColor(asarray(gray), cv2.COLOR_RGB2BGR)
        image = Image.fromarray(nb).convert("1")
        image.save( "/tmp/cv.png")
        bmp = potrace.Bitmap( asarray( image ) )
        # Trace the bitmap to a path
        path= bmp.trace(turdsize=16,alphamax=0.0, opticurve=0, opttolerance=1.0)
        # Iterate over path curves
        for curve in path:
            start = curve.start_point
            pl.append([start[0],start[1],0])
            pl.append([start[0],start[1],color])
            for segment in curve:
                end_point_x, end_point_y = segment.end_point
                if segment.is_corner:
                    #c_x, c_y = segment.c
                    pass
                else:
                    c1_x, c1_y = segment.c1
                    x, y = segment.c2
                    pl.append([x,y,color])
            pl.append([start[0],start[1],0])
            ret, frame = camera.read()
            #print(len(pl), flush = True)
        print(pl, flush = True)
    else:
        break

# Release everything if job is finished
camera.release()