Ask Your Question

Revision history [back]

opencv code doesn't run on raspberry pi

hello, I have been working on gesture recognition using raspberry pi and opencv, I am able to run the following code on my linux and windows machines but not on the raspberry pi, note that I am able to run other scripts on the raspberry pi

import cv2 import numpy as np import math import imutils import time from collections import deque from imutils.video import VideoStream import argparse # construct the argument parse ap = argparse.ArgumentParser() ap.add_argument("-v", "--video", help="path to the (optional) video file") ap.add_argument("-b", "--buffer", type=int, default=32, help="max buffer size") args = vars(ap.parse_args())

cap = cv2.VideoCapture(0) pts = deque(maxlen=args["buffer"]) counter = 0 (dX, dY) = (0, 0)
while(1):

try:  #an error comes if it does not find anything in window as it cannot find contour of max area
      #therefore this try error statement

    ret, frame = cap.read()
    ret2, frame2 = cap.read()
    frame=cv2.flip(frame,1)
    frame2=cv2.flip(frame2,1)
    kernel = np.ones((3,3),np.uint8)
    frame2 = imutils.resize(frame2, width=600)
    blurred = cv2.GaussianBlur(frame2, (11, 11), 0)
    hsv2 = cv2.cvtColor(blurred, cv2.COLOR_BGR2HSV)



    #define region of interest
    roi=frame[100:300, 100:300]


    cv2.rectangle(frame,(50,50),(500,500),(0,255,0),0)    
    hsv = cv2.cvtColor(roi, cv2.COLOR_BGR2HSV)



# define range of skin color in HSV
    lower_skin = np.array([0,20,70], dtype=np.uint8)
    upper_skin = np.array([20,255,255], dtype=np.uint8)




 #extract skin colur imagw  
    mask = cv2.inRange(hsv, lower_skin, upper_skin)
    mask2 = cv2.inRange(hsv2, lower_skin, upper_skin)
    mask2 = cv2.erode(mask2, None, iterations=2)


     #extrapolate the hand to fill dark spots within
    mask = cv2.dilate(mask,kernel,iterations = 4)
    mask2 = cv2.dilate(mask2,None, iterations=2)
      #blur the image
    mask = cv2.GaussianBlur(mask,(5,5),100) 



      #find contours
    cnts,contours,hierarchy= cv2.findContours(mask,cv2.RETR_TREE,cv2.CHAIN_APPROX_SIMPLE)

      #find contour of max area(hand)
    cnt = max(contours, key = lambda x: cv2.contourArea(x))

      #approx the contour a little
    epsilon = 0.0005*cv2.arcLength(cnt,True)
    approx= cv2.approxPolyDP(cnt,epsilon,True)


       #make convex hull around hand
    hull = cv2.convexHull(cnt)

           #define area of hull and area of hand
    areahull = cv2.contourArea(hull)
    areacnt = cv2.contourArea(cnt)

          #find the percentage of area not covered by hand in convex hull
    arearatio=((areahull-areacnt)/areacnt)*100

      #find the defects in convex hull with respect to hand
    hull = cv2.convexHull(approx, returnPoints=False)
    defects = cv2.convexityDefects(approx, hull)

        # l = no. of defects
    l=0

    cnts2 = cv2.findContours(mask2.copy(), cv2.RETR_EXTERNAL,cv2.CHAIN_APPROX_SIMPLE)
    cnts2 = imutils.grab_contours(cnts2)
    center = None
    c = max(cnts2, key=cv2.contourArea)
    ((x, y), radius) = cv2.minEnclosingCircle(c)
    M = cv2.moments(c)
    center = (int(M["m10"] / M["m00"]), int(M["m01"] / M["m00"]))
    cv2.circle(frame, (int(x), int(y)),  10, [255,125,0], -1)
    pts.appendleft(center)

    for i in np.arange(1, len(pts)):

        if pts[i - 1] is None or pts[i] is None:

            continue


        if counter >= 5 and i == 1 and pts[-5] is not None:
            # compute the difference between the x and y
        # coordinates and re-initialize the direction
        # text variables
            dX = pts[-10][0] - pts[i][0]
            dY = pts[-10][1] - pts[i][1]

            print(areacnt)

    #code for finding no. of defects due to fingers
    for i in range(defects.shape[0]):
        s,e,f,d = defects[i,0]
        start = tuple(approx[s][0])
        end = tuple(approx[e][0])
        far = tuple(approx[f][0])
        pt= (100,180)


        # find length of all sides of triangle
        a = math.sqrt((end[0] - start[0])**2 + (end[1] - start[1])**2)
        b = math.sqrt((far[0] - start[0])**2 + (far[1] - start[1])**2)
        c = math.sqrt((end[0] - far[0])**2 + (end[1] - far[1])**2)
        s = (a+b+c)/2
        ar = math.sqrt(s*(s-a)*(s-b)*(s-c))

        #distance between point and convex hull
        d=(2*ar)/a

        # apply cosine rule here
        angle = math.acos((b**2 + c**2 - a**2)/(2*b*c)) * 57


        # ignore angles > 90 and ignore points very close to convex hull(they generally come due to noise)
        if angle <= 90 and d>30:
            l += 1
            cv2.circle(roi, far, 3, [255,0,0], -1)

        #draw lines around hand
        cv2.line(roi,start, end, [0,255,0], 2)


    l+=1

    #print corresponding gestures which are in their ranges
    font = cv2.FONT_HERSHEY_SIMPLEX
    if l==1:
        if areacnt<2000:
            cv2.putText(frame,'Put hand in the box',(0,50), font, 2, (0,0,255), 3, cv2.LINE_AA)
        else:
            if arearatio<12:
                cv2.putText(frame,'0',(0,50), font, 2, (0,0,255), 3, cv2.LINE_AA)
            elif arearatio<17.5:
                cv2.putText(frame,'Best of luck',(0,50), font, 2, (0,0,255), 3, cv2.LINE_AA)

            else:
                cv2.putText(frame,'1',(0,50), font, 2, (0,0,255), 3, cv2.LINE_AA)

    elif l==2:
        cv2.putText(frame,'2',(0,50), font, 2, (0,0,255), 3, cv2.LINE_AA)

    elif l==3:

          if arearatio<27:
                cv2.putText(frame,'3',(0,50), font, 2, (0,0,255), 3, cv2.LINE_AA)
          else:
                cv2.putText(frame,'ok',(0,50), font, 2, (0,0,255), 3, cv2.LINE_AA)

    elif l==4:
        cv2.putText(frame,'4',(0,50), font, 2, (0,0,255), 3, cv2.LINE_AA)

    elif l==5:
        cv2.putText(frame,'5',(0,50), font, 2, (0,0,255), 3, cv2.LINE_AA)

    elif l==6:
        cv2.putText(frame,'reposition',(0,50), font, 2, (0,0,255), 3, cv2.LINE_AA)

    else :
        cv2.putText(frame,'reposition',(10,50), font, 2, (0,0,255), 3, cv2.LINE_AA)


    #show the windows
    cv2.imshow('mask',mask)
    cv2.imshow('frame',frame)
    cv2.imshow('frame2',frame)
except:
    pass

counter += 1
k = cv2.waitKey(5) & 0xFF
if k == 27:
    break

cv2.destroyAllWindows() cap.release()

click to hide/show revision 2
None

updated 2020-03-14 07:46:46 -0600

berak gravatar image

opencv code doesn't run on raspberry pi

hello, I have been working on gesture recognition using raspberry pi and opencv, I am able to run the following code on my linux and windows machines but not on the raspberry pi, note that I am able to run other scripts on the raspberry pi

import cv2
import numpy as np
import math
import imutils
import time
from collections import deque
from imutils.video import VideoStream
import argparse
# construct the argument parse
ap = argparse.ArgumentParser()
ap.add_argument("-v", "--video",
help="path to the (optional) video file")
ap.add_argument("-b", "--buffer", type=int, default=32,
help="max buffer size")
args = vars(ap.parse_args())

vars(ap.parse_args()) cap = cv2.VideoCapture(0) pts = deque(maxlen=args["buffer"]) counter = 0 (dX, dY) = (0, 0)
while(1):


while(1):
try: #an error comes if it does not find anything in window as it cannot find contour of max area
 #therefore this try error statement
 ret, frame = cap.read()
 ret2, frame2 = cap.read()
 frame=cv2.flip(frame,1)
 frame2=cv2.flip(frame2,1)
 kernel = np.ones((3,3),np.uint8)
  frame2 = imutils.resize(frame2, width=600)
  blurred = cv2.GaussianBlur(frame2, (11, 11), 0)
 hsv2 = cv2.cvtColor(blurred, cv2.COLOR_BGR2HSV)
  #define region of interest
 roi=frame[100:300, 100:300]
 cv2.rectangle(frame,(50,50),(500,500),(0,255,0),0)
  hsv = cv2.cvtColor(roi, cv2.COLOR_BGR2HSV)
 # define range of skin color in HSV
 lower_skin = np.array([0,20,70], dtype=np.uint8)
 upper_skin = np.array([20,255,255], dtype=np.uint8)
  #extract skin colur imagw
 mask = cv2.inRange(hsv, lower_skin, upper_skin)
 mask2 = cv2.inRange(hsv2, lower_skin, upper_skin)
 mask2 = cv2.erode(mask2, None, iterations=2)
  #extrapolate the hand to fill dark spots within
 mask = cv2.dilate(mask,kernel,iterations = 4)
  mask2 = cv2.dilate(mask2,None, iterations=2)
  #blur the image
 mask = cv2.GaussianBlur(mask,(5,5),100)
  #find contours
 cnts,contours,hierarchy= cv2.findContours(mask,cv2.RETR_TREE,cv2.CHAIN_APPROX_SIMPLE)
  #find contour of max area(hand)
 cnt = max(contours, key = lambda x: cv2.contourArea(x))
  #approx the contour a little
 epsilon = 0.0005*cv2.arcLength(cnt,True)
  approx= cv2.approxPolyDP(cnt,epsilon,True)
  #make convex hull around hand
 hull = cv2.convexHull(cnt)
  #define area of hull and area of hand
 areahull = cv2.contourArea(hull)
 areacnt = cv2.contourArea(cnt)
  #find the percentage of area not covered by hand in convex hull
 arearatio=((areahull-areacnt)/areacnt)*100
  #find the defects in convex hull with respect to hand
 hull = cv2.convexHull(approx, returnPoints=False)
 defects = cv2.convexityDefects(approx, hull)
  # l = no. of defects
 l=0
  cnts2 = cv2.findContours(mask2.copy(), cv2.RETR_EXTERNAL,cv2.CHAIN_APPROX_SIMPLE)
 cnts2 = imutils.grab_contours(cnts2)
 center = None
  c = max(cnts2, key=cv2.contourArea)
  ((x, y), radius) = cv2.minEnclosingCircle(c)
 M = cv2.moments(c)
  center = (int(M["m10"] / M["m00"]), int(M["m01"] / M["m00"]))
 cv2.circle(frame, (int(x), int(y)), 10, [255,125,0], -1)
 pts.appendleft(center)
  for i in np.arange(1, len(pts)):
  if pts[i - 1] is None or pts[i] is None:
 continue
  if counter >= 5 and i == 1 and pts[-5] is not None:
 # compute the difference between the x and y
 # coordinates and re-initialize the direction
 # text variables
 dX = pts[-10][0] - pts[i][0]
 dY = pts[-10][1] - pts[i][1]
 print(areacnt)
  #code for finding no. of defects due to fingers
 for i in range(defects.shape[0]):
 s,e,f,d = defects[i,0]
 start = tuple(approx[s][0])
 end = tuple(approx[e][0])
 far = tuple(approx[f][0])
  pt= (100,180)
  # find length of all sides of triangle
 a = math.sqrt((end[0] - start[0])**2 + (end[1] - start[1])**2)
 b = math.sqrt((far[0] - start[0])**2 + (far[1] - start[1])**2)
 c = math.sqrt((end[0] - far[0])**2 + (end[1] - far[1])**2)
 s = (a+b+c)/2
 ar = math.sqrt(s*(s-a)*(s-b)*(s-c))
  #distance between point and convex hull
 d=(2*ar)/a
  # apply cosine rule here
  angle = math.acos((b**2 + c**2 - a**2)/(2*b*c)) * 57
  # ignore angles > 90 and ignore points very close to convex hull(they generally come due to noise)
 if angle <= 90 and d>30:
 l += 1
  cv2.circle(roi, far, 3, [255,0,0], -1)
 #draw lines around hand
 cv2.line(roi,start, end, [0,255,0], 2)
 l+=1
  #print corresponding gestures which are in their ranges
 font = cv2.FONT_HERSHEY_SIMPLEX
  if l==1:
 if areacnt<2000:
  cv2.putText(frame,'Put hand in the box',(0,50), font, 2, (0,0,255), 3, cv2.LINE_AA)
 else:
  if arearatio<12:
  cv2.putText(frame,'0',(0,50), font, 2, (0,0,255), 3, cv2.LINE_AA)
 elif arearatio<17.5:
  cv2.putText(frame,'Best of luck',(0,50), font, 2, (0,0,255), 3, cv2.LINE_AA)
 else:
  cv2.putText(frame,'1',(0,50), font, 2, (0,0,255), 3, cv2.LINE_AA)
 elif l==2:
  cv2.putText(frame,'2',(0,50), font, 2, (0,0,255), 3, cv2.LINE_AA)
 elif l==3:
 if arearatio<27:
  cv2.putText(frame,'3',(0,50), font, 2, (0,0,255), 3, cv2.LINE_AA)
 else:
  cv2.putText(frame,'ok',(0,50), font, 2, (0,0,255), 3, cv2.LINE_AA)
 elif l==4:
  cv2.putText(frame,'4',(0,50), font, 2, (0,0,255), 3, cv2.LINE_AA)
 elif l==5:
  cv2.putText(frame,'5',(0,50), font, 2, (0,0,255), 3, cv2.LINE_AA)
 elif l==6:
  cv2.putText(frame,'reposition',(0,50), font, 2, (0,0,255), 3, cv2.LINE_AA)
 else :
  cv2.putText(frame,'reposition',(10,50), font, 2, (0,0,255), 3, cv2.LINE_AA)
 #show the windows
 cv2.imshow('mask',mask)
 cv2.imshow('frame',frame)
 cv2.imshow('frame2',frame)
 except:
 pass
 counter += 1
 k = cv2.waitKey(5) & 0xFF
 if k == 27:
 break
cv2.destroyAllWindows()
cap.release()

cv2.destroyAllWindows() cap.release()