GO_23.ipynb

{
 "cells": [
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [],
   "source": [
    "import numpy as np\n",
    "import cv2"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [],
   "source": [
    "feature_params = dict(maxCorners = 10,qualityLevel=0.3,minDistance=7,blockSize=7)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [],
   "source": [
    "ak_params=dict(winSize=(200,200),maxLevel=2,criteria=(cv2.TERM_CRITERIA_EPS | cv2.TERM_CRITERIA_COUNT,10,0.03))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "ename": "error",
     "evalue": "OpenCV(4.1.0) C:\\projects\\opencv-python\\opencv\\modules\\imgproc\\src\\color.cpp:182: error: (-215:Assertion failed) !_src.empty() in function 'cv::cvtColor'\n",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31merror\u001b[0m                                     Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-5-6c7efda1b7b6>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[0;32m     12\u001b[0m \u001b[1;31m# Take first frame and find corners in it\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m     13\u001b[0m \u001b[0mret\u001b[0m\u001b[1;33m,\u001b[0m \u001b[0mold_frame\u001b[0m \u001b[1;33m=\u001b[0m \u001b[0mcap\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mread\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m---> 14\u001b[1;33m \u001b[0mold_gray\u001b[0m \u001b[1;33m=\u001b[0m \u001b[0mcv2\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mcvtColor\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mold_frame\u001b[0m\u001b[1;33m,\u001b[0m \u001b[0mcv2\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mCOLOR_BGR2GRAY\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m\u001b[0;32m     15\u001b[0m \u001b[0mp0\u001b[0m \u001b[1;33m=\u001b[0m \u001b[0mcv2\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mgoodFeaturesToTrack\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mold_gray\u001b[0m\u001b[1;33m,\u001b[0m \u001b[0mmask\u001b[0m \u001b[1;33m=\u001b[0m \u001b[1;32mNone\u001b[0m\u001b[1;33m,\u001b[0m \u001b[1;33m**\u001b[0m\u001b[0mfeature_params\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m     16\u001b[0m \u001b[1;33m\u001b[0m\u001b[0m\n",
      "\u001b[1;31merror\u001b[0m: OpenCV(4.1.0) C:\\projects\\opencv-python\\opencv\\modules\\imgproc\\src\\color.cpp:182: error: (-215:Assertion failed) !_src.empty() in function 'cv::cvtColor'\n"
     ]
    }
   ],
   "source": [
    "cap=cv2.VideoCapture(0)\n",
    "\n",
    "# params for ShiTomasi corner detection\n",
    "feature_params = dict(maxCorners = 100,qualityLevel = 0.3,minDistance = 7,blockSize = 7)\n",
    "   \n",
    "# Parameters for lucas kanade optical flow\n",
    "ak_params = dict(winSize  = (15,15),maxLevel = 2,criteria = (cv2.TERM_CRITERIA_EPS | cv2.TERM_CRITERIA_COUNT, 10, 0.03))\n",
    " \n",
    "# Create some random colors\n",
    "color = np.random.randint(0,255,(100,3))\n",
    "\n",
    "# Take first frame and find corners in it\n",
    "ret, old_frame = cap.read()\n",
    "old_gray = cv2.cvtColor(old_frame, cv2.COLOR_BGR2GRAY)\n",
    "p0 = cv2.goodFeaturesToTrack(old_gray, mask = None, **feature_params)\n",
    "\n",
    "# Create a mask image for drawing purposes\n",
    "mask = np.zeros_like(old_frame)\n",
    "\n",
    "while(1):\n",
    "    ret,frame = cap.read()\n",
    "    frame_gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)\n",
    "   \n",
    "    # calculate optical flow\n",
    "    p1, st, err = cv2.calcOpticalFlowPyrLK(old_gray, frame_gray, p0, None, **ak_params)\n",
    " \n",
    "    # Select good points\n",
    "    good_new = p1[st==1]\n",
    "    good_old = p0[st==1]\n",
    "\n",
    "    # draw the tracks\n",
    "    for i,(new,old) in enumerate(zip(good_new,good_old)):\n",
    "        a,b = new.ravel()\n",
    "        c,d = old.ravel()\n",
    "        mask = cv2.line(mask, (a,b),(c,d), color[i].tolist(), 2)\n",
    "        frame = cv2.circle(frame,(a,b),5,color[i].tolist(),-1)\n",
    "    img = cv2.add(frame,mask)\n",
    " \n",
    "    cv2.imshow('frame',img)\n",
    "    k = cv2.waitKey(30) & 0xff\n",
    "    if k == 27:\n",
    "        break\n",
    "    # Now update the previous frame and previous points\n",
    "    old_gray = frame_gray.copy()\n",
    "    p0 = good_new.reshape(-1,1,2)\n",
    " \n",
    "cv2.destroyAllWindows()\n",
    "cap.release()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
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