| commit | author | age | ||
| e555c0 | 1 | from pyzbar.pyzbar import decode |
| 0d97e9 | 2 | from .sid_process import getSID |
| e555c0 | 3 | import cv2 |
| SP | 4 | import numpy as np |
| 0d97e9 | 5 | |
| SP | 6 | import pkg_resources |
| 7 | ||
| 8 | markerfile = '/template.png' # always use slash | |
| 9 | markerfilename = pkg_resources.resource_filename(__name__, markerfile) | |
| 10 | ||
| e555c0 | 11 | |
| SP | 12 | |
| 511c2e | 13 | class Paper: |
| 762a5e | 14 | def __init__(self, filename=None, sid_classifier=None, settings=None): |
| 511c2e | 15 | self.filename = filename |
| SP | 16 | self.invalid = None |
| 17 | self.QRData = None | |
| e0996e | 18 | self.settings = {"answer_threshold": 0.25} if settings is None else settings |
| 511c2e | 19 | self.errors = [] |
| SP | 20 | self.warnings = [] |
| e0996e | 21 | self.sid = None |
| 762a5e | 22 | self.sid_classifier = sid_classifier |
| 511c2e | 23 | if filename is not None: |
| SP | 24 | self.loadImage(filename) |
| 25 | self.runOcr() | |
| e555c0 | 26 | |
| 511c2e | 27 | def loadImage(self, filename, rgbchannel=0): |
| SP | 28 | self.img = cv2.imread(filename, rgbchannel) |
| 29 | if self.img is None: | |
| 30 | self.errors.append("File could not be loaded!") | |
| 31 | self.invalid = True | |
| 32 | return | |
| 33 | self.imgHeight, self.imgWidth = self.img.shape[0:2] | |
| e555c0 | 34 | |
| 0d97e9 | 35 | def saveImage(self, filename="/tmp/debug_image.png"): |
| 511c2e | 36 | cv2.imwrite(filename, self.img) |
| e555c0 | 37 | |
| 511c2e | 38 | def runOcr(self): |
| SP | 39 | if self.invalid == True: |
| 40 | return | |
| 41 | self.decodeQRandRotate() | |
| 42 | self.imgTreshold() | |
| 43 | skewAngle = 0 | |
| 44 | # try: | |
| 45 | # skewAngle=self.getSkewAngle() | |
| 46 | # except: | |
| 47 | # self.errors.append("Could not determine skew angle!") | |
| 48 | # self.rotateAngle(skewAngle) | |
| e555c0 | 49 | |
| 511c2e | 50 | self.generateAnswerMatrix() |
| e555c0 | 51 | |
| 511c2e | 52 | self.saveImage() |
| e555c0 | 53 | |
| 511c2e | 54 | def decodeQRandRotate(self): |
| SP | 55 | if self.invalid == True: |
| 56 | return | |
| 57 | blur = cv2.blur(self.img, (3, 3)) | |
| 58 | d = decode(blur) | |
| 59 | self.img = blur | |
| 60 | if len(d) == 0: | |
| 61 | self.errors.append("QR code could not be found!") | |
| 62 | self.data = None | |
| 63 | self.invalid = True | |
| 64 | return | |
| e0996e | 65 | if(len(d)>1): #if there are multiple codes, get first ean or qr code available. |
| SP | 66 | for dd in d: |
| 67 | if(dd.type=="EAN13" or dd.type=="QR"): | |
| 68 | d[0]=dd | |
| 69 | break | |
| 511c2e | 70 | self.QRDecode = d |
| SP | 71 | self.QRData = d[0].data |
| 72 | xpos = d[0].rect.left | |
| 73 | ypos = d[0].rect.top | |
| 74 | # check if image is rotated wrongly | |
| 82ec6d | 75 | if xpos > self.imgHeight / 2.0 and ypos > self.imgWidth / 2.0: |
| 511c2e | 76 | self.rotateAngle(180) |
| e555c0 | 77 | |
| 511c2e | 78 | def rotateAngle(self, angle=0): |
| e0996e | 79 | # rot_mat = cv2.getRotationMatrix2D( |
| 82ec6d | 80 | # (self.imgHeight / 2, self.imgWidth / 2), angle, 1.0 |
| e0996e | 81 | # ) |
| 511c2e | 82 | rot_mat = cv2.getRotationMatrix2D( |
| e0996e | 83 | (self.imgWidth / 2, self.imgHeight / 2), angle, 1.0 |
| 511c2e | 84 | ) |
| SP | 85 | result = cv2.warpAffine( |
| 86 | self.img, | |
| 87 | rot_mat, | |
| 82ec6d | 88 | (self.imgWidth, self.imgHeight), |
| 511c2e | 89 | flags=cv2.INTER_CUBIC, |
| SP | 90 | borderMode=cv2.BORDER_CONSTANT, |
| 91 | borderValue=(255, 255, 255), | |
| 92 | ) | |
| e555c0 | 93 | |
| 511c2e | 94 | self.img = result |
| SP | 95 | self.imgHeight, self.imgWidth = self.img.shape[0:2] |
| e555c0 | 96 | |
| 511c2e | 97 | # todo, make better tresholding |
| e555c0 | 98 | |
| 511c2e | 99 | def imgTreshold(self): |
| SP | 100 | (self.thresh, self.bwimg) = cv2.threshold( |
| 101 | self.img, 128, 255, cv2.THRESH_BINARY | cv2.THRESH_OTSU | |
| 102 | ) | |
| e555c0 | 103 | |
| 511c2e | 104 | def getSkewAngle(self): |
| SP | 105 | neg = 255 - self.bwimg # get negative image |
| 0d97e9 | 106 | cv2.imwrite("/tmp/debug_1.png", neg) |
| e555c0 | 107 | |
| 511c2e | 108 | angle_counter = 0 # number of angles |
| SP | 109 | angle = 0.0 # collects sum of angles |
| 110 | cimg = cv2.cvtColor(self.img, cv2.COLOR_GRAY2BGR) | |
| e555c0 | 111 | |
| 511c2e | 112 | # get all the Hough lines |
| SP | 113 | for line in cv2.HoughLinesP(neg, 1, np.pi / 180, 325): |
| 114 | x1, y1, x2, y2 = line[0] | |
| 115 | cv2.line(cimg, (x1, y1), (x2, y2), (0, 0, 255), 2) | |
| 116 | # calculate the angle (in radians) | |
| 117 | this_angle = np.arctan2(y2 - y1, x2 - x1) | |
| 118 | if this_angle and abs(this_angle) <= 10: | |
| 119 | # filtered zero degree and outliers | |
| 120 | angle += this_angle | |
| 121 | angle_counter += 1 | |
| e555c0 | 122 | |
| 511c2e | 123 | # the skew is calculated of the mean of the total angles, #try block helps with division by zero. |
| SP | 124 | try: |
| 125 | skew = np.rad2deg( | |
| 126 | angle / angle_counter | |
| 127 | ) # the 1.2 factor is just experimental.... | |
| 128 | except: | |
| 129 | skew = 0 | |
| e555c0 | 130 | |
| 0d97e9 | 131 | cv2.imwrite("/tmp/debug_2.png", cimg) |
| 511c2e | 132 | return skew |
| e555c0 | 133 | |
| 511c2e | 134 | def locateUpMarkers(self, threshold=0.85, height=200): |
| 0d97e9 | 135 | template = cv2.imread(markerfilename, 0) |
| 511c2e | 136 | w, h = template.shape[::-1] |
| SP | 137 | crop_img = self.img[0:height, :] |
| 138 | res = cv2.matchTemplate(crop_img, template, cv2.TM_CCOEFF_NORMED) | |
| 139 | loc = np.where(res >= threshold) | |
| 140 | cimg = cv2.cvtColor(crop_img, cv2.COLOR_GRAY2BGR) | |
| 141 | # remove false matching of the squares in qr code | |
| 142 | loc_filtered_x = [] | |
| 143 | loc_filtered_y = [] | |
| 144 | if len(loc[0]) == 0: | |
| 145 | min_y = -1 | |
| 146 | else: | |
| 147 | min_y = np.min(loc[0]) | |
| 148 | for pt in zip(*loc[::-1]): | |
| 149 | if pt[1] < min_y + 20: | |
| 150 | loc_filtered_y.append(pt[1]) | |
| 151 | loc_filtered_x.append(pt[0]) | |
| 152 | # order by x coordinate | |
| 153 | loc_filtered_x, loc_filtered_y = zip( | |
| 154 | *sorted(zip(loc_filtered_x, loc_filtered_y)) | |
| 155 | ) | |
| 02e0f7 | 156 | # loc=[loc_filtered_y,loc_filtered_x] |
| SP | 157 | # remove duplicates |
| 511c2e | 158 | a = np.diff(loc_filtered_x) > 40 |
| SP | 159 | a = np.append(a, True) |
| 160 | loc_filtered_x = np.array(loc_filtered_x) | |
| 161 | loc_filtered_y = np.array(loc_filtered_y) | |
| 162 | loc = [loc_filtered_y[a], loc_filtered_x[a]] | |
| 163 | for pt in zip(*loc[::-1]): | |
| 164 | cv2.rectangle(cimg, pt, (pt[0] + w, pt[1] + h), (0, 255, 255), 2) | |
| e555c0 | 165 | |
| 0d97e9 | 166 | cv2.imwrite("/tmp/debug_3.png", cimg) |
| e555c0 | 167 | |
| 511c2e | 168 | self.xMarkerLocations = loc |
| SP | 169 | return loc |
| e555c0 | 170 | |
| 511c2e | 171 | def locateRightMarkers(self, threshold=0.85, width=200): |
| 0d97e9 | 172 | template = cv2.imread(markerfilename, 0) |
| 511c2e | 173 | w, h = template.shape[::-1] |
| SP | 174 | crop_img = self.img[:, -width:] |
| 175 | res = cv2.matchTemplate(crop_img, template, cv2.TM_CCOEFF_NORMED) | |
| 176 | loc = np.where(res >= threshold) | |
| 177 | cimg = cv2.cvtColor(crop_img, cv2.COLOR_GRAY2BGR) | |
| 178 | # remove false matching of the squares in qr code | |
| 179 | loc_filtered_x = [] | |
| 180 | loc_filtered_y = [] | |
| 181 | if len(loc[1]) == 0: | |
| 182 | min_x = -1 | |
| 183 | else: | |
| 184 | max_x = np.max(loc[1]) | |
| 185 | for pt in zip(*loc[::-1]): | |
| 186 | if pt[1] > max_x - 20: | |
| 187 | loc_filtered_y.append(pt[1]) | |
| 188 | loc_filtered_x.append(pt[0]) | |
| 189 | # order by y coordinate | |
| 190 | loc_filtered_y, loc_filtered_x = zip( | |
| 191 | *sorted(zip(loc_filtered_y, loc_filtered_x)) | |
| 192 | ) | |
| 193 | # loc=[loc_filtered_y,loc_filtered_x] | |
| 194 | # remove duplicates | |
| 195 | a = np.diff(loc_filtered_y) > 40 | |
| 196 | a = np.append(a, True) | |
| 197 | loc_filtered_x = np.array(loc_filtered_x) | |
| 198 | loc_filtered_y = np.array(loc_filtered_y) | |
| 199 | loc = [loc_filtered_y[a], loc_filtered_x[a]] | |
| 200 | for pt in zip(*loc[::-1]): | |
| 201 | cv2.rectangle(cimg, pt, (pt[0] + w, pt[1] + h), (0, 255, 255), 2) | |
| e555c0 | 202 | |
| 0d97e9 | 203 | cv2.imwrite("/tmp/debug_4.png", cimg) |
| e555c0 | 204 | |
| 511c2e | 205 | self.yMarkerLocations = [loc[0], loc[1] + self.imgWidth - width] |
| SP | 206 | return self.yMarkerLocations |
| e555c0 | 207 | |
| 511c2e | 208 | def generateAnswerMatrix(self): |
| SP | 209 | self.locateUpMarkers() |
| 210 | self.locateRightMarkers() | |
| e555c0 | 211 | |
| 511c2e | 212 | roixoff = 10 |
| SP | 213 | roiyoff = 5 |
| 214 | roiwidth = 50 | |
| 215 | roiheight = roiwidth | |
| 216 | totpx = roiwidth * roiheight | |
| e555c0 | 217 | |
| 511c2e | 218 | self.answerMatrix = [] |
| SP | 219 | for y in self.yMarkerLocations[0]: |
| 220 | oneline = [] | |
| 221 | for x in self.xMarkerLocations[1]: | |
| 222 | roi = self.bwimg[ | |
| 223 | y - roiyoff : y + int(roiheight - roiyoff), | |
| 224 | x - roixoff : x + int(roiwidth - roixoff), | |
| 225 | ] | |
| 226 | # cv2.imwrite('ans_x'+str(x)+'_y_'+str(y)+'.png',roi) | |
| 227 | black = totpx - cv2.countNonZero(roi) | |
| 228 | oneline.append(black / totpx) | |
| 229 | self.answerMatrix.append(oneline) | |
| 9efc18 | 230 | |
| SP | 231 | def get_enhanced_sid(self): |
| 02e0f7 | 232 | if self.sid_classifier is None: |
| SP | 233 | return "x" |
| 762a5e | 234 | if self.settings is not None: |
| e0996e | 235 | sid_mask = self.settings.get("sid_mask", None) |
| SP | 236 | es, err, warn = getSID( |
| 02e0f7 | 237 | self.img[ |
| d5c694 | 238 | int(0.04 * self.imgHeight) : int(0.095 * self.imgHeight), |
| 02e0f7 | 239 | int(0.7 * self.imgWidth) : int(0.99 * self.imgWidth), |
| SP | 240 | ], |
| 241 | self.sid_classifier, | |
| e0996e | 242 | sid_mask, |
| 02e0f7 | 243 | ) |
| 5cb7c1 | 244 | [self.errors.append(e) for e in err] |
| SP | 245 | [self.warnings.append(w) for w in warn] |
| 02e0f7 | 246 | return es |
| 0436f6 | 247 | |
| SP | 248 | def get_code_data(self): |
| cf921b | 249 | if self.QRData is None: |
| SP | 250 | self.errors.append("Could not read QR or EAN code! Not an exam?") |
| e0996e | 251 | retval = { |
| SP | 252 | "exam_id": None, |
| 253 | "page_no": None, | |
| 254 | "paper_id": None, | |
| 255 | "faculty_id": None, | |
| 256 | "sid": None, | |
| 0436f6 | 257 | } |
| e0996e | 258 | return retval |
| SP | 259 | qrdata = bytes.decode(self.QRData, "utf8") |
| 260 | if self.QRDecode[0].type == "EAN13": | |
| 261 | return { | |
| 262 | "exam_id": int(qrdata[0:7]), | |
| 263 | "page_no": int(qrdata[7]), | |
| 264 | "paper_id": int(qrdata[-5:-1]), | |
| 265 | "faculty_id": None, | |
| 266 | "sid": None, | |
| 267 | } | |
| 268 | else: | |
| 269 | data = qrdata.split(",") | |
| 270 | retval = { | |
| 271 | "exam_id": int(data[1]), | |
| 272 | "page_no": int(data[3]), | |
| 273 | "paper_id": int(data[2]), | |
| 274 | "faculty_id": int(data[0]), | |
| 275 | } | |
| 276 | if len(data) > 4: | |
| 277 | retval["sid"] = data[4] | |
| 0436f6 | 278 | |
| SP | 279 | return retval |
| 280 | ||
| 281 | def get_paper_ocr_data(self): | |
| e0996e | 282 | data = self.get_code_data() |
| SP | 283 | data["qr"] = self.QRData |
| 284 | data["errors"] = self.errors | |
| 285 | data["warnings"] = self.warnings | |
| 286 | data["up_position"] = ( | |
| 287 | list(self.xMarkerLocations[1] / self.imgWidth), | |
| 288 | list(self.yMarkerLocations[1] / self.imgHeight), | |
| 289 | ) | |
| 290 | data["right_position"] = ( | |
| 291 | list(self.xMarkerLocations[1] / self.imgWidth), | |
| 292 | list(self.yMarkerLocations[1] / self.imgHeight), | |
| 293 | ) | |
| 294 | data["ans_matrix"] = ( | |
| 295 | (np.array(self.answerMatrix) > self.settings["answer_threshold"]) * 1 | |
| 296 | ).tolist() | |
| 297 | if data["sid"] is None and data["page_no"] == 0: | |
| 298 | data["sid"] = self.get_enhanced_sid() | |
| 0436f6 | 299 | return data |
