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comparison python/cvutils.py @ 801:c5f98916297e

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merged with dev branch
author Nicolas Saunier <nicolas.saunier@polymtl.ca>
date Tue, 31 May 2016 17:07:23 -0400
parents 0662c87a61c9
children 52aa03260f03
comparison
equal deleted inserted replaced
795:a34ec862371f 801:c5f98916297e
216 prop = int2FOURCC(int(prop)) 216 prop = int2FOURCC(int(prop))
217 print('Video {}: {}'.format(cvPropertyNames[cvprop], prop)) 217 print('Video {}: {}'.format(cvPropertyNames[cvprop], prop))
218 else: 218 else:
219 print('Video capture for {} failed'.format(filename)) 219 print('Video capture for {} failed'.format(filename))
220 220
221 def getImagesFromVideo(videoFilename, firstFrameNum = 0, nFrames = 1, saveImage = False, outputPrefix = 'image'): 221 def getImagesFromVideo(videoFilename, firstFrameNum = 0, lastFrameNum = 1, step = 1, saveImage = False, outputPrefix = 'image'):
222 '''Returns nFrames images from the video sequence''' 222 '''Returns nFrames images from the video sequence'''
223 images = [] 223 images = []
224 capture = cv2.VideoCapture(videoFilename) 224 capture = cv2.VideoCapture(videoFilename)
225 if capture.isOpened(): 225 if capture.isOpened():
226 rawCount = capture.get(cv2.CAP_PROP_FRAME_COUNT) 226 rawCount = capture.get(cv2.CAP_PROP_FRAME_COUNT)
227 if rawCount < 0: 227 if rawCount < 0:
228 rawCount = firstFrameNum+nFrames+1 228 rawCount = lastFrameNum+1
229 nDigits = int(floor(log10(rawCount)))+1 229 nDigits = int(floor(log10(rawCount)))+1
230 ret = False 230 ret = False
231 capture.set(cv2.CAP_PROP_POS_FRAMES, firstFrameNum) 231 capture.set(cv2.CAP_PROP_POS_FRAMES, firstFrameNum)
232 imgNum = 0 232 frameNum = firstFrameNum
233 while imgNum<nFrames: 233 while frameNum<=lastFrameNum and frameNum<rawCount:
234 ret, img = capture.read() 234 ret, img = capture.read()
235 i = 0 235 i = 0
236 while not ret and i<10: 236 while not ret and i<10:
237 ret, img = capture.read() 237 ret, img = capture.read()
238 i += 1 238 i += 1
239 if img.size>0: 239 if img is not None and img.size>0:
240 if saveImage: 240 if saveImage:
241 imgNumStr = format(firstFrameNum+imgNum, '0{}d'.format(nDigits)) 241 frameNumStr = format(frameNum, '0{}d'.format(nDigits))
242 cv2.imwrite(outputPrefix+imgNumStr+'.png', img) 242 cv2.imwrite(outputPrefix+frameNumStr+'.png', img)
243 else: 243 else:
244 images.append(img) 244 images.append(img)
245 imgNum +=1 245 frameNum +=step
246 if step > 1:
247 capture.set(cv2.CAP_PROP_POS_FRAMES, frameNum)
246 capture.release() 248 capture.release()
247 else: 249 else:
248 print('Video capture for {} failed'.format(videoFilename)) 250 print('Video capture for {} failed'.format(videoFilename))
249 return images 251 return images
250 252