VideoStream.py

__author__ = 'Tibbers'
import struct
class VideoStream:
	def __init__(self, filename):
		self.filename = filename
		try:
			self.file = open(filename, 'rb')
			print '-'*60 +  "\nVideo file : |" + filename +  "| read\n" + '-'*60
		except:
			print "read " + filename + " error"
			raise IOError
		self.frameNum = 0

	def nextFrame(self):
		"""Get next frame."""

		data = self.file.read(5) # Get the framelength from the first 5 bytes
		#data_ints = struct.unpack('<' + 'B'*len(data),data)
		data = bytearray(data)

		data_int = (data[0] - 48) * 10000 + (data[1] - 48) * 1000 + (data[2] - 48) * 100 + (data[3] - 48) * 10 + (data[4] - 48)# = #int(data.encode('hex'),16)

		final_data_int = data_int

		if data:

			framelength = final_data_int#int(data)#final_data_int/8  # xx bytes
			# Read the current frame
			frame = self.file.read(framelength)
			if len(frame) != framelength:
				raise ValueError('incomplete frame data')
			#print "frame length"
			#print len(frame)
			#if not (data.startswith(b'\xff\xd8') and data.endswith(b'\xff\xd9')):
			#	raise ValueError('invalid jpeg')

			self.frameNum += 1
			print '-'*10 + "\nNext Frame (#" + str(self.frameNum) + ") length:" + str(framelength) + "\n" + '-'*10

			return frame

	def frameNbr(self):
		"""Get frame number."""
		return self.frameNum