+            'id': 'XNjA1NzA2Njgw',
+            'title': '邢義田复旦讲座之想象中的胡人—从“左衽孔子”说起',
+        },
+        'playlist_count': 19,
+        'params': {
+            'videopassword': '100600',
+        },
+    }]
+
+    def construct_video_urls(self, data):
+        # get sid, token
+        def yk_t(s1, s2):
+            ls = list(range(256))
+            t = 0
+            for i in range(256):
+                t = (t + ls[i] + compat_ord(s1[i % len(s1)])) % 256
+                ls[i], ls[t] = ls[t], ls[i]
+            s = bytearray()
+            x, y = 0, 0
+            for i in range(len(s2)):
+                y = (y + 1) % 256
+                x = (x + ls[y]) % 256
+                ls[x], ls[y] = ls[y], ls[x]
+                s.append(compat_ord(s2[i]) ^ ls[(ls[x] + ls[y]) % 256])
+            return bytes(s)
+
+        sid, token = yk_t(
+            b'becaf9be', base64.b64decode(data['security']['encrypt_string'].encode('ascii'))
+        ).decode('ascii').split('_')
+
+        # get oip
+        oip = data['security']['ip']
+
+        fileid_dict = {}
+        for stream in data['stream']:
+            format = stream.get('stream_type')
+            fileid = stream['stream_fileid']
+            fileid_dict[format] = fileid
+
+        def get_fileid(format, n):
+            number = hex(int(str(n), 10))[2:].upper()
+            if len(number) == 1:
+                number = '0' + number
+            streamfileids = fileid_dict[format]
+            fileid = streamfileids[0:8] + number + streamfileids[10:]
+            return fileid
+
+        # get ep
+        def generate_ep(format, n):
+            fileid = get_fileid(format, n)
+            ep_t = yk_t(
+                b'bf7e5f01',
+                ('%s_%s_%s' % (sid, fileid, token)).encode('ascii')
+            )
+            ep = base64.b64encode(ep_t).decode('ascii')
+            return ep
+
+        # generate video_urls
+        video_urls_dict = {}
+        for stream in data['stream']:
+            format = stream.get('stream_type')
+            video_urls = []
+            for dt in stream['segs']:
+                n = str(stream['segs'].index(dt))
+                param = {
+                    'K': dt['key'],
+                    'hd': self.get_hd(format),
+                    'myp': 0,
+                    'ypp': 0,
+                    'ctype': 12,
+                    'ev': 1,
+                    'token': token,
+                    'oip': oip,
+                    'ep': generate_ep(format, n)
+                }
+                video_url = \
+                    'http://k.youku.com/player/getFlvPath/' + \
+                    'sid/' + sid + \
+                    '_00' + \
+                    '/st/' + self.parse_ext_l(format) + \
+                    '/fileid/' + get_fileid(format, n) + '?' + \
+                    compat_urllib_parse.urlencode(param)
+                video_urls.append(video_url)
+            video_urls_dict[format] = video_urls
+
+        return video_urls_dict
+
+    @staticmethod
+    def get_ysuid():
+        return '%d%s' % (int(time.time()), ''.join([
+            random.choice(string.ascii_letters) for i in range(3)]))
+
+    def get_hd(self, fm):
+        hd_id_dict = {
+            '3gp': '0',
+            '3gphd': '1',
+            'flv': '0',
+            'flvhd': '0',
+            'mp4': '1',
+            'mp4hd': '1',
+            'mp4hd2': '1',
+            'mp4hd3': '1',
+            'hd2': '2',
+            'hd3': '3',