tmnxVdoGrpSrcVqmAvgGOPLength 1.3.6.1.4.1.6527.3.1.2.61.1.18.1.26

The value of tmnxVdoGrpSrcVqmAvgGOPLength indicates the average distance in a Group Of Pictures (GOP) between two consecutive I-frames within a sequence of frames in that video stream on a multicast channel.