The paper deals with an objective assessment of IP video calls transmission over GSM and UMTS networks. Video transmission is affected by many factors in mobile network. Among these factors belong packet loss, latency and transmission rate of the mobile network. Network properties were simulated by Simena network simulator. Our team have developed a unique technique for finding defects in video appearing in video calls. This technique is built on modified Asterisk SW PBX with enabled video recording and playback functions. Transmitted video files are compared with original video file by means of size of transmitted video file and in-video-defects. We are using MSU VQMT software for finding in video defects; more precisely we are using VQM method for comparing two video sources.