In video conferencing, if two people talk at the same time howling noises can appear due to failures in the echo cancellation system. In order to reduce these noise situations, a novel AEC (Acoustic Echo Cancellation) system is proposed by using audio and video information. Through image processing techniques we have developed a new DTD (Double Talk Detector) based on video information (video-DTD). A novel Acoustic Echo Cancellation system was successfully developed, integrating audio and video information. In simulated results using data from a real scenary the misalignment of the new AEC (with video-DTD) was smaller than a traditional AEC. © 2012 IEEE.