sentences:  This group, with a membership of over 300 experts, representing 20 countries and various industries having a stake in digital audio and video, produced the MPEG-1 and MPEG-2 standards that have facilitated the digital audio-visual revolution.In 1999, he was asked to be the Executive Director of Secure Digital Music Initiative, a forum comprising hundreds of companies to develop specifications for an open standard secure digital music delivery technology.He stepped down from this post in 2001, having expressed frustration about conflicts between the members of the group, which had failed to produce effective anti-piracy specifications.