I am primaily involved in the following organizations (I also follow the work in DVB, W3C, 3GPP (SA4), HbbTV, ATSC and SCTE):

Individual contributor and working group (PAYLOAD) co-chair (since 2007). My list of 20+ RFCs, author stats page, list of active drafts and list of expired drafts .

Individual contributor, editor and subgroup (DASH) co-chair (since 2010). I have also been the head of delegation for the Turkish National Body for JPEG and MPEG since late 2017.
Individual contributor and editor (since 2012).
Individual contributor, editor and study group (Players and Playback) co-chair (since 2016).
Individual contributor and editor (since 2018).