• by Laurie Sullivan  @lauriesullivan, April 11, 2016

Share of original broadcast videos continue to fall on Facebook, and with them insights into the likes and dislikes of what makes site members tick. This year video shares on Facebook are down 15% compared with last, according to one report.

As Facebook executives prepare for Tuesday's F8 conference, the social site continues to encourage more postings of person videos on the site. Last week it launched a visual search engine to get users to watch more original content.

While the company tries to reverse that trend, execs at the F8 conference will begin highlighting the ability to move the smartphone live video revolution to TV-like production content.

Facebook wants a bigger slice of video views. eMarketer estimates that in the U.S. about 213.2 million people will watch digital video, rising to 224.5 million by 2018. The research firm puts U.S. digital video ad spend at about $9.84 billion in 2016, up 28.5% compared with last year, and $13.39 billion by 2018. On mobile video ad spend will reach $4.24 billion in the U.S. in 2016, while desktop will reach $5.60 billion.

A dedicated search engine to search for video streams could help Facebook gain the traction it needs to make Live more useful. The feature will allow Facebook members to search features for the videos that other members share instantly by typing a few keywords into the search bar at the top of the screen.

Insiders expect the company to highlight live video and features in messenger.

"Facebook is on a path to create distance between brands and their customers, and eventually to dominate customers' mobile moments and better serve them," Forrester Research VP and principal analyst Julie Ask writes in a post. "And they will, because Facebook understands customers better than the brands.”

Forrester estimates that consumers spend more than 80% of their time in just five apps each month, and one or two of those are typically social media or instant messaging platforms owned by Apple, Google, and Facebook.

Chatbots, similar to the feature Facebook is expected to launch at F8, will become a catalyst for growth. eMarketer estimates about 1.61 billion mobile messaging app users in 2016 worldwide, about 22% of the population. This year in the U.S., 128.5 million people will use a mobile messaging app, up 13.9% compared with 2015.