Media stocks have been tanking on analyst concerns that ad dollars are shifting to the Internet. But the move to online advertising brings another problem: The growth of ad blocking.

Ad blockers are expected to cost the industry $22 billion in revenue this year, according to a report by Adobe and PageFair, a company that helps publishers work around and measure ad blockers. The research projects that the number of people regularly blocking ads will grow 41 percent to 200 million by the end of 2015.