The days when a viewer sees a TV commercial that seems irrelevant may be coming to an end, as advertising tailored to a person or audience grows in popularity with marketers.

In the U.S., advertisers are expected to spend $1.26 billion on this type of targeted commercial in 2017, with that figure increasing to $3.04 billion in 2019, according to estimates by researcher eMarketer.

So-called "addressable" TV advertising has been growing slowly over the past couple of years but is projected to make up 4 percent of TV spend in 2019, up from 0.6 percent in 2015.

It is gaining in popularity because of the ability to understand the return on investment for TV ad spend, something that has traditionally been hard to measure.

"This additional addressable advertising layer means that ads reach in-target households more frequently, thereby reducing wasted ad impressions and improving the overall advertising impact," eMarketer's report stated.