Local buses, trains and even some train stations have been slathered in advertising in recent years to raise money for cash-strapped transit agencies.
On Tuesday, commercial messages on mass transit in the Southland reached a new frontier when subway riders began seeing a 15-second video floating outside the train's window in a dark tunnel near Universal City.
The first ad was a short promo for the film "Speed Racer," featuring the main character's car zipping and flipping about. An ad for Target began showing later in the morning, complete with dancing models.
"It's intrusive to me," said passenger Roberta Richey, an actress. "If I want to see that, I'll turn on the TV or pick up a newspaper."
Reaction from most other passengers on a northbound Red Line train Tuesday morning was muted or nonexistent. The videos have no sound, and some riders didn't notice them. Others read; some slept or stared blankly ahead in the way that subway riders do.
And others liked what they saw in the tunnel between the Hollywood and Highland and Universal City stations.
"We were, like, freaking out. We were saying 'What are they going to think of next?' " said Ray Mann, a film producer, who first saw the ads last week when they were being tested. "The fact is that it worked. It caught my attention."
Which, proponents say, is precisely the point. Such video ads have become part of the subway landscape in San Francisco and New York and are even more prominent overseas.
But they also have raised hackles among those who see the line increasingly blurring between public space and commercial messages. The selling of naming rights to stadiums and placement of billboards have been widely debated nationally but seem less controversial on mass transit.
When officials decided to put a video ad in a subway tunnel in San Francisco, for example, only one member of the board of the Bay Area Rapid Transit District voted no, saying that it was wrong to sell the attention of passengers.
The firms that sell the video systems and ads say marketing surveys have shown that riders are more likely to remember products featured on subway tunnel ads because the ads are unique.
"With outdoor billboards, you never know how many people are actually seeing it," said Michael Swistun, the chief executive of Sidetrack Technologies, which built the system being used on the Red Line.
With the tunnel videos, he said, "I know that you can't leave the room, and you can't change the channel."
The videos are actually a series of 360 LED lights that are hung over a quarter-mile span of the tunnel. When trains go past the lights at a certain range of speeds, the human eye perceives movement -- although the image is far shakier than one on a television.
Sidetrack's system is different from those in other cities, where the videos are created by lighted panels attached to the tunnels -- meaning that the same ad is played until the panels are changed. The LED display allows Sidetrack, from its Winnipeg, Canada, headquarters, to rotate among as many as 18 different ads; the right to show the ad sells for about $55,000 a month.
Transit agencies such as the MTA like the ads because they provide much-needed revenue. The agency proposed its $3.4-billion budget Tuesday for the next fiscal year, which includes about $23.6 million in ad revenue. But the agency is also bracing to lose funds from Sacramento because of the state budget crisis.
The MTA makes a flat fee of $240,000 from the video ads and also stands to get a cut of any profits reaped over $1 million. Officials also say that the ads are an amenity that will brighten an otherwise dreary subway tunnel.
"We feel like this makes the experience of riding a little nicer," said Warren Morse, the agency's deputy executive officer for communications.
Over the last three years the MTA has become much more aggressive in courting ad revenue, settling on a policy that ads are a "responsible means of maximizing the use of capital investments" as long as they don't compromise safety.
The agency has cloaked both the outside of its trains and some train stations in advertising, and most of its buses have television sets that show both ads and programs. Ads are also now being sold for the inside of rail cars, and the agency even considered selling ad space on the stripes between spaces in its parking lots.
Transit advocates in the region said the need for money often trumps aesthetic ideals.
"Things like this are ongoing sources of revenue," said Kymberleigh Richards, a spokesperson for Southern California Transit Advocates. "If you get more of that money, then you are able to continue service and plan new projects without jeopardizing either."
Dennis Hathaway, a spokesman for the Coalition to Ban Billboard Blight, considers the tunnel ads -- which he hasn't seen -- part of a trend to commercialize public space to help fill public coffers.
"Do we want to sell our public space in order to have public transportation, parks and other amenities?" Hathaway asked. "If the people in the city decide 'yes,' that's OK, and I'll accept that and probably move somewhere else. But there needs to be that debate."