San Francisco security cameras' choppy video

These consecutive images from a surveillance camera at 16th and Mission streets in San Francisco, taken in the early morning of Aug. 6, 2007, show how slowly the camera took pictures of the scene. Photos courtesy of the San Francisco Police Department less These consecutive images from a surveillance camera at 16th and Mission streets in San Francisco, taken in the early morning of Aug. 6, 2007, show how slowly the camera took pictures of the scene. Photos ... more Image 1 of / 1 Caption Close San Francisco security cameras' choppy video 1 / 1 Back to Gallery

The 68 city-funded cameras perched above San Francisco's toughest street corners have been under fire in recent months for failing to provide evidence leading to arrests, and one of the reasons may be simple:

Choppy video.

Run on a modest budget, Mayor Gavin Newsom's surveillance camera program has produced footage that is disjointed and less clear than the nearly seamless and sharp quality of video that the devices are capable of delivering, a Chronicle review found.

The difference can be dramatic, leaving police with less potential evidence. A review of videos taken last year by four cameras at 16th and Mission streets found a striking problem with the cameras' frame rate, or the number of images produced per second.

Prosecutors and defense attorneys viewed the Mission District footage, taken between 3 a.m. and 4 a.m. Aug. 6, in connection with a robbery case. What they saw looked less like a streaming video than a series of still pictures taken several seconds apart.

In Chicago, where Newsom sampled anti-crime cameras before starting his program, police get motion-picture-quality footage shot at 30 frames per second. But in the San Francisco footage, as many as 10 seconds pass between frames. Some cars and bicycles going through the intersection show up on just a single frame.

"If this is a representation of the system, we're throwing money away," said Theresa Sparks, president of the San Francisco Police Commission, after being shown the footage. The commission regulates use of the cameras.

The problem is only the latest for the 2 1/2-year-old surveillance program, which has contributed to just one arrest in a city where the homicide total in 2007 hit a 12-year high. That lone arrest was more than 19 months ago.

San Francisco officials are also hampering the crime-fighting potential of their program by precluding police from watching video in real time, a nod to privacy concerns. Police are not allowed to maneuver the cameras for a better shot.

In addition, a promised study of the cameras' efficacy has repeatedly been delayed. Under an ordinance that the Board of Supervisors approved in June 2006, police were supposed to have provided data on the cameras' performance to the board and the Police Commission by Jan. 17.

City Administrator Ed Lee was given responsibility for a broader report that would include the data. He has been negotiating for nine months with a team of University of California researchers who want to study the cameras, but officials have not worked out a deal. Lee did not respond to several interview requests. Newsom's office said the report will be ready in early March, though it's unclear who will write it.

"No study has started yet," said Travis Richardson, the development manager for the UC group, the Center for Information Technology Research in the Interest of Society.

Newsom spokesman Nathan Ballard said the mayor planned to review the report on the cameras, which is expected to deal with the quality of the images, among many other aspects of the program.

"If there are problems that can be remedied with further investment, we're open to that possibility," Ballard said.

Newsom said in September, in an opinion piece published in the San Francisco Examiner, that the city had spent $500,000 on the cameras since 2005. But his office gave a much higher cost estimate earlier this month. The true cost of the cameras has amounted to $900,000, Newsom aides said, and the city has budgeted an additional $200,000 for 25 more cameras that the mayor intends to ask the Police Commission to approve.

After being shown the footage from the Mission District intersection, Ballard said, " 'Citizen Kane' it's not," a reference to the revered 1941 film by Orson Welles. But Ballard also said, "We believe these cameras have a deterrent effect on crime. The neighbors appreciate them."

Officials with the city's Department of Telecommunications and Information Services, which operates the cameras, said the ones in the Mission intersection are not representative of the program as a whole. They said that the Mission cameras were hamstrung for more than six months by a poor wireless connection, and that the connection was only recently upgraded.

But they acknowledged that most of the city's cameras achieve only 80 percent of the resolution they are capable of, and that they generate, at best, two to four frames per second because the city lacks the data storage space to accommodate more footage.

Motion pictures and television programs are shown with a frame rate of at least 24 frames per second. Las Vegas casinos are required by regulators to film many gaming areas at 30 frames per second.

That is also the rate generated by more than 550 cameras installed and maintained by the city of Chicago, which has spent millions on the nation's most robust government surveillance of streets and other public places.

Anti-crime cameras in the Contra Costa County city of Pittsburg are typically set at eight to 10 frames per second, officials there said. A BART spokeswoman said her agency's cameras capture from two to 15 frames per second.

The cameras in the Mission, made by IQinVision of San Clemente (Orange County), provide optimal footage at 12 frames per second, said Peter DeAngelis, the company's president.

Officials with San Francisco's telecommunications office said they were doing their best with limited funds. They said they needed hundreds of thousands of dollars' worth of additional data storage space for the footage, which is kept for a week before being erased. The officials also said they were nearly $200,000 short on cash needed for camera maintenance and would have to tap into their own budget to cover the costs.

"Given the resources we have, I think we've done a remarkable job putting in a system that's useful," said the agency's chief operations officer, Richard Robinson.

Even at their best, surveillance cameras have delivered mixed results in studies of their effectiveness at decreasing violent crime.

Under city law, surveillance footage is stored by the city's Department of Emergency Management and may be turned over only to police. The Chronicle obtained the footage from the Mission intersection from the public defender's office, which got it from police while seeking to establish an alibi for two suspects in a robbery case.

The Mission cameras failed to produce even a single frame per second, on average, based on a review of four hours of footage. And there was little consistency to the cameras' frame rate. There were gaps of less than a second and gaps of several seconds.

Over an hour, the most active camera at the intersection delivered one frame every 1.7 seconds, while the least active delivered one frame every 2.9 seconds.

The footage does not show the actual robbery, which occurred two blocks away. Prosecutors dropped charges against the two suspects but said the decision had nothing to do with the footage.

Sparks and Supervisor Ross Mirkarimi, who chairs the board's Public Safety Committee and drafted the ordinance regulating the cameras, both viewed the footage and said the resolution appeared to be sharp enough to make the cameras effective.

But of the frame rate, Mirkarimi said, "If you're going to go through the trouble of installing cameras, at least have the best technology to work with, or let's reroute our dollars."

Newsom, inspired by Chicago's efforts, began his surveillance program in mid-2005 in an attempt to cool violent crime in neighborhoods, including the Western Addition and Bayview-Hunters Point. City records show that police asked to see footage last year about once a week. Chicago and Pittsburg police watch footage almost constantly.

Ballard said Newsom's request for 25 additional cameras would not go to the Police Commission until the report on the cameras' performance is completed. But the mayor faces an increasingly skeptical commission, whose members have the authority to approve - or remove - cameras.

Watch a video clip from a San Francisco surveillance camera online at sfgate.com.