Police across the country are using increasingly sophisticated surveillance systems to monitor daily life in their communities. Ultra-high-definition cameras, software that can read license plates and recognize faces, and systems that can alert police to suspicious behavior have given law enforcement unprecedented access to our everyday activities.

Average citizens and privacy advocates say the ability to monitor and record public activity at such an extraordinary level is a threat to personal privacy.

They want more stringent guidelines on how this technology can be used and what happens to the thousands of hours of daily life captured in police computers when the footage is not used to prosecute a crime.

Few regulations govern the use of these powerful surveillance techniques, and new technology is often rolled out with little fanfare.

“Technology is advancing at a pace that far outstrips legislation, regulation and policy formulation,” said Jim Bueermann, president of the nonprofit Police Foundation, which works to improve policing in America.

The latest surveillance technology includes:

• High-speed cameras capable of capturing photos of passing license plates, paired with software that compares plate numbers with lists of wanted suspects, missing persons or stolen vehicles.
• Networks of high-definition cameras that can be coupled with software that recognizes faces or sends alerts on suspicious activities.
• Aerial drones with high-definition and night-vision cameras.
• Wide-area aerial surveillance capable of recording every movement across the scope of a small city for hours.

And these technologies are not just for big cities.

Sophisticated surveillance systems used to be limited to major world cities.

But falling prices for equipment and access to hundreds of millions of federal anti-terrorism dollars have enabled large, mid-sized and even some small American cities to increase their surveillance capabilities.

The cost of surveillance equipment is forecast to decline about 10 percent this year, making purchases even more viable for police departments.