Predictive Focus Algorithm (PFA)

Current Challenges

With a rise in demand for long-distance surveillance solutions, Large optical zoom PTZ cameras are gaining widespread usage. However, due to problems with algorithms currently employed in most cameras, users often experience the following issues while zooming:

●Extreme blurriness
●Shaking
●Slow focus

These problems heavily degrade the user experience. In surveillance monitoring applications, a blurry image which lasts for even a few seconds is enough to cause the loss of important information or evidence, and this fact renders many cameras useless for critical monitoring scenarios.

Dahua PFA technology was created to solve these problems. PFA’s optimized zooming algorithms provide users with clear and steady video throughout the process of zooming, both in daytime and most nighttime scenarios, eliminating the possibility of missing any details.

Slow focus

About PFA Technology

PFA, short for Predictive Focus Algorithm, provides a method to achieve continuous, high-precision focus during the entire zooming process. When the device is zooming, the technology analyzes the AF value curve transformation law under the subject distance curve, and adjusts different subject distances within the depth of focus, unifying the statistics to engage in precise subject distance adjustment, thus achieving clarity throughout the zooming process. PFA technology has innovatively introduced new methods of judgement to ensure the accuracy and predictability of the direction of subject distance adjustment. The result is a set of advanced focusing algorithms.

Comparison of video with and without PFA

Benefits from PFA Technology

● Ensures clarity throughout the process of zooming
Uses statistical analysis to stabilize the scene, enabling the device to preserve a clear image when zooming
● Eliminates shaking during zooming
Real time analysis and seamless adjustment of subject distance built into the algorithm logic allows for a rapid and stable transition from different subject distances.
● Shortens Focus Time
Due to the continuous execution of focusing algorithms throughout the zooming process, the device has already neared optimal focus upon zoom completion. After zooming, only fine incremental adjustments are needed ensure precise focus, thus substantially shortening focus time.

The realization of PFA technology substantially improves user experience and increases product value.