Research and Implementation of Digital Camera Auto Focus Algorithm
The AF (Auto-Focusing) function is one of the most important functions of a digital camera because the quality of the output image is directly dependent on the performance of the focusing system.
The existing digital camera autofocus algorithm consists of two parts, one is a focus operator and the other is a search algorithm. The search optimization algorithm generally uses the mountaineering search HCS algorithm. The HCS algorithm includes three modes: search mode, calibration mode and wait-and-see mode. The conventional HCS algorithm uses three focus modes with the same focus operator, and the focus accuracy is not high enough.
The hM operator has the characteristics of good anti-noise performance and sharp sharpness near the focus point, and the VAR operator has the characteristics of rapid change from the point of convergence.
Using these two characteristics, a new HCS algorithm is proposed: the VAR operator is used in the search mode, and the FS WM operator is used in the calibration mode and the wait-and-see mode.
The experimental results show that the performance of the new HCS algorithm is much better than the conventional HCS algorithm, which improves the focusing accuracy.
The existing digital camera autofocus algorithm has many disadvantages: the time required for focusing is long, and the focusing accuracy is not high enough. A new, completely different autofocus algorithm from existing digital cameras: Just three images move the lens closer to the focus point and then use the HCS algorithm for precise focus.
The main function of the software is to find the clearest image in a series of test images: and provide a variety of focus operators, conventional HCS algorithms and new HCS algorithms, existing autofocus algorithms and new automatic The choice of the focus algorithm. The modular C source code can be easily ported and used in other developments, and has certain practical application value.