CAMERA IMAGE QUALITY TUNING

Image quality contains several aspects, and it is not the same thing for all applications. A general-purpose camera product where a human will be the receiver of the image has certain requirements, and items like color rendering, white point balance, uniformity, and noise will be important. If the receiver is a computer vision system, other items like sharpness and contrast may be of higher importance. And then there are countless special cases where other aspects are more important, for example, if the camera is paired with its own specialized infrared light source for night vision, or in a medical application where some selected aspects of the image quality contain all the information needed for diagnosis.

The exact procedure is determined by the SW support functions from the ISP (image signal processing) chipset provider, like for example Chromatix from Qualcomm, which the Sigma team has extensive experience with. The steps needed also vary depending on the exact product use cases, ranging from basic objective tuning in well-known lab environments (where numerical values can be obtained to quantify the image quality), to subjective tuning in real-life use-case specific scenes where the image needs to be evaluated by an experienced camera expert engineer using calibrated reference equipment. Often the subjective testing includes a reference device used to benchmark against. But the general steps are the same for all ISPs, from major chipset providers like Qualcomm/Ambarella/MediaTek/NXP, to camera sensors with its own built-in ISP.

It is important that a project clearly defines all aspects of the desired solution where the camera is to be used. The optoelectronics team members are well experienced to discuss this and help you as a customer specify all use cases. We can also from our broad experience with multiple products help you understand what is possible with different types of state-of-the-art camera technologies.

What camera is most suited to use for your specific use cases? Our team works as camera experts in every project and is in continuous contact with multiple suppliers and we evaluate camera technology daily. This means that we know what camera sensor type would be suitable for You and its strengths and weaknesses. It is also very important to combine a camera sensor with a suitable host chipset to make a good match for optimal performance.

A camera sensor must be paired with a lens suitable for the use cases and the whole module must be developed and manufactured to fit the product. The camera team will help you find a suitable module supplier, specify the module to be made, and evaluate the integration of the camera sensor in the module to find the best performance at the most competitive price. We can also test and benchmark different off-the-shelf modules for the best performance.

How do we ensure that the product is designed and developed to give the best camera performance? The camera team is well experienced in collaborating with all other engineering competencies needed to fulfill the entire product requirements. This would cover all aspects of industrial design, electronics design, mechanical CAD, and SW. We can also support anything from optical simulations of flash LED illumination of the scene, to support the development of custom image processing algorithms if needed.

The camera labs at Sigma Connectivity are used for several steps in the development process. Besides the image quality tuning, the same labs are also used to verify that the prototype is built according to design and expectations. We have many types of specialized equipment to evaluate all aspects of the camera system performance, and we can even design custom-made tests for a specific application.