How to choose a high-definition IP surveillance camera chip solution

2011 was the year of the explosion of high-definition products in the surveillance field. The words "high-definition" and "IP" became well-deserved popular words. More and more manufacturers joined this field, making the high-definition IP cake bigger and bigger. After the concept and promotion, digital high-definition network cameras have gradually been recognized by customers. The digitization, intelligence, high-definition and networking of security products is an irreversible trend. High-definition products on the market are emerging in front of users like mushrooms after rain. At present, there are many high-definition IP solutions on the market, including HiSilicon, TI, NXP, Trident, Techwell, Zhiyuan and many other chip manufacturers have proposed high-definition IP solutions with their own characteristics. How to choose a high-definition IP solution that suits you has become a very concerned issue.

HD IP Solution

Although there are many solutions for high-definition network cameras on the market, from the perspective of architecture, there are only two basic architectures:

Adopt CCD/CMOS sensor

(SENSOR) is used as an image acquisition device and is equipped with an ISP SOC chip. This type of solution has obvious cost advantages. The imaging effect of this solution mainly depends on the ISP (such as 3A, wide dynamic, etc.) integrated by the chip manufacturer. An obvious advantage of adopting this solution is that it is more flexible and can be customized according to the characteristics of the solution, such as snapshot, low frame rate, etc.

It uses front-end camera module

(Cell, such as Hitachi's SC110, SONY's H11) as an image acquisition device, with an ASIC or DSP for encoding, compression and transmission. This type of solution is relatively expensive. Due to the use of professional imaging modules, the original image effect is good, so the effect of the entire IPC product depends largely on the effect of the supporting compression and transmission module. The main indicators are the clarity and real-time performance of the compressed image. In addition to the above architecture, for security manufacturers, choosing solutions that meet the development direction of their own products based on different market demands and product positioning is a dilemma faced by every equipment manufacturer. When choosing a solution, the following aspects need to be considered:

Storage and bandwidth usage

The increase in image resolution will inevitably consume more bandwidth and storage space. Taking 1920X1080@30 frames as an example, using the H.264 encoding algorithm, to ensure clarity, the bit rate needs to be controlled at around 6Mbps, so 2.7GB of storage space is required per hour. In an ordinary LAN environment, 100M bandwidth can only reliably transmit 10 channels of encoded video, and a 1T hard drive can only store about 400 hours. How to balance storage and bandwidth is a difficult problem facing manufacturers.

Clear lens performance

The improvement of image resolution has put forward new requirements for lens accuracy and horizontal control. The resolution of 2MP network cameras is more than ten times that of PAL. However, the technology used in ordinary high-definition DC or DV is expensive to use in security products, which is not conducive to the promotion of network high-definition cameras. How to lower the threshold of imaging system is the key factor in the development of network high-definition cameras.

3A control technology

In analog cameras, various manufacturers have made relatively perfect 3A control technologies such as auto focus, white balance, and auto exposure, but the application of these technologies in digital high-definition cameras is relatively weak. 3A control is very important for high-definition image quality. At present, there is relatively little experience in the control algorithms involved in these technical fields in China. Especially in high-definition systems, the increase in resolution will increase the corresponding algorithm overhead. How to ensure the real-time and fast completion of these control algorithms is very important.

Chip Solutions

The most mainstream HD IP solution on the market is HiSilicon. From Hi3512, Hi3515 to the latest Hi3516, HiSilicon provides a complete set of HD solutions. Taking Hi3512 as an example, this solution is based on the ARM9 processor core and the high-performance communication media processor of the video hardware acceleration engine. It has the advantages of high integration, programmability, and support for multiple protocols such as H.264 and MJPEG. The video processing unit can support H.264 Main Profile, Baseline, Profile, MJPEG, JPEG and other protocols for encoding and decoding; support 1.3M Pixels@30fps , support JPEG capture with a maximum of 3 million pixels; the video processing unit can also support dual-stream encoding and other functions. The rich peripheral interfaces of the Hi3512 solution are convenient for meeting equipment specification requirements and effectively reducing the BOM cost of the entire machine.