Trends in Industrial Image Processing
The change from analog to digital technologies in the industrial image-processing (IIP) sector is in full swing. Therefore, the reliable frame grabber appears to be increasingly headed out to pasture. This is because digital communications interfaces such as Gigabit Ethernet, USB and FireWire allow for adequate camera-based solutions without image-capture cards. "Nevertheless the frame grabber will continue to find its niche," says Mathias Leumann, CEO of Leutron Vision AG.
Leumann explains the latest trends in the world of IIP here.
Is there a threat to the existence of the reliable image-capture card since digital cameras with interfaces like FireWire, USB and Gigabit Ethernet push ever more forceful onto the market?
Already at the start the new millennium we could recognize that the market share for classical frame grabbers would fall within the decade. Besides the many existing analog grabbers that operate satisfactorily under the philosophy "Never touch a running system," the classical frame grabber is implemented in new projects primarily when a very short and calculable latency period plays a role in transmission of image data, such as for use with line scanning cameras or for implementation of high-speed cameras. They require data bandwidth from 25 to 70 megabytes per second, which exceeds the bit-serial standards such as USB 2.0, FireWire and Gigabit Ethernet. Add then the CameraLink Standard, which can achieve data-transfer rates up to 680 Mbps. So the classical frame grabber as plug-in card will have to support the CameraLink Standard for a long time to come.
Why are the systems used today in the industrial sphere predominantly based on analog cameras with their respective frame grabbers? Is it because of price?
Analog systems have become well established in the marketplace and are built into many machines. They therefore have achieved a good price-performance ratio. Some developers continue to tend towards analog cameras because they possess a great deal of expertise in this area. However, in our opinion, hardly any reason exists to implement analog cameras on new projects. Just to name a few advantages: with digital image-processing systems you get significantly better image quality, up to 12-bit dynamic range; the camera’s parameters can be set using software; the camera’s availability, as well as its properties, can be maintained remotely; upgrading the camera in the field is easily achieved; and with Power over CameraLink we have succeeded in offering a technically superior digital system for the same price as its analog counterpart.
What does Power over CameraLink (PoCL) mean, and what are its advantages?
Previously the power supply for the CameraLink interface, which had to run on an additional cable or network device, proved to be not fully comfortable. With PoCL the power supply for the camera is made available from the frame grabber via the CameraLink cable.
In the future, if the frame-grabber card finds its niche solely in high-end applications, this will certainly have an effect on the sales volume.
Of course this reduces the sales volume significantly. And the niche will get ever narrower with the increasing performance of the bit-serial interfaces in the cameras. As a result, a frame-grabber manufacturer won’t be able to live on the classical frame-grabber business alone anymore, because the complexity of these devices, both on the hard- and software sides, is very high, and the dwindling unit volumes deliver ever lower profit margins.
What are the major trends given this huge diversity of IIP-based solutions?
Above all the future of IIP will be determined by the digital camera interfaces. During the past year the Gigabit Ethernet Standard was adopted. It promises to provide significant economic advantages when deployed with long cable lengths and middle to high data rates. In addition, Ethernet is already present in many industrial facilities, which brings about additional savings. Common solutions that have consisted of CameraLink camera plus frame grabber will in the future probably be gradually replaced by cost-effective GigE camera systems. A further trend is observable regarding Smart Cameras, which contain a complete image-processing system in a compact camera case. These intelligent cameras are currently exhibiting high growth rates. They are the preferred option to deploy where a strictly defined task is involved and when overall conditions don’t change constantly, such as in quality and integrity control, measurement, code or text recognition or color inspection.
In summary, we expect that in the coming years digital cameras, especially those with a GigE interface to the standard PC, as well as Smart Cameras, will predominate in the IIP market. Of course the best and most sensible solution alternative depends once and for all on the respective job requirements and the existing infrastructure. For this reason, the classical frame-grabber card will continue to find its ‘right to exist’ in the high-end niche for some time to come.