The quality of machine vision fluctuates with speed, accuracy, and reliability. Whereas previously the illumination and measurement setup were crucial parameters of each application, today software increasingly becomes the key component for machine vision. First class software today is able to compensate weaknesses of the hardware or the setup, which was not possible some years ago. To solve these challenging tasks, HALCON 7.1 provides more than 1150 operators.
In the tradition of all previous versions, HALCON 7.1 can also be seen as a protection of investment: HALCON 7.1 is hardware-independent, and thus, compatible with many operating systems. Furthermore, HALCON 7.1 provides interfaces to more than 50 frame grabbers and hundreds of industrial cameras.
Innovations in HALCON 7.1
Like previous versions, version 7.1 offers new operators and technologies that are either new on the world market or at least unique in terms of speed and accuracy. The most important innovations are described below:
Data code reader PDF417
PDF417 codes, typically used for Electronic Data Interchange (EDI), are increasingly popular. The high data capacity of facilitates replacing paper documents such as manifests or bills of lading. EDI, the linking of databases between a supplier and customer, provides real-time information about a shipment to the recipient. A manufacturer can then know exactly when critical components will be arriving for the assembly of a product.
– The benefit of HALCON 7.1: HALCON’s PDF417 reader is robust to occlusions and to poor print quality, invariant to image contrast and to rotation, and allows simultaneous detection of multiple PDF417 instances.
Automatic Parameter Determination
Matching is a widely used method in machine vision. The advanced matching (shape- and component-based matching) of HALCON 7.0 was already unique, but automatic parameter determination now eases the matching and can be used for following applications: alignment, completeness checks, inspection, measuring and comparison, position recognition, print inspection, recognition of objects, and shape recognition.
– The benefit of HALCON 7.1: The automatic parameter determination can help new users by needing less time to learn how to use the matching. Inexperienced programmers can develop their application faster.
Line Scan Camera Calibration
HALCON’s 3D camera calibration for area scan cameras for area scan cameras was already a unique feature. MVTec now offers the same technology also for line scan cameras under HALCON 7.1. Thus, this advantageous and frequently used feature is also available where line scan cameras are used for inspection e.g., in the automotive, print, semiconductor, food and beverage, wood and timber industry, and other production processes in which conveyor belts are being used.
– The benefit of HALCON 7.1: With the 3D camera calibration – now also for line scan cameras, the interior camera parameter and pose are determined and pixel coordinates can be converted into world coordinates. Thus, robot control becomes easier. For highly accurate and flexible measurements, calibration is essential.
Gray Value Calibration
Gray value calibration is a preprocessing step that can lead to higher
accuracy in all subpixel processing methods (point finders, measurements, line and edge extraction).
– The benefit of HALCON 7.1: No complex calibration plate is necessary, no 3D camera calibration and no optimized illumination is required.
Speedup of Filters and Arithmetic Operations
For MVTec, it is very important to further increase the speed of machine vision software processing. MMX (Multi Media Extension) is an instruction set designed by Intel to accelerate the processing of large integer data sets as of video, audio, or image data files.
– The benefit of HALCON 7.1: Now, all filters using MMX additionally advance in speed by HALCON 7.1. Now, frequently used filters are faster by 300% to 400%(!).
Normally, 3D calibration needs a set of images showing a calibration plate in various positions and orientations. Self calibration makes this procedure dispensable. The camera parameters can be calculated simply by rotating the camera.
– The benefit of HALCON 7.1: Self calibration allows to automatically derive the camera parameters by just providing several images from an arbitrary scene in which the camera is rotated around its optical center. Self calibration also improves mosaicking (image stitching), because now it is possible even to generate a 360° panorama image.
As calibration data, uncalibrated stereo only needs the interior camera parameters. While classical stereo calibration needs the precise geometric pose of two cameras, this method only needs images of the two cameras.
– The benefit of HALCON 7.1: Uncalibrated stereo is revolutionary for robotics, surveillance and security, where cameras are positioned at widely differing positions, and thus, traditional calibrations are quite cumbersome.
3D Position of Circles
Normally, determining the 3D position of objects requires 2 cameras. By extracting and measuring circles (e.g., drill holes) in workpieces, their 3D position can be determined with only one camera.
– The benefit of HALCON 7.1: Provided that the diameter and the camera parameters are known, HALCON 7.1 can determine the 3D orientation based on the geometric distortion from only one image.
64 Bit Technology under Windows
The new HALCON 7.1 version runs natively under Microsoft Windows XP Professional x64 Edition. Consequently, the large Windows user community can enjoy the large speed-up that Linux have known for quite some time.
– The benefit of HALCON 7.1: Not only the underlying machine vision algorithms profit from faster execution by using 64 bit processor registers: With Windows XP x64 Edition now also machine vision solutions that require more than 2 GB memory per process can be realized. Compared to the 32 bit version, the computing time is reduced by up to 30%.
AOP (Automatic Operator Parallelization)
Driven by the high amount of data throughput of every machine vision application, the possibility to split the processing into several threads that run on different processors has been used for a long time. This is called multi-threading. HALCON automates the data splitting to multiple processors (Parallel HALCON), a task that the programmer has to solve with other systems. AOP was already supported by HALCON 6.0. Nevertheless, this feature is of great use with the brand-new generation of multi core CPUs now coming into market.
– The benefit of HALCON 7.1: After splitting the input data, AOP distributes the data to the available CPUs to process them. Subsequently, the computed data are merged automatically to achieve the same results that are obtained with a single processor. All this is done without any extra work by the programmer. In fact, this automation yields a performance comparable to manually programmed multi-threading, but at the same time brings many benefits: It is much easier to use, it is not error-prone, and also programmers with little multi-threading experience can immediately use it.
MVTec Software GmbH