eVision  EasyMatch

- Pattern matching using normalized correlation
- Sub-pixel accuracy
- Rotation and scaling support
- Detection of multiple pattern occurrences
- Support of gray scale and color images
- Support of "don't care" areas

Description

EasyMatch is a gray-level and color pattern matching library. It lets you train the system on a reference pattern and afterwards locate its occurrences in other images. This tool is very convenient when the position of a given part is unknown in the field of view, or if the presence of parts must be controlled. The library works by using normalized correlation method, i.e. measuring discrepancies between the pattern and the target image.

EasyMatch Multiple pattern occurrences

Multiple Pattern Occurences

EasyMatch is able to find several occurrences of a pattern, up to a user-defined number.

EasyMatch Image Correlation

Standard, Offset-Normalized, Gain-Normalized And Fully-Normalized Correlation

The correlation is computed on grey scale or color images. To cope with pattern lighting variations, pattern images are normalized. EasyMatch provides four normalization modes, depending on whether a grey-scale gain and/or offset compensation are used.

EasyMatch Normal inverse or mixed contrast

Normal, Inverse, Or Mixed Contrast

Because of particular lighting effects, an object can appear with inverted contrast (white on black instead of black on white or conversely). Depending on the application, it can be useful to keep inverted instances or to disregard them. Three contrast modes are available: consider positive occurrences only, negative occurrences only or both.

Translation, Rotation, And Isotropic/Anisotropic Scaling

To find the best matches between the pattern and target image, the target is allowed to translate horizontally and vertically. Additionally, it can be allowed to rotate and/or to change its scale in the X and Y directions simultaneously or independently. The rotation angle and scale factors vary in a user-specified interval. All degrees of freedom can be combined at will.

EasyMatch Translation rotation and isotropic anisotropic scaling

Variable Accuracy, Up To Sub-Pixel Level

The accuracy with which the pattern is measured can be chosen (the less accurate, the faster). A one tenth-of-a-pixel accuracy can be achieved.

EasyMatch Variable accuracy up to sub pixel level

Don't Care Pixels

When the pattern cannot be inscribed in a rectangular ROI, the surrounding of the pattern can be ignored by setting the pixels values below a threshold level. These pixels will not take part in the matching process. The same feature can be used if parts of the template change from sample to sample.

EasyMatch dont care

Gray-Level And Color Images

EasyMatch works with 8-bit gray-scale images as well as 24-bit RGB images.

EasyMatch Vision Tool for Color

Non-Square Pixels

When images are acquired with non-square pixels, rotated objects appear skewed. Taking the pixel aspect ratio into account can compensate for this effect.

EasyMatch for Non Square Images

Other Benefits

Neo Licensing System

Neo is the new Licensing System. It is reliable, state-of-the-art, and is now available to store Open eVision and eGrabber licenses. Neo allows you to choose where to activate your licenses, either on a Neo Dongle or in a Neo Software Container. You buy a license, you decide later.

Neo Dongles offer a sturdy hardware and provide the flexibility to be transferred from a computer to another. Neo Software Containers do not need any dedicated hardware, and instead are linked to the computer on which they have been activated.

Neo ships with its own, dedicated Neo License Manager which comes in two flavours: an intuitive, easy to use, Graphical User Interface and a Command Line Interface that allows for easy automation of Neo licensing procedures.

All Open eVision Libraries For Windows And Linux

  • Microsoft Windows 11, 10 for x86-64 (64-bit) processor architecture
  • Microsoft Windows 11, 10 IoT Enterprise on x86_64 systems
  • Linux for x86-64 (64-bit) and ARMv8-A (64-bit) processor architectures with a glibc version greater or equal to 2.18
DriverWinLinuxARM

Open eVision Studio

Open eVision Studio is the evaluation, prototyping and development tool of Open eVision.
Its intuitive graphical user interface allows you to call and immediately see the result of any of eVision’s 2D image processing functions. A scripting functionality generates the corresponding code, which can then be copied and pasted into your application.

Open eVision Studio is free (when using Open eVision 2.0 and above) and does not require any license.

eVision Bundle Studio AVT
eVision Bundle Studio AVT

Software

Host PC Operating System

Open eVision is a set of 64-bit libraries that require an Intel compatible processor with the SSE4 instruction set or an ARMv8-A compatible processor.

Open eVision can be used on the following operating systems:

Microsoft Windows 11, 10 for x86-64 (64-bit) processor architecture

Microsoft Windows 11, 10 IoT Enterprise for x86-64 systems

Linux for x86-64 (64-bit) and ARMv8-A (64-bit) processor architectures with a glibc version greater or equal to 2.18

Remote connections

Remote connections are allowed using remote desktop, TeamViewer or any other similar software.

Virtual machines

Virtual machines are supported. Microsoft Hyper-V, Oracle VirtualBox and libvirt hypervisors have been successfully tested.

Only the Neo Licensing System is compatible with virtualization.

Minimum requirements:

2 GB RAM to run an Open eVision application

8 GB RAM to compile an Open eVision application

Between 100 MB and 2 GB free hard disk space for libraries, depending on selected options.

APIs

Supported programming languages :

The Open eVision libraries and tools support C++, Python and the programming languages compatible with the .NET (C#, VB.NET)

C++ requirements: A compiler compatible with the C++ 11 standard is required to use Open eVision

Python requirements: Python 3.11 or later is required to use the Python bindings for Open eVision

.NET requirements: .NET framework 4.8 (or later) or the .NET platform 6.0 (or later) are supported

Supported Integrated Development Environments:

Microsoft Visual Studio 2017 (C++, C#, VB .NET, C++/CLI)

Microsoft Visual Studio 2019 (C++, C#, VB .NET, C++/CLI)

Microsoft Visual Studio 2022 (C++, C#, VB .NET, C++/CLI)

QtCreator 4.15 with Qt 5.12

Ordering Information

Product status

Released

Product code - Description

PC4153 Open EasyMatch for USB dongle

PC4303 Open eVision EasyMatch

Related products

PC6512 eVision/Open eVision USB Dongle (empty)

PC6514 Neo USB Dongle (empty)

EasyMatch