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eVision 26.10.0 documentation
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eVision 26.10.0 documentation
  • What’s New
    • Release notes
      • Release notes 26.10
    • Changelog History
  • Getting Started with eVision
    • Installing eVision
    • Managing your Licenses
    • First Steps with eVision
    • eVision Studio
      • Navigating the Interface
      • Running Tools on Images
      • Displaying Images
      • Working with a Region
    • Neo Licensing System Documentation
      • Using the User Interface
      • Using the Online Command Line
      • Using the Offline Command Line
      • Neo Licensing System FAQ
  • Using eVision
    • Basic Operations
      • Image Operations
        • Pixel Containers and Files
        • Loading a Pixel Container File
        • Saving a Pixel Container File
        • Memory Allocation
        • 3D Rendering of 2D Images
      • Regions and ROIs
        • Regions Of Interest (ROI)
        • Arbitrarily Shaped ROI (ERegion)
        • Flexible Masks
      • Frames and Alignment
      • Common Data Types
        • Vectors
        • Geometrical Shapes
      • Error Reporting
      • Drawing and Graphical Interactions
      • Utility Functions
        • Timing
        • Locating Installation Folders
    • General Purpose Libraries
      • EasyImage - Pre-Processing Images
        • Pixel Operations
          • Intensity Transformation
          • Thresholding
          • Arithmetic and Logic
          • Overlay
        • Filtering
          • Linear Filtering
          • Non-Linear Filtering
          • Noise Reduction and Estimation
          • Gabor Filter
          • Fourier Transform
        • Geometric Operations
          • Geometric Transforms
          • Operations on Interlaced Video Frames
        • Feature Extraction and Statistics
          • Scalar Gradient
          • Canny Edge Detector
          • Harris Corner Detector
          • Vector Operations
          • Computing and Using Image Statistics
          • Straight Line Detector
        • Image Composition
          • HDR Fusion
          • Image Stitching
      • EasyColor - Pre-Processing Color Images
        • Using EasyColor
        • EasyColor - Lookup Table Operations
        • EasyColor - Bayer Conversion
    • Matching and Measurement
      • EasyObject - Analyzing Blobs
        • Process and Workflow
        • EasyObject - Encoding an Image
        • Objects, Holes and their Features
        • Selecting and Sorting Blobs
        • Object Template Matcher
        • EChecker - Validating Golden Templates
      • EasyGauge - Measuring down to Sub-Pixel
        • Principles of EasyGauge
        • Gauge Types
        • Measurement and Fitting Parameters
        • Advanced Usage
        • Display and Graphical Manipulation
        • Differences with the Legacy API
        • Legacy EasyGauge
          • Workflow
          • Gauge Definitions
          • Find Transition Points Using Peak Analysis
          • Find Shapes Using Geometric Models
          • Gauge Manipulation: Draw, Drag, Plot, Group
          • Calibration and Transformation
          • Calibration Using EWorldShape
          • The Calibration Model
          • Unwarp an Image
      • EasyFind - Matching Geometric Patterns
        • Purpose and Principles
        • Learn a Pattern from Image(s)
        • Learn a Pattern from Vectors
        • Find Matches
      • EasyMatch - Matching Area Patterns
        • Learn a Pattern
        • Find Matches
    • Text and Code Reading
      • EasyBarCode - Reading Bar Codes
        • Using EasyBarCode
        • EasyMailBarCode - Reading Mail Bar Codes
        • EasyBarCode1 - Reading Bar Codes (deprecated)
      • EasyDeepOCR - Reading Texts with Deep Learning
        • EasyDeepOCR Principles and Workflow
        • EasyDeepOCR Detailed Usage
        • EasyDeepOCR Setting the Parameters
        • EasyDeepOCR Retraining a Model
      • EasyOCR - Reading Texts
        • Using EasyOCR
      • EasyOCR2 - Reading Complex Texts
        • Using EasyOCR2
        • EasyOCR2 Advanced Parameters
      • EasyMatrixCode - Reading Matrix Codes
        • Specifications and Supported Symbols
        • Using EasyMatrixCode
        • EasyMatrixCode1 (deprecated)
          • Specifications
          • Supported Symbols
          • Workflow
          • Learning a Matrix Code
          • Computing the Print Quality
          • Using GS1 Data Matrix Codes
      • EasyQRCode - Reading QR Codes
        • Specifications
        • Using EasyQRCode
      • ECodeReader - Unified Interface
      • List of Supported Codes
      • Code Grading
        • ISO/IEC 15416 for 1D Bar Codes
        • ISO/IEC 15415 for Data Matrix and QR Codes
        • ISO/IEC 29158 for Data Matrix and QR Codes
        • SEMI T10-0701 for Data Matrix Codes
      • Comparison of OCR methods
    • Deep Learning Inspection
      • Deep Learning Studio
      • Workflow
        • Choose Your Tool
        • Managing the Dataset and the Annotations
        • Managing the Dataset Splits
        • Using Data Augmentation
        • Training a Deep Learning Tool
        • Using a Deep Learning Tool
        • Benchmarking a Deep Learning Tool
      • Execution Settings and Hardware Support (CPU/GPU)
      • Specifications
      • EasyClassify - Multi-label Image Classification
      • EasySegment - Detecting and Segmenting Defects
        • EasySegment Unsupervised
        • EasySegment Supervised
      • EasyLocate - Locating Objects and Defects
    • 3D Processing
      • Easy3D - Tools for 3D Object Processing
        • Base Types
        • Depth Maps
        • Point Clouds
        • Meshes
        • ZMaps
        • 3D Filters and Statistics
        • 3D Viewer
        • Photometric Stereo
      • Easy3DLaserLine - Laser Line Extraction and Calibration
        • Laser Triangulation and Extraction
        • Line Extraction Benchmark
        • Calibration
      • Easy3DObject - Extracting 3D Objects
        • Object Features
        • Extracting and Using Objects
      • Easy3DMatch - 3D Alignment and Comparison
        • Alignment, Comparison and Matching
        • 3D Sensor Fusion
    • Live Image Acquisition
      • EGrabberBridge - Using Images from eGrabber Sources
      • VimbaXBridge - Using Images from VimbaX Sources
    • Advanced Operations
      • Camera Calibration
        • Calibration Modes and Models
        • Computing the Calibration Model
        • Unwarping an Image
      • Multicore Processing
    • Applicative Processing (Discontinued)
      • EasySpotDetector - Detecting Spots with Deep Learning
        • Using EasySpotDetector
  • Resources
    • Code Snippets
      • Basic Operations Code Snippets
        • Basic Types Code Snippets
          • Calibration Code Snippets
            • Dot Grid-Based Calibration Code Snippet
            • Landmark-Based Calibration Code Snippet
            • Calibration by Guesswork Code Snippet
            • Coordinates Transform Code Snippet
            • Image Unwarping Code Snippet
          • Loading and Saving Images Code Snippet
          • Interfacing Third-Party Images Code Snippet
          • Retrieving Pixel Values Code Snippet
          • Importing Bitmap from the Resources Code Snippet
          • ROI Placement Code Snippet
          • Vector Management Code Snippet
          • Exception Management Code Snippet
        • ERegion Code Snippets
          • Basic Usage of Region Code Snippet
          • Preparing a Region Code Snippet
          • Combining Regions Code Snippet
          • Converting a Result to a Region Code Snippet
      • General Purpose Libraries Code Snippets
        • EasyImage Code Snippets
          • Thresholding Code Snippets
            • Single Thresholding Code Snippet
            • Double Thresholding Code Snippet
            • Histogram-Based Single Thresholding Code Snippet
            • Histogram-Based Double Thresholding Code Snippet
          • Arithmetic and Logic Operations Code Snippet
          • Convolution Code Snippets
            • Pre-Defined Kernel Filtering Code Snippet
            • User-Defined Kernel Filtering Code Snippet
          • Non-Linear Filtering Code Snippets
            • Morphological Filtering Code Snippet
            • Hit-and-Miss Transform Code Snippet
          • Vector Operations Code Snippets
            • Path Sampling Code Snippet
            • Profile Sampling Code Snippet
          • Statistics Code Snippets
            • Image Statistics Code Snippet
            • Sliding Windows Statistics Code Snippet
            • Histogram-Based Statistics Code Snippet
          • Noise Reduction by Integration Code Snippets
            • Temporal Noise Reduction Code Snippet
            • Recursive Average Code Snippet
          • Feature Point Detectors Code Snippets
            • Harris Corner Detector Code Snippet
            • Canny Edge Detector Code Snippet
          • Using an ERegion Code Snippet
          • Warping Code Snippets
            • Performing a Ring Warping Code Snippet
            • Performing an Inverse Warping Code Snippet
          • Fourier Transform Code Snippets
            • Performing a Direct Fourier Transform Code Snippet
            • Performing an Inverse Fourier Transform Code Snippet
          • HDR Fusion Code Snippets
            • Performing a HDR Fusion Using the Default Algorithm Code Snippet
            • Performing a HDR Fusion Using Specific Algorithms Code Snippet
            • Changing the HDR Fusion Algorithm or its Parameters Code Snippet
          • Performing a Resize Operation Code Snippet
          • Image Stitching Code Snippets
            • Basic Image Stitching Code Snippet
            • Image Stitching with a Reference Image Code Snippet
            • Incremental Image Stitching Code Snippet
            • Image Stitching with Learning Code Snippet
          • Gabor filter Code Snippet
          • Scalar Gradient Code Snippet
          • Overlay Code Snippet
          • Intensity Transformation Code Snippets
            • Normalization Code Snippet
            • Normalization using a LUT Code Snippet
        • EasyColor Code Snippets
          • Colorimetric Systems Conversion Code Snippet
          • Color Components Code Snippet
          • White Balance Code Snippet
          • Pseudo-Coloring Code Snippet
          • Bayer Pattern Decoding Code Snippet
      • Matching and Measurement Code Snippets
        • EasyObject Code Snippets
          • Image Segmenter Code Snippet
          • Continuous Mode Code Snippet
          • Holes Extraction Code Snippet
          • Computing Blobs Features Code Snippet
          • Looping over the runs of an object Code Snippet
          • Selecting and Sorting Blobs Code Snippet
          • Using the Object Template Matcher Code Snippet
          • EChecker Code Snippets
            • EChecker with a Single Image Code Snippet
            • EChecker with Multiple Images Code Snippet
        • EasyMatch Code Snippets
          • Pattern Learning Code Snippet
          • Setting Search Parameters Code Snippet
          • Pattern Matching and Retrieving Results
          • Pattern Learning with ERegion Code Snippet
        • EasyFind Code Snippets
          • Pattern Learning Code Snippet
          • Setting Search Parameters Code Snippet
          • Pattern Finding and Retrieving Results Code Snippet
          • Learning Using a DXF File Code Snippet
          • EasyFind Legacy API Code Snippets
            • Learning Using an EPolygonShape Code Snippet (Legacy)
        • EasyGauge Code Snippets
          • Point Location Code Snippet
          • Line Fitting Code Snippet
          • Circle Fitting Code Snippet
          • Rectangle Fitting Code Snippet
          • Wedge Fitting Code Snippet
          • Gauge Grouping Code Snippets
            • Complex Gauge Measurement Code Snippet
            • Legacy EasyGauge Gauge Grouping Code Snippets
              • Complex Gauge Measurement Code Snippet (Legacy)
              • Gauge Hierarchy Code Snippet (Legacy)
          • Calibration using EWorldShape Code Snippets (Legacy)
            • Calibration by Guesswork Code Snippet (Legacy)
            • Landmark-Based Calibration Code Snippet (Legacy)
            • Dot Grid-Based Calibration Code Snippet (Legacy)
            • Coordinates Transform Code Snippet (Legacy)
            • Image Unwarping Code Snippet (Legacy)
          • Legacy EasyGauge Code Snippets
            • Point Location Code Snippet (Legacy)
            • Line Fitting Code Snippet (Legacy)
            • Circle Fitting Code Snippet (Legacy)
            • Wedge Fitting Code Snippet (Legacy)
            • Rectangle Fitting Code Snippet (Legacy)
      • Text and Code Reading Code Snippets
        • EasyBarCode Code Snippets
          • Reading a Bar Code Code Snippet
          • Reading a Bar Code Following a Given Symbology Code Snippet
          • Reading a Grid of Bar Codes Code Snippet
          • Learning a Bar Code Code Snippet
          • Grading a Bar Code Code Snippet
          • Reading a Mail Bar Code Code Snippet
          • Reading a Bar Code Code Snippet
          • Reading a Bar Code Following a Given Symbology Code Snippet
          • Reading a Bar Code of Known Location Code Snippet
        • EasyDeepOCR Code Snippets
          • Reading a Text Code Snippet
          • Get Score Code Snippet
          • Specifying a Topology Code Snippet
          • Building a Sample List Code Snippet
          • Performing an Optimization Code Snippet
          • Splitting the Pipeline Code Snippet
          • Training and Using a Custom Model Code Snippet
        • EasyOCR Code Snippets
          • Learning Characters Code Snippet
          • Recognizing Characters Code Snippet
        • EasyOCR2 Code Snippets
          • Detecting Characters Code Snippet
          • Learning Characters Code Snippet
          • EasyOCR2 Reading Characters Code Snippets
            • Reading Using TrueType Fonts Code Snippet
            • Reading Using EOCR2 Character Database Code Snippet
            • Reading Using EOCR2 Model File Code Snippet
          • View Bitmap Code Snippet
        • EasyMatrixCode Code Snippets
          • Reading Data Matrix Codes Code Snippet
          • Learning a Data Matrix Code Code Snippet
          • Reading a Grid of Matrix Codes Code Snippet
          • Grading a Data Matrix Code Code Snippet
          • Reading Matrix Codes from Several Images Using Asynchronous Processing Code Snippet
          • Reading a Data Matrix Code Code Snippet
          • Learning a Data Matrix Code Code Snippet
          • Tuning the Search Parameters Code Snippet
          • Grading a Data Matrix Code Code Snippet
        • EasyQRCode Code Snippets
          • Reading QR Codes Code Snippet
          • Grading a QR Code Code Snippet
          • Reading a Grid of QR Codes Code Snippet
          • Retrieving Information of a QR Code Code Snippet
          • Tuning the Search Parameters Code Snippet
          • Retrieving the Decoded String Code Snippet (Simple)
          • Retrieving the Decoded String Code Snippet (Safe)
          • Retrieving the Decoded Data Code Snippet (Advanced)
        • ECodeReader Code Snippets
          • Reading a set of Code Code Snippet
      • Deep Learning Libraries Code Snippets
        • EasyClassify Code Snippets
          • Creating a Dataset and Training a Classifier Code Snippet
          • Learning Out Of Distribution parameters in a previously trained classifier Code Snippet
          • Loading a Classifier and Classifying a New Image Code Snippet
          • Using Multithreading for Classification Code Snippet
          • Using Out Of Distribution scores during classification Code Snippet
        • EasySegment Code Snippets
          • Creating a Dataset and Training a Supervised Segmenter Code Snippet
          • Creating a Dataset and Training an Unsupervised Segmenter Code Snippet
          • Loading a Supervised Segmenter and Segmenting an Image Code Snippet
          • Loading an Unsupervised Segmenter and Segmenting an Image Code Snippet
        • EasyLocate Code Snippets
          • Creating a Dataset and Training a Locator Code Snippet
          • Loading a Locator and Locating Objects on a New Image Code Snippet
      • 3D Processing Libraries Code Snippets
        • Easy3D Code Snippets
          • Using EFilters to Remove the Noise on a ZMap Based on the Standard Deviation Code Snippet
          • Using EFilters to Remove the Noise on a ZMap Based on the Derivation from Neighborhood Code Snippet
          • Aligning Point Clouds Code Snippet
          • Reducing the Size of a Cloud with Random Decimation Code Snippet
          • Reducing the Size of a Cloud with Grid Decimation Code Snippet
          • Using Photometric Stereo Code Snippet
          • Using Flat Images to Improve Photometric Stereo Code Snippet
          • Performing Plane Leveling on Point Clouds Code Snippet
          • Performing ZMap Leveling Code Snippet
          • Using an ERegion to Crop a ZMap Code Snippet
          • Add an Attribute to an EPointCloud with Initial Data Code Snippets
          • Add an Attribute to an EPointCloud without Initial Data Code Snippet
          • Retrieve an Attribute from an EPointCloud Code Snippet
        • Easy3DLaserLine Code Snippets
          • Object-Based Calibration Code Snippet
          • Load Object-Based Calibration Model Code Snippet
        • Easy3DMatch Code Snippets
          • E3DAligner Minimal Code Snippet
          • E3DAligner Reprojection Plane Code Snippet
          • E3DAlignment Align Code Snippet
          • E3DComparer Minimal Code Snippet
          • E3DComparer Advanced Code Snippet
          • E3DMatcher Minimal Sample
          • E3DMatcher Advanced Code Snippet
          • EPointCloudMerger Sample
        • Easy3DObject Code Snippets
          • Extracting 3D Objects with a Selection Criterion Code Snippet
          • Inspecting a Feature from the List of E3DObjects Code Snippet
          • Drawing 2D Features from a List of E3DObjects Code Snippet
          • Drawing 3D Features from a List of E3DObjects Code Snippet
      • Applicative Processing Libraries Code Snippets
        • EasySpotDetector Code Snippets
          • Detect Spots Code Snippet
          • Detect Scratches Code Snippet
          • Detect and Classify Spots Code Snippet
      • Live Image Acquisition Code Snippets
        • EGrabberBridge Code Snippets
          • Using EGrabberBridge Code Snippet
          • Using EGrabberBridge with Format Conversion Code Snippet
          • Managing EGrabber Parameters Code Snippet
          • Using EGrabber Discovery Code Snippet
        • VimbaX Bridge Code Snippets
          • Using VimbaXBridge Code Snippet
    • Sample Programs
      • Image Processing Sample Programs
        • Basic Sample Program
        • BasicWPF Sample Program
        • ConsoleBasic Sample Program
        • Region Sample Program
        • RegionFreeHand Sample Program
        • EasyImageFilter Sample Program
        • FourierFiltering Sample Program
        • EasyColorComponent Sample Program
        • EasyHDRFusion Sample Program
        • EGrabberBridge Sample Program
        • SharedLibraryConsole Sample Program
      • 3D Processing Sample Programs
        • Easy3DViewer Sample Program
        • Easy3DViewerWPF Sample Program
        • Easy3DPhotometricStereo Sample Program
        • Easy3DPointCloudToMesh Sample Program
        • Easy3DZMapGenerator Sample Program
        • Easy3DProcessing2D Sample Program
        • Easy3DMultiViews Sample Program
        • Easy3DPCBWarpage Sample Program
        • Easy3DCoaxlinkLLE Sample Program
        • Easy3DLaserLineCalibration Sample Program
        • Easy3DLaserLineExtract Sample Program
        • Easy3DObjectExtract Sample Program
        • Easy3DMatchMatch Sample Program
        • Easy3DMatchAlign Sample Program
        • Easy3DMatchPointCloudMerger Sample Program
      • Matching and Measurement Sample Programs
        • EasyGaugeBasic Sample Program
        • EasyGaugeRegion Sample Program
        • EasyGaugePolygon Sample Program
        • EasyFindLearn Sample Program
        • EasyFindVectorLearn Sample Program
        • EasyMatchLearn Sample Program
        • EasyObjectEChecker2 Sample Program
        • EasyObjectInertia Sample Program
      • Deep Learning Inspection Sample Programs
        • EasyClassifyTrain Sample Program
        • EasyClassifyInference Sample Program
        • EasyClassifyMultiThreadInference Sample Program
        • EasySegmentSupervisedTrain Sample Program
        • EasySegmentSupervisedInference Sample Program
        • EasySegmentSupervisedMultiThreadInference Sample Program
        • EasySegmentUnsupervisedTrain Sample Program
        • EasySegmentUnsupervisedInference Sample Program
        • EasyLocateTrain Sample Program
        • EasyLocateInference Sample Program
        • EasyLocateMultiThreadInference Sample Program
      • Text and Code Reading Sample Programs
        • EasyCodeReading Sample Program
        • EasyBarCodeRead Sample Program
        • EasyBarCodeReadMail Sample Program
        • EasyMatrixCodeRead Sample Program
        • EasyQRCodeRead Sample Program
        • EasyOcrRead Sample Program
        • EasyOcr2Read Sample Program
        • EasyDeepOCRRead Sample Program
        • EasyDeepOCRReadConsole Sample Program
      • Applicative Processing Tools Sample Programs
        • EasySpotDetector Sample Program
      • Python Specific Sample Programs
        • egrabber_acquisition Sample Program
        • openCV_acquisition (OpenCV Camera Acquisition) Sample Program
        • easy3d_viewer Sample Program
        • easy_find_learn Sample Program
        • easy_gauge_basic Sample Program
        • vimbax_acquisition Sample Program
        • Base Web Sample Program
        • Basic Tkinter Sample Program
    • Application Examples
      • Inspecting Fuses
      • Inspecting Pads Using Regions
      • Checking Lot Codes and Mixing with OCR
      • Measuring a Remote Controller
      • Inspecting a PCB
      • Measuring the Warpage of a PCB
  • Download eVision

Api Documentation

  • C++ Api Documentation
  • .NET Api Documentation
  • Python API Documentation
  • Library API Guide
    • Base Classes API Guide
      • Easy Class API Guide
      • Image and ROI Classes API Guide
      • Region Classes API Guide
    • General Purpose API Guide
      • EasyImage API Guide
      • EasyColor API Guide
    • Matching and Measurement API Guide
      • EasyObject API Guide
        • EasyObject API Guide (Legacy)
      • EasyMatch API Guide
      • EasyFind API Guide
      • EasyGauge API Guide
        • EasyGauge API Guide (Legacy)
    • Text and Code Reading API Guide
      • EasyBarCode API Guide
      • EasyDeepOCR API Guide
      • EasyOCR API Guide
      • EasyOCR2 API Guide
      • EasyMatrixCode API Guide
      • EasyQRCode API Guide
    • Deep Learning API Guide
      • EasyClassify API Guide
      • EasySegment API Guide
      • EasyLocate API Guide
    • 3D Processing API Guide
      • Easy3D API Guide
      • Easy3DLaserLine API Guide
      • Easy3DMatch API Guide
      • Easy3DObject API Guide
    • Applicative Processing API Guide
      • EasySpotDetector API Guide
  • Deprecation History

About

  • Conventions
    • Image and Depth Map Buffer
    • Image Coordinate Systems
    • Conventions for Strings
    • eVision Version Numbering
  • Glossary
  • Third Party Licenses
  • Open eVision Documentation
  • About Documentation
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Fourier Transform Code Snippets¶

  • Performing a Direct Fourier Transform Code Snippet
  • Performing an Inverse Fourier Transform Code Snippet
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Performing a Direct Fourier Transform Code Snippet
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