CalculateRegion Method

Summary

Populates the region for each object using its outline points.

Syntax

Objective-C

C++/CLI

Java

Python

public void CalculateRegion( 
   ICollection<ExObjObject> objects, 
   ExObjRegionOptions options 
)

- (void)calculateRegion:(NSEnumerator<LTExObjObject *> *)objects withOptions:(LTExObjRegionOptions *)options;

public void calculateRegion( 
   java.util.Collection<ExObjObject> objects, 
   ExObjRegionOptions options 
);

public:  
   void CalculateRegion( 
      ICollection<ExObjObject^>^ objects, 
      ExObjRegionOptions^ options 
   )

def CalculateRegion(self,objects,options):

Parameters

objects

The objects to process. This value cannot be null.

options

Additional options. This value cannot be null.

Remarks

If ExObjObject.Siblings is populated, this method will properly handle the additional objects during calculation.

Example

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.ImageProcessing; 
using Leadtools.ImageProcessing.Core; 
 
public void ExtractObjectsCommandExample() 
{ 
   using (RasterCodecs codecs = new RasterCodecs()) 
   // Load the original image 
   using (RasterImage inputImage = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "demoicr2.tif"))) 
   { 
      // Setup the extraction options 
      ExtractObjectsCommand command = new ExtractObjectsCommand() 
      { 
         DetectChildren = true, 
         EightConnectivity = true, 
         Outline = true 
      }; 
 
      // Extract the objects 
      command.Run(inputImage); 
 
      using (ExObjData data = command.Data) 
      { 
         // Log the number of objects from the first list 
         ExObjObjectList objects = data[0].Objects; 
         Console.WriteLine($"Number of objects (before filtering): {objects.Count}"); 
 
         // Log the number of points around the first object (braces for scope) 
         { 
            int count = 0; 
            foreach (ExObjOutlinePoint point in objects.First().Outline) 
               count++; 
            Console.WriteLine($"First object's outline length: {count}"); 
         } 
 
         // Setup the filter options 
         ExObjFilterOptions filterOptions = new ExObjFilterOptions() 
         { 
            LargeObjectThreshold = -1, // No upper limit on size 
            SmallObjectThreshold = 10 // Remove objects smaller than 10x10 pixels 
         }; 
 
         // Filter the objects 
         data.FilterList(objects, filterOptions); 
 
         // Log the number of objects again 
         Console.WriteLine($"Number of objects (after filtering): {objects.Count}"); 
 
         // Setup the content bound options 
         ExObjContentBound contentBound = new ExObjContentBound(new LeadRect(192, 260, 323, 146)); 
         ExObjContentBoundOptions contentBoundOptions = new ExObjContentBoundOptions() 
         { 
            ObjectsOfInterest = null // Pass null to use every object in data 
         }; 
 
         // Calculate the content bounds 
         data.CalculateContentBound(new ExObjContentBound[] { contentBound }, contentBoundOptions); 
 
         // Setup the region options 
         ExObjRegionOptions regionOptions = new ExObjRegionOptions() 
         { 
            Horizontal = true 
         }; 
 
         // Calculate each object's region 
         data.CalculateRegion(objects, regionOptions); 
 
         // Create an output image 
         using (RasterImage outputImage = RasterImage.Create(inputImage.Width, inputImage.Height, 24, inputImage.XResolution, RasterColor.White)) 
         { 
            // Fill the output image with white 
            new FillCommand(RasterColor.White).Run(outputImage); 
 
            // Draw the content bound rects for the first word. Red for the input, green for the output. 
            outputImage.AddRectangleToRegion(null, contentBound.Input, RasterRegionCombineMode.Set); 
            new FillCommand(new RasterColor(255, 0, 0)).Run(outputImage); 
            outputImage.AddRectangleToRegion(null, contentBound.Content, RasterRegionCombineMode.Set); 
            new FillCommand(new RasterColor(0, 255, 0)).Run(outputImage); 
 
            // Populate the output image with each object's region 
            foreach (ExObjObject @object in objects) 
               foreach (ExObjSegment segment in @object.RegionHorizontal) 
               { 
                  // Update the region to the current segment 
                  outputImage.AddRectangleToRegion(null, segment.Bounds, RasterRegionCombineMode.Set); 
 
                  // Fill the region with black 
                  new FillCommand(RasterColor.Black).Run(outputImage); 
               } 
 
            // Clear the output image's region 
            outputImage.MakeRegionEmpty(); 
 
            // Save the output image 
            codecs.Save(outputImage, Path.Combine(LEAD_VARS.ImagesDir, "ExtractObjects.png"), RasterImageFormat.Png, 0); 
         } 
      } 
   } 
} 
 
static class LEAD_VARS 
{ 
   public const string ImagesDir = @"C:\LEADTOOLS22\Resources\Images"; 
}

Requirements

Target Platforms

Reference

ExObjData Class

ExObjData Members

Leadtools.ImageProcessing.Core Namespace

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Help Version 22.0.2023.11.1

Leadtools.ImageProcessing.Core Assembly

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