GetBlockLeft Method (GdPictureSegmenter)

In This Topic

Returns the left x-coordinate of the bounding box of the specified block, that is a part of the segmentation result specified by its index.

This method uses a coordinate system, where the origin is in the top-left corner of the processed image and the units are pixels.

Syntax

Visual Basic
C#
Delphi
JScript
Managed Extensions for C++
C++/CLI

'Declaration
 
Public Function GetBlockLeft( _
   ByVal SegmentationResultID As String, _
   ByVal BlockIdx As Integer _
) As Integer

public int GetBlockLeft( 
   string SegmentationResultID,
   int BlockIdx
)

public function GetBlockLeft( 
    SegmentationResultID: String;
    BlockIdx: Integer
): Integer;

public function GetBlockLeft( 
   SegmentationResultID : String,
   BlockIdx : int
) : int;

public: int GetBlockLeft( 
   string* SegmentationResultID,
   int BlockIdx
)

public:
int GetBlockLeft( 
   String^ SegmentationResultID,
   int BlockIdx
)

Parameters

SegmentationResultID: The unique result identifier of the executed segmentation process obtained by the RRunSegmentation method.
BlockIdx: The 0-based index of the block within the specified segmentation result. It must be a value between 0 and GetBlockCount(SegmentationResultID)-1.

Return Value

The left x-coordinate of the block's bounding box, in pixels.

The GetStat method can be subsequently used to determine if this method has been successful.

Remarks

It is recommend to use the GetStat method to identify the specific reason for the method's failure, if any.

Please note, that the origin of the used coordinate system is in the top-left corner of the processed image and the used units are pixels.

Example

How to find out detected blocks within the segmentation result. All blocks are subsequently color-coded and saved into the output file.

VB.NET
C#

Dim caption As String = "Example: GetBlockLeft"
Using gdpictureSegmenter As GdPictureSegmenter = New GdPictureSegmenter()
    Using gdpictureImaging As GdPictureImaging = New GdPictureImaging()
        'Set up the image you want to process.
        Dim image As Integer = gdpictureImaging.CreateGdPictureImageFromFile("input.tif")
        If (gdpictureImaging.GetStat() = GdPictureStatus.OK) AndAlso
           (gdpictureSegmenter.SetImage(image) = GdPictureStatus.OK) Then
            'Set the segmentation mode.
            gdpictureSegmenter.SegmentationMode = SegmentationMode.ConnectedComponents4
            'Run the segmentation process.
            Dim resultID As String = gdpictureSegmenter.RunSegmentation()
            If gdpictureSegmenter.GetStat() = GdPictureStatus.OK Then
                'Check the results.
                Dim blockCount As Integer = gdpictureSegmenter.GetBlockCount(resultID)
                If gdpictureSegmenter.GetStat() = GdPictureStatus.OK Then
                    Dim message As String = "The number of detected blocks: "
                    message = message + blockCount.ToString() + vbCrLf
                    Dim top As Integer = 0, left As Integer = 0, bottom As Integer = 0, right As Integer = 0, save As Integer = 0
                    For i As Integer = 0 To blockCount - 1
                        top = gdpictureSegmenter.GetBlockTop(resultID, i)
                        If gdpictureSegmenter.GetStat() = GdPictureStatus.OK Then left = gdpictureSegmenter.GetBlockLeft(resultID, i)
                        If gdpictureSegmenter.GetStat() = GdPictureStatus.OK Then bottom = gdpictureSegmenter.GetBlockBottom(resultID, i)
                        If gdpictureSegmenter.GetStat() = GdPictureStatus.OK Then right = gdpictureSegmenter.GetBlockRight(resultID, i)
                        If gdpictureSegmenter.GetStat() = GdPictureStatus.OK Then
                            If gdpictureImaging.DrawRectangle(image, left, top, right - left, bottom - top, 5, Color.Brown, True) = GdPictureStatus.OK Then
                                message = message + (i + 1).ToString() + ".rectangle has been drawn." + vbCrLf
                                save += 1
                            Else
                                message = message + (i + 1).ToString() + ".rectangle HAS NOT been drawn. Status: " + gdpictureSegmenter.GetStat().ToString() + vbCrLf
                            End If
                        Else
                            message = message + i.ToString() + ".block has failed to get its position. Status: " + gdpictureSegmenter.GetStat().ToString() + vbCrLf
                        End If
                    Next
                    If blockCount = 0 Then
                        message = message + "The resulting image HAS NOT been created."
                    Else
                        If save = blockCount Then
                            If gdpictureImaging.SaveAsTIFF(image, "output.tif", TiffCompression.TiffCompressionAUTO) = GdPictureStatus.OK Then
                                message = message + "The resulting image HAS been saved successfully."
                            Else
                                message = message + "The resulting image HAS NOT been saved. Status: " + gdpictureImaging.GetStat().ToString()
                            End If
                        End If
                    End If
                    MessageBox.Show(message, caption)
                Else
                    MessageBox.Show("The GetBlockCount() method has failed with the status: " + gdpictureSegmenter.GetStat().ToString(), caption)
                End If
            Else
                MessageBox.Show("The segmentation process has failed with the status: " + gdpictureSegmenter.GetStat().ToString(), caption)
            End If
            'Release the used image.
            gdpictureImaging.ReleaseGdPictureImage(image)
        Else
            MessageBox.Show("The error occurred when setting up the image: " + gdpictureImaging.GetStat().ToString() + " or " + gdpictureSegmenter.GetStat().ToString(), caption)
        End If
    End Using
    'Release resources.
    gdpictureSegmenter.ReleaseSegmentationResults()
End Using

string caption = "Example: GetBlockLeft";
using (GdPictureSegmenter gdpictureSegmenter = new GdPictureSegmenter())
{
    using (GdPictureImaging gdpictureImaging = new GdPictureImaging())
    {
        //Set up the image you want to process.
        int image = gdpictureImaging.CreateGdPictureImageFromFile("input.tif");
        if ((gdpictureImaging.GetStat() == GdPictureStatus.OK) &&
            (gdpictureSegmenter.SetImage(image) == GdPictureStatus.OK))
        {
            //Set the segmentation mode.
            gdpictureSegmenter.SegmentationMode = SegmentationMode.ConnectedComponents4;
            //Run the segmentation process.
            string resultID = gdpictureSegmenter.RunSegmentation();
            if (gdpictureSegmenter.GetStat() == GdPictureStatus.OK)
            {
                //Check the results.
                int blockCount = gdpictureSegmenter.GetBlockCount(resultID);
                if (gdpictureSegmenter.GetStat() == GdPictureStatus.OK)
                {
                    string message = "The number of detected blocks: ";
                    message = message + blockCount.ToString() + "\n";                                
                    int top = 0, left = 0, bottom = 0, right = 0, save = 0;
                    for (int i = 0; i < blockCount; i++)
                    {
                        top = gdpictureSegmenter.GetBlockTop(resultID, i);
                        if (gdpictureSegmenter.GetStat() == GdPictureStatus.OK)
                            left = gdpictureSegmenter.GetBlockLeft(resultID, i);
                        if (gdpictureSegmenter.GetStat() == GdPictureStatus.OK)
                            bottom = gdpictureSegmenter.GetBlockBottom(resultID, i);
                        if (gdpictureSegmenter.GetStat() == GdPictureStatus.OK)
                            right = gdpictureSegmenter.GetBlockRight(resultID, i);
                        if (gdpictureSegmenter.GetStat() == GdPictureStatus.OK)
                        {
                            if (gdpictureImaging.DrawRectangle(image, left, top, right - left, bottom - top, 5, Color.Brown, true) == GdPictureStatus.OK)
                            {
                                message = message + (i + 1).ToString() + ".rectangle has been drawn.\n";
                                save++;
                            }
                            else
                                message = message + (i + 1).ToString() + ".rectangle HAS NOT been drawn. Status: " + gdpictureSegmenter.GetStat().ToString() + "\n";
                        }
                        else
                            message = message + i.ToString() + ".block has failed to get its position. Status: " + gdpictureSegmenter.GetStat().ToString() + "\n";
                    }
                    if (blockCount == 0)
                    {
                        message = message + "The resulting image HAS NOT been created.";
                    }
                    else
                    { 
                        if (save == blockCount)
                        {
                           if (gdpictureImaging.SaveAsTIFF(image, "output.tif", TiffCompression.TiffCompressionAUTO) == GdPictureStatus.OK)
                               message = message + "The resulting image HAS been saved successfully.";
                           else
                               message = message + "The resulting image HAS NOT been saved. Status: " + gdpictureImaging.GetStat().ToString();
                        }
                    }
                    MessageBox.Show(message, caption);
                }
                else
                {
                    MessageBox.Show("The GetBlockCount() method has failed with the status: " + gdpictureSegmenter.GetStat().ToString(), caption);
                }
            }
            else
            {
                MessageBox.Show("The segmentation process has failed with the status: " + gdpictureSegmenter.GetStat().ToString(), caption);
            }
            //Release the used image.
            gdpictureImaging.ReleaseGdPictureImage(image);
        }
        else
            MessageBox.Show("The error occurred when setting up the image: " + gdpictureImaging.GetStat().ToString() + " or " + gdpictureSegmenter.GetStat().ToString(), caption);
    }
    //Release resources.
    gdpictureSegmenter.ReleaseSegmentationResults();
}

Reference

GdPictureSegmenter Class
GdPictureSegmenter Members
GetBlockCount Method
GetBlockRight Method
GetBlockTop Method
GetBlockBottom Method
RunSegmentation Method