GetRowCompressed(Byte[],UInt16[],Int32,Int32,Int32) Method

C#
Visual Basic
WinRT C#
Java
Objective-C
WinRT JavaScript
C++

[CLSCompliantAttribute(false)]
public void GetRowCompressed( 
   byte[] workBuffer,
   ushort[] runBuffer,
   int runBufferOffset,
   int row,
   int lines
)

'Declaration

<CLSCompliantAttribute(False)>
Public Overloads Sub GetRowCompressed( _
   ByVal workBuffer() As Byte, _
   ByVal runBuffer() As UShort, _
   ByVal runBufferOffset As Integer, _
   ByVal row As Integer, _
   ByVal lines As Integer _
)

'Usage

Dim instance As RasterImage
Dim workBuffer() As Byte
Dim runBuffer() As UShort
Dim runBufferOffset As Integer
Dim row As Integer
Dim lines As Integer
 
instance.GetRowCompressed(workBuffer, runBuffer, runBufferOffset, row, lines)

[CLSCompliantAttribute(false)]
public void GetRowCompressed( 
   byte[] workBuffer,
   ushort[] runBuffer,
   int runBufferOffset,
   int row,
   int lines
)

- (BOOL)getRowCompressed:(unsigned char *)workBuffer 
               runBuffer:(unsigned short *)runBuffer 
                     row:(NSUInteger)row 
                   lines:(NSUInteger)lines 
                   error:(NSError **)error

public void getRowCompressed(
  byte[] workBuffer, 
  short[] runBuffer, 
  int runBufferOffset, 
  int row, 
  int lines
)

CLSCompliantAttribute()
 function Leadtools.RasterImage.GetRowCompressed(Byte[],UInt16[],Int32,Int32,Int32)( 
   workBuffer ,
   runBuffer ,
   runBufferOffset ,
   row ,
   lines 
)

[CLSCompliantAttribute(false)]
public:
void GetRowCompressed( 
   array<byte>^ workBuffer,
   array<ushort>^ runBuffer,
   int runBufferOffset,
   int row,
   int lines
)

Parameters

workBuffer: Optional work buffer. Allocating the work buffer speeds processing if you call this method more than once, because if you do not allocate a work buffer, the method allocates and frees a temporary buffer each time it is called. bytes required = lines * ((Width + 3) * 2). Pass a null reference to runBuffer if you do not want to use a work buffer.
runBuffer: The output buffer, which will be filled with 1-bit compressed image data.
runBufferOffset: Offset into runBuffer where the copy operation should start.
row: The number of the row to retrieve. The first row is 0, and the last row is 1 less than the image height.
lines: Number of rows to retrieve.

This method is available in the (Document/Medical only) Toolkits.

This method is useful for working with 1-bit images that are loaded in their compressed formats for faster loading and display.

For more information, refer to Speeding Up 1-Bit Documents.

This example demonstrates the low-level methods for accessing 1-bit compressed image data. It demonstrates the ability to get and put rows, and the ability to process rows in buffer-to-buffer processing. The result of the function is an the first 50 lines are inverted.

C#
Visual Basic
WinRT C#
WinRT JavaScript
Silverlight C#
Silverlight VB

Copy Code

Imports Leadtools
Imports Leadtools.Codecs
Imports Leadtools.ImageProcessing
Imports Leadtools.ImageProcessing.Core
Imports Leadtools.ImageProcessing.Color
Imports Leadtools.Controls
Imports Leadtools.Dicom
Imports Leadtools.Drawing
Imports Leadtools.Svg

      
Public Sub GetRowCompressedExample()
   Dim codecs As RasterCodecs = New RasterCodecs()
   ' Load the bitmap, at 1 bit per pixel, compressed
   codecs.Options.Load.Compressed = True
   Dim image As RasterImage = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "OCR1.TIF"), 1, CodecsLoadByteOrder.Bgr, 1, 1)
   ' This example does not work with rotated view perspectives.
   If (image.ViewPerspective <> RasterViewPerspective.TopLeft) OrElse (image.ViewPerspective <> RasterViewPerspective.BottomLeft) Then
      image.ChangeViewPerspective(RasterViewPerspective.TopLeft)
   End If

   ' Adjust the YOffset if the view perspective is bottom left.
   Dim nRow As Integer = 500 ' first row to get.
   Dim nYSize As Integer = 500 ' number of rows to get.

   If image.ViewPerspective = RasterViewPerspective.BottomLeft Then
      nRow = image.Height - nRow - nYSize
   End If

   ' Allocate the buffers.
   Dim pBuffer As Byte() = New Byte(Convert.ToInt32((((image.Width + 31) And Not (31)) / 8)) * nYSize - 1) {} ' Buffer to hold the expanded row.
   Dim pRunBuffer As System.UInt16() = New System.UInt16(((image.Width + 3) * 2) * nYSize - 1) {} ' Buffer to hold the compressed row.

   If image.IsGlobalMemory Then
      image.Access()
   End If
   ' Get the top nRow lines.
   image.GetRowCompressed(Nothing, pRunBuffer, 0, nRow, nYSize)
   ' Expand the compressed data.
   RasterRleCompressor.ExpandRows(pRunBuffer, pBuffer, 0, image.Width, nYSize)
   ' Invert the data.

   Dim n As Integer = 0
   Do While n < (image.BytesPerLine * nYSize)
      pBuffer(n) = pBuffer(n) Xor Convert.ToByte(&HFF)
      n += 1
   Loop


   ' Compress the inverted data.
   RasterRleCompressor.CompressRows(pRunBuffer, pBuffer, 0, image.Width, nYSize)

   ' Put the inverted, compressed data back into the image.
   image.SetRowCompressed(Nothing, pRunBuffer, 0, nRow, nYSize)

   If image.IsGlobalMemory Then
      image.Release()
   End If

   codecs.Save(image, Path.Combine(LEAD_VARS.ImagesDir, "IMAGE1_getrowcompresed.BMP"), RasterImageFormat.Bmp, 0)

   image.Dispose()
   codecs.Dispose()
End Sub

Public NotInheritable Class LEAD_VARS
Public Const ImagesDir As String = "C:\Users\Public\Documents\LEADTOOLS Images"
End Class

using Leadtools;
using Leadtools.Codecs;
using Leadtools.ImageProcessing;
using Leadtools.ImageProcessing.Core;
using Leadtools.ImageProcessing.Color;
using Leadtools.Dicom;
using Leadtools.Drawing;
using Leadtools.Controls;
using Leadtools.Svg;

      
public void GetRowCompressedExample()
{
   RasterCodecs codecs = new RasterCodecs();
   // Load the bitmap, at 1 bit per pixel, compressed
   codecs.Options.Load.Compressed = true;
   RasterImage image = codecs.Load(Path.Combine(ImagesPath.Path, "OCR1.TIF"), 1, Leadtools.Codecs.CodecsLoadByteOrder.Bgr, 1, 1);
   // This example does not work with rotated view perspectives.
   if((image.ViewPerspective != RasterViewPerspective.TopLeft) || (image.ViewPerspective != RasterViewPerspective.BottomLeft))
      image.ChangeViewPerspective(RasterViewPerspective.TopLeft);

   // Adjust the YOffset if the view perspective is bottom left.
   int nRow = 500; // first row to get.
   int nYSize = 500; // number of rows to get.

   if(image.ViewPerspective == RasterViewPerspective.BottomLeft)
      nRow = image.Height - nRow - nYSize;

   // Allocate the buffers.
   byte[] pBuffer = new byte[Convert.ToInt32((((image.Width + 31) & ~(31)) / 8)) * nYSize]; // Buffer to hold the expanded row.
   ushort[] pRunBuffer = new ushort[((image.Width + 3) * 2) * nYSize]; // Buffer to hold the compressed row.

   if(image.IsGlobalMemory)
      image.Access();
   // Get the top nRow lines.
   image.GetRowCompressed(null, pRunBuffer, 0, nRow, nYSize);
   // Expand the compressed data.
   RasterRleCompressor.ExpandRows(pRunBuffer, pBuffer, 0, image.Width, nYSize);
   // Invert the data.

   for(int n = 0; n < (image.BytesPerLine * nYSize); n++)
      pBuffer[n] ^= 0xff;


   // Compress the inverted data.
   RasterRleCompressor.CompressRows(pRunBuffer, pBuffer, 0, image.Width, nYSize);

   // Put the inverted, compressed data back into the image.
   image.SetRowCompressed(null, pRunBuffer, 0, nRow, nYSize);

   if(image.IsGlobalMemory)
      image.Release();

   codecs.Save(image,Path.Combine(ImagesPath.Path,"IMAGE1_getrowcompresed.BMP"), RasterImageFormat.Bmp, 0);

   image.Dispose();
   codecs.Dispose();
}

Target Platforms

Reference

RasterImage Class
RasterImage Members
Overload List