RasterBufferResize Class

Provides support for resizing image data buffers.

Object Model

Syntax

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

public class RasterBufferResize

'Declaration

Public Class RasterBufferResize

'Usage

Dim instance As RasterBufferResize

public sealed class RasterBufferResize

function Leadtools.RasterBufferResize()

public ref class RasterBufferResize

Example

This example will load an image, resizes each line then saves the resized image back to disk.

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

Copy Code

Imports Leadtools
Imports Leadtools.Codecs

      
  Public Sub RasterBufferResizeExample()
   Dim codecs As RasterCodecs = New RasterCodecs()
   codecs.ThrowExceptionsOnInvalidImages = True
   Dim srcFileName As String = Path.Combine(LEAD_VARS.ImagesDir, "Image1.cmp")
   Dim destFileName As String = Path.Combine(LEAD_VARS.ImagesDir, "Image1_resized.bmp")

   ' Load the source image
   Dim srcImage As RasterImage = codecs.Load(srcFileName)

   Dim destWidth As Integer = srcImage.Width \ 2
   Dim destHeight As Integer = srcImage.Height \ 2

   ' Create the destination image
   Dim destImage As RasterImage = New RasterImage( _
                                  RasterMemoryFlags.Conventional, _
                                  destWidth, destHeight, srcImage.BitsPerPixel, srcImage.Order, _
                                  srcImage.ViewPerspective, srcImage.GetPalette(), IntPtr.Zero, 0)

   ' allocate buffer for one scanline from source image
   Dim scanLine As Byte() = New Byte(srcImage.BytesPerLine - 1) {}

   ' resize it
   Dim bufferResize As RasterBufferResize = New RasterBufferResize()

   ' Initialize the resize process.
   bufferResize.Start(srcImage.Width, srcImage.Height, destImage.Width, destImage.Height)

   srcImage.Access()
   destImage.Access()

   ' Current destination row number
   Dim destRow As Integer = 0
   Dim i As Integer = 0
   Do While i < srcImage.Height
      ' Get a scanline from the source image and resize it
      srcImage.GetRow(i, scanLine, 0, srcImage.BytesPerLine)
      bufferResize.ResizeBuffer(scanLine, 0, i, srcImage.BitsPerPixel)

      ' Output as many or as few rows as ResizeBuffer supplies
      Dim j As Integer = 0
      Do While j < bufferResize.CopyRepetitions
         destImage.SetRow(destRow, scanLine, 0, bufferResize.LineWidth * 3)
         destRow += 1
         j += 1
      Loop
      i += 1
   Loop

   destImage.Release()
   srcImage.Release()

   bufferResize.Stop()

   ' Save the destination image
   codecs.Save(destImage, destFileName, RasterImageFormat.Bmp, 24)

   ' Clean up
   srcImage.Dispose()
   destImage.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;

      
public void RasterBufferResizeExample()
{
   string srcFileName = Path.Combine(ImagesPath.Path, "Image1.cmp");
   string destFileName = Path.Combine(ImagesPath.Path, "Image1_resized.bmp");
   using (RasterCodecs codecs = new RasterCodecs())
   {
      codecs.ThrowExceptionsOnInvalidImages = true;

      // Load the source image
      using (RasterImage srcImage = codecs.Load(srcFileName))
      {
         int destWidth = srcImage.Width / 2;
         int destHeight = srcImage.Height / 2;

         // Create the destination image
         using (RasterImage destImage = new RasterImage(
            RasterMemoryFlags.Conventional,
            destWidth,
            destHeight,
            srcImage.BitsPerPixel,
            srcImage.Order,
            srcImage.ViewPerspective,
            srcImage.GetPalette(),
            IntPtr.Zero,
            0))
         {

            // allocate buffer for one scanline from source image
            byte[] scanLine = new byte[srcImage.BytesPerLine];

            // resize it
            RasterBufferResize bufferResize = new RasterBufferResize();

            // Initialize the resize process.
            bufferResize.Start(srcImage.Width, srcImage.Height, destImage.Width, destImage.Height);

            srcImage.Access();
            destImage.Access();

            // Current destination row number
            int destRow = 0;
            for (int i = 0; i < srcImage.Height; i++)
            {
               // Get a scanline from the source image and resize it
               srcImage.GetRow(i, scanLine, 0, srcImage.BytesPerLine);
               bufferResize.ResizeBuffer(scanLine, 0, i, srcImage.BitsPerPixel);

               // Output as many or as few rows as ResizeBuffer supplies
               for (int j = 0; j < bufferResize.CopyRepetitions; j++)
               {
                  destImage.SetRow(destRow, scanLine, 0, bufferResize.LineWidth * 3);
                  destRow++;
               }
            }

            destImage.Release();
            srcImage.Release();

            bufferResize.Stop();

            // Save the destination image
            codecs.Save(destImage, destFileName, RasterImageFormat.Bmp, 24);
         }
      }
   }
}

using Leadtools;
using Leadtools.Codecs;

      
public async Task RasterBufferResizeExample()
{
   RasterCodecs codecs = new RasterCodecs();
   codecs.ThrowExceptionsOnInvalidImages = true;
   string srcFileName = @"Assets\Image1.cmp";
   string destFileName = @"Image1_resized.bmp";

   // Load the source image
   StorageFile loadFile = await Tools.AppInstallFolder.GetFileAsync(srcFileName);
   ILeadStream loadStream = LeadStreamFactory.Create(loadFile);
   RasterImage srcImage = await codecs.LoadAsync(loadStream, 24, CodecsLoadByteOrder.Bgr, 1, 1);
   Assert.IsTrue(srcImage.BitsPerPixel == 24);

   int destWidth = srcImage.Width / 2;
   int destHeight = srcImage.Height / 2;

   // Create the destination image
   RasterImage destImage = new RasterImage(
      RasterMemoryFlags.Conventional,
      destWidth,
      destHeight,
      srcImage.BitsPerPixel,
      srcImage.Order,
      srcImage.ViewPerspective,
      srcImage.GetPalette());

   // allocate buffer for one scanline from source image
   Windows.Storage.Streams.Buffer scanLine = new Windows.Storage.Streams.Buffer((uint)srcImage.BytesPerLine);

   // resize it
   RasterBufferResize bufferResize = new RasterBufferResize();

   // Initialize the resize process.
   bufferResize.Start(srcImage.Width, srcImage.Height, destImage.Width, destImage.Height);

   srcImage.AccessData();
   destImage.AccessData();

   // Current destination row number
   int destRow = 0;
   for(int i = 0; i < srcImage.Height; i++)
   {
      // Get a scanline from the source image and resize it
      srcImage.GetRow(i, scanLine, 0, srcImage.BytesPerLine);
      bufferResize.ResizeBuffer(scanLine, 0, i, srcImage.BitsPerPixel);

      // Output as many or as few rows as ResizeBuffer supplies
      for(int j = 0; j < bufferResize.CopyRepetitions; j++)
      {
         destImage.SetRow(destRow, scanLine, 0, bufferResize.LineWidth * 3);
         destRow++;
      }
   }

   destImage.ReleaseData();
   srcImage.ReleaseData();

   bufferResize.Stop();

   // Save the destination image
   StorageFile saveFile = await Tools.AppLocalFolder.CreateFileAsync(destFileName);
   ILeadStream saveStream = LeadStreamFactory.Create(saveFile);
   await codecs.SaveAsync(destImage, saveStream, RasterImageFormat.Bmp, 24);

   // Clean up
   srcImage.Dispose();
   destImage.Dispose();
}

using Leadtools;
using Leadtools.Codecs;
using Leadtools.Examples;

public void RasterBufferResizeExample(RasterImage srcImage, Stream destStream)
{
   RasterCodecs codecs = new RasterCodecs();
   codecs.ThrowExceptionsOnInvalidImages = true;
   int destWidth = srcImage.Width / 2;
   int destHeight = srcImage.Height / 2;

   // Create the destination image
   RasterImage destImage = new RasterImage(
      RasterMemoryFlags.Conventional,
      destWidth,
      destHeight,
      srcImage.BitsPerPixel,
      srcImage.Order,
      srcImage.ViewPerspective,
      srcImage.GetPalette(),
      null,
      0);

   // allocate buffer for one scanline from source image
   byte[] scanLine = new byte[srcImage.BytesPerLine];

   // resize it
   RasterBufferResize bufferResize = new RasterBufferResize();

   // Initialize the resize process.
   bufferResize.Start(srcImage.Width, srcImage.Height, destImage.Width, destImage.Height);

   srcImage.Access();
   destImage.Access();

   // Current destination row number
   int destRow = 0;
   for(int i = 0; i < srcImage.Height; i++)
   {
      // Get a scanline from the source image and resize it
      srcImage.GetRow(i, scanLine, 0, srcImage.BytesPerLine);
      bufferResize.ResizeBuffer(scanLine, 0, i, srcImage.BitsPerPixel);

      // Output as many or as few rows as ResizeBuffer supplies
      for(int j = 0; j < bufferResize.CopyRepetitions; j++)
      {
         destImage.SetRow(destRow, scanLine, 0, bufferResize.LineWidth * 3);
         destRow++;
      }
   }

   destImage.Release();
   srcImage.Release();

   bufferResize.Stop();

   // Save the destination image
   codecs.Save(destImage, destStream, RasterImageFormat.Bmp, 24);

   // Clean up
   srcImage.Dispose();
   destImage.Dispose();
}

Imports Leadtools
Imports Leadtools.Codecs

Public Sub RasterBufferResizeExample(ByVal srcImage As RasterImage, ByVal destStream As Stream)
   Dim codecs As RasterCodecs = New RasterCodecs()
   codecs.ThrowExceptionsOnInvalidImages = True
   Dim destWidth As Integer = srcImage.Width / 2
   Dim destHeight As Integer = srcImage.Height / 2

   ' Create the destination image
   Dim destImage As RasterImage = New RasterImage(RasterMemoryFlags.Conventional, destWidth, destHeight, srcImage.BitsPerPixel, srcImage.Order, srcImage.ViewPerspective, srcImage.GetPalette(), Nothing, 0)

   ' allocate buffer for one scanline from source image
   Dim scanLine As Byte() = New Byte(srcImage.BytesPerLine - 1){}

   ' resize it
   Dim bufferResize As RasterBufferResize = New RasterBufferResize()

   ' Initialize the resize process.
   bufferResize.Start(srcImage.Width, srcImage.Height, destImage.Width, destImage.Height)

   srcImage.Access()
   destImage.Access()

   ' Current destination row number
   Dim destRow As Integer = 0
   Dim i As Integer = 0
   Do While i < srcImage.Height
      ' Get a scanline from the source image and resize it
      srcImage.GetRow(i, scanLine, 0, srcImage.BytesPerLine)
      bufferResize.ResizeBuffer(scanLine, 0, i, srcImage.BitsPerPixel)

      ' Output as many or as few rows as ResizeBuffer supplies
      Dim j As Integer = 0
      Do While j < bufferResize.CopyRepetitions
         destImage.SetRow(destRow, scanLine, 0, bufferResize.LineWidth * 3)
         destRow += 1
         j += 1
      Loop
      i += 1
   Loop

   destImage.Release()
   srcImage.Release()

   bufferResize.Stop()

   ' Save the destination image
   codecs.Save(destImage, destStream, RasterImageFormat.Bmp, 24)

   ' Clean up
   srcImage.Dispose()
   destImage.Dispose()
End Sub

Requirements

Target Platforms

Reference

RasterBufferResize Members
Leadtools Namespace