' Opens JPEG2000 file and gets its first tile's image by parts.
Public Shared Function GetJpeg2000TileByParts(jpeg2000Filename As String) As Vintasoft.Imaging.VintasoftImage
    ' open an existing JPEG2000 file
    Using file As New Vintasoft.Imaging.Codecs.ImageFiles.Jpeg2000.Jpeg2000File(jpeg2000Filename, System.IO.FileMode.Open, System.IO.FileAccess.Read)
        ' get JPEG2000 page
        Dim page As Vintasoft.Imaging.Codecs.ImageFiles.Jpeg2000.Jpeg2000Page = file.Page

        ' get page dimensions and pixel format
        Dim imageWidth As Integer = page.Width
        Dim imageHeight As Integer = page.Height

        Dim palette As Vintasoft.Imaging.Palette = If(page.Palette IsNot Nothing, page.Palette, New Vintasoft.Imaging.Palette())
        Dim imageInfo As New Vintasoft.Imaging.Codecs.Decoders.ImageInfo(imageWidth, imageHeight, page.BitsPerPixel, palette, page.Resolution)
        Dim pixelFormat As Vintasoft.Imaging.PixelFormat = imageInfo.PixelFormat

        ' get first tile rectangle
        Dim firstTileRectangle As System.Drawing.Rectangle = page.GetTileGrid()(0)

        ' get tile dimensions
        Dim tileWidth As Integer = firstTileRectangle.Width
        Dim tileHeight As Integer = firstTileRectangle.Height

        ' if tile is too small, then get tile at once
        If tileWidth = 1 OrElse tileHeight = 1 Then
            Return page.GetTileRectImage(0, New System.Drawing.Rectangle(0, 0, tileWidth, tileHeight), Nothing)
        End If

        ' divide tile rectangle into 4 rectangles
        Dim grid As System.Drawing.Rectangle() = New System.Drawing.Rectangle(3) {}
        grid(0) = New System.Drawing.Rectangle(0, 0, tileWidth \ 2, tileHeight \ 2)
        grid(1) = New System.Drawing.Rectangle(tileWidth \ 2, 0, (tileWidth + 1) \ 2, tileHeight \ 2)
        grid(2) = New System.Drawing.Rectangle(0, tileHeight \ 2, tileWidth \ 2, (tileHeight + 1) \ 2)
        grid(3) = New System.Drawing.Rectangle(tileWidth \ 2, tileHeight \ 2, (tileWidth + 1) \ 2, (tileHeight + 1) \ 2)

        ' get number of wavelet levels
        Dim waveletLevel As Integer = page.WaveletLevels

        ' create a VintasoftImage object
        Dim resultImage As New Vintasoft.Imaging.VintasoftImage(tileWidth, tileHeight, pixelFormat)

        ' for each part of tile
        For i As Integer = 0 To 3
            ' get current rectangle
            Dim rectangle As System.Drawing.Rectangle = grid(i)

            ' get current rectangle location
            Dim position As System.Drawing.Point = rectangle.Location

            ' get image of current rectangle
            Using rectImage As Vintasoft.Imaging.VintasoftImage = page.GetTileRectImage(0, rectangle, waveletLevel, Nothing)
                ' overlay rectangle image on result image
                Dim overlayCommand As New Vintasoft.Imaging.ImageProcessing.OverlayCommand(rectImage, position)
                overlayCommand.ExecuteInPlace(resultImage)
            End Using
        Next

        Return resultImage
    End Using
End Function

// Opens JPEG2000 file and gets its first tile's image by parts.
public static Vintasoft.Imaging.VintasoftImage GetJpeg2000TileByParts(string jpeg2000Filename)
{
    // open an existing JPEG2000 file
    using (Vintasoft.Imaging.Codecs.ImageFiles.Jpeg2000.Jpeg2000File file =
        new Vintasoft.Imaging.Codecs.ImageFiles.Jpeg2000.Jpeg2000File(
            jpeg2000Filename, System.IO.FileMode.Open, System.IO.FileAccess.Read))
    {
        // get JPEG2000 page
        Vintasoft.Imaging.Codecs.ImageFiles.Jpeg2000.Jpeg2000Page page = file.Page;

        // get page dimensions and pixel format
        int imageWidth = page.Width;
        int imageHeight = page.Height;

        Vintasoft.Imaging.Palette palette = page.Palette != null ? page.Palette : new Vintasoft.Imaging.Palette();
        Vintasoft.Imaging.Codecs.Decoders.ImageInfo imageInfo =
            new Vintasoft.Imaging.Codecs.Decoders.ImageInfo(
                imageWidth,
                imageHeight,
                page.BitsPerPixel,
                palette,
                page.Resolution);
        Vintasoft.Imaging.PixelFormat pixelFormat = imageInfo.PixelFormat;

        // get first tile rectangle
        System.Drawing.Rectangle firstTileRectangle = page.GetTileGrid()[0];

        // get tile dimensions
        int tileWidth = firstTileRectangle.Width;
        int tileHeight = firstTileRectangle.Height;

        // if tile is too small, then get tile at once
        if (tileWidth == 1 || tileHeight == 1)
            return page.GetTileRectImage(0, new System.Drawing.Rectangle(0, 0, tileWidth, tileHeight), null);

        // divide tile rectangle into 4 rectangles
        System.Drawing.Rectangle[] grid = new System.Drawing.Rectangle[4];
        grid[0] = new System.Drawing.Rectangle(0, 0, tileWidth / 2, tileHeight / 2);
        grid[1] = new System.Drawing.Rectangle(tileWidth / 2, 0, (tileWidth + 1) / 2, tileHeight / 2);
        grid[2] = new System.Drawing.Rectangle(0, tileHeight / 2, tileWidth / 2, (tileHeight + 1) / 2);
        grid[3] = new System.Drawing.Rectangle(tileWidth / 2, tileHeight / 2, (tileWidth + 1) / 2, (tileHeight + 1) / 2);

        // get number of wavelet levels
        int waveletLevel = page.WaveletLevels;

        // create a VintasoftImage object
        Vintasoft.Imaging.VintasoftImage resultImage =
            new Vintasoft.Imaging.VintasoftImage(tileWidth, tileHeight, pixelFormat);

        // for each part of tile
        for (int i = 0; i < 4; i++)
        {
            // get current rectangle
            System.Drawing.Rectangle rectangle = grid[i];

            // get current rectangle location
            System.Drawing.Point position = rectangle.Location;

            // get image of current rectangle
            using (Vintasoft.Imaging.VintasoftImage rectImage = page.GetTileRectImage(0, rectangle, waveletLevel, null))
            {
                // overlay rectangle image on result image
                Vintasoft.Imaging.ImageProcessing.OverlayCommand overlayCommand =
                    new Vintasoft.Imaging.ImageProcessing.OverlayCommand(rectImage, position);
                overlayCommand.ExecuteInPlace(resultImage);
            }
        }

        return resultImage;
    }
}