VintaSoft Imaging .NET SDK 14.0: Documentation for .NET developer
Vintasoft.Imaging.Codecs.Decoders Namespace / JpegDecoder Class / GetThumbnail Methods / GetThumbnail(Int32,Size,DecodingSettings,RenderingSettings,Boolean,EventHandler<ProgressEventArgs>) Method
Syntax Remarks Requirements SeeAlso
In This Topic
    GetThumbnail(Int32,Size,DecodingSettings,RenderingSettings,Boolean,EventHandler<ProgressEventArgs>) Method (JpegDecoder)
    In This Topic
    Returns a thumbnail image of the specified page of the image source.
    Syntax
    'Declaration
    
    Public Overloads Overrides Function GetThumbnail( _
    ByVal pageIndex
    The zero based page index. This parameter is not used and can be set to 0.
    As System.Int32, _
    ByVal decodingSettings
    Decoding settings, which must be used for decoding the thumbnail of page.
    As System.Drawing.Size, _
    ByVal renderingSettings
    Rendering settings, which must be used for rendering the thumbnail of page.
    As DecodingSettings, _
    ByVal size
    Size of the thumbnail.
    As RenderingSettings, _
    ByVal useImageRendering
    A value indicating whether the decoder can use ImageRenderer for rendering thumbnail image.
    As Boolean, _
    ByVal thumbnailLoadingProgress
    Delegate of the thumbnail loading progress. Can be set to null (Nothing in Visual Basic).
    As System.EventHandler(Of ProgressEventArgs) _
    ) As Vintasoft.Imaging.VintasoftImage

    Parameters

    pageIndex
    The zero based page index. This parameter is not used and can be set to 0.
    decodingSettings
    Decoding settings, which must be used for decoding the thumbnail of page.
    renderingSettings
    Rendering settings, which must be used for rendering the thumbnail of page.
    size
    Size of the thumbnail.
    useImageRendering
    A value indicating whether the decoder can use ImageRenderer for rendering thumbnail image.
    thumbnailLoadingProgress
    Delegate of the thumbnail loading progress. Can be set to null (Nothing in Visual Basic).

    Return Value

    Thumbnail image of the specified page of the image source.
    Remarks

    Method does the following steps:

    • Tries to get thumbnail from JFIF-segment.
    • Tries to get thumbnail from JFXX-segment if thumbnail is not found on the previous step.
    • Tries to get thumbnail from EXIF-segment if thumbnail is not found on the previous steps.
    • Generates image thumbnail if thumbnail is not found on the previous steps OR image and thumbnail are not proportional.

    Requirements

    Target Platforms: .NET9; .NET 8; .NET 7; .NET 6; .NET Framework 4.8, 4.7, 4.6, 4.5, 4.0, 3.5

    See Also