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Capability Category

• BitDepthReductionAttribute - Specifies the Reduction Method the Source should use to reduce the bit depth of the data

  [BitDepthReduction(TwBR.Threshold, TwBR.Diffusion)] //ICAP_BITDEPTHREDUCTION
  public sealed class ScreenDataSource:BitmapDataSource {
  

• CompressionAttribute - Define compression schemes for Buffered Memory and File transfers

  [Compression(TwCompression.Jpeg/**,TwCompression.Png, ... **/)] //ICAP_COMPRESSION
  public sealed class ScreenDataSource:BitmapDataSource {
  

• CustHalftoneAttribute - Specifies the square-cell halftone (dithering) matrix the Source should use to halftone the image.

  [CustHalftone(...)] //ICAP_CUSTHALFTONE
  public sealed class ScreenDataSource:BitmapDataSource {
  

• DevicePropertiesAttribute - Define device properties

  [DeviceProperties(
    16f, //ICAP_PHYSICALWIDTH
    9f, //ICAP_PHYSICALHEIGHT
    100f, //ICAP_XNATIVERESOLUTION
    100f)] //ICAP_YNATIVERESOLUTION
  public sealed class ScreenDataSource:BitmapDataSource {
  

• HalftonesAttribute - Define a list of names of the halftone patterns available within the Source

  [Halftones("A1","A2","A3")] //ICAP_HALFTONES
  public sealed class ScreenDataSource:BitmapDataSource {
  

• ImageFileFormatAttribute - Define which file formats the Source can generate

  [ImageFileFormat(TwFF.Bmp,TwFF.Tiff,TwFF.Jfif)] //ICAP_IMAGEFILEFORMAT
  public sealed class ScreenDataSource:BitmapDataSource {
  

• LsbFirstSupportedAttribute - Define that a Source supported LSB (ICAP_BITORDER)

  [LsbFirstSupported] //ICAP_BITORDER
  public sealed class ScreenDataSource:BitmapDataSource {
  

• PixelFlavorAttribute - Define sense of the pixel whose numeric value is zero (minimum data value)

  [PixelFlavor(TwPF.Chocolate)] //ICAP_PIXELFLAVOR
  public sealed class ScreenDataSource:BitmapDataSource {
  

• PixelTypeAttribute - Define the type of pixel data that a Source is capable of acquiring (for example, black and white, gray, RGB, etc.)

  [PixelType(TwPixelType.RGB,DefaultValue = TwPixelType.RGB)] //ICAP_PIXELTYPE
  public sealed class ScreenDataSource:BitmapDataSource {
  

• PlanarChunkyAttribute - Define color data formats are available

  [PlanarChunky(TwPC.Chunky,DefaultValue = TwPC.Chunky)] //ICAP_PLANARCHUNKY
  public sealed class ScreenDataSource:BitmapDataSource {
  

• ThresholdAttribute - Specifies the dividing line between black and white. This is the value the Source will use to threshold, if needed, when ICAP_PIXELTYPE = TWPT_BW

  [Threshold(128f)] //ICAP_THRESHOLD
  public sealed class ScreenDataSource:BitmapDataSource {
  

Instead of using the above attributes you can override DataSource.OnCapabilityValueNeeded method.

protected override void OnCapabilityValueNeeded(CapabilityEventArgs e) {
    // ...
    for(var _cap = e.Capability.CapabilityInfo.Capability; this._Handlers.ContainsKey(_cap);) {
        this._Handlers[_cap](e.Capability);
        break;
    }

    // CAP_DEVICEONLINE 
    switch(e.Capability.CapabilityInfo.Capability) {
        case TwCap.DeviceOnline:
            e.Capability.Value=this._Screen!=null;
            break;
    }
    // ...
}