GdPicture14 Namespace / PdfImageMaskType Enumeration

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PdfImageMaskType Enumeration
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Specifies the type of the image masking.
Public Enum PdfImageMaskType 
   Inherits System.Enum
public enum PdfImageMaskType : System.Enum 
public enum PdfImageMaskType = class(System.Enum)
public enum PdfImageMaskType extends System.Enum
__value public enum PdfImageMaskType : public System.Enum 
public enum class PdfImageMaskType : public System.Enum 
PdfMaskTypeColorKey4In PDF 1.3, the Mask entry in an image dictionary may alternatively be an array specifying a range of colors to be masked out. Samples in the image, that fall within this range, are not painted, allowing the existing background to show through. The effect is similar to that of the video technique known as chroma-key.
PdfMaskTypeExplicit2In PDF 1.3, the Mask entry in an image dictionary may be an image mask, as described above under “Stencil Masking”, which serves as an explicit mask for the primary (base) image. The base image and the image mask need not have the same resolution (Width and Height values), but since all images are defined on the unit square in user space, their boundaries on the page will coincide, that is, they will overlay each other. The image mask indicates which places on the page are to be painted and which are to be masked out (left unchanged). Unmasked areas are painted with the corresponding portions of the base image, masked areas are not.
PdfMaskTypeNone0Standard bitmap without masking operation.
PdfMaskTypeSoft3Defines the Alpha channel to be applied to another image.
PdfMaskTypeStencil1A monochrome image, in which each sample is specified by a single bit. However, instead of being painted in opaque black and white, the image mask is treated as a stencil mask, that is partly opaque and partly transparent. Sample values in the image do not represent black and white pixels, rather, they designate places on the page that should either be marked with the current color or masked out (not marked at all). Areas, which are masked out, retain their former content. The effect is like applying paint in the current color through a cut-out stencil, which lets the paint reach the page in some places and masks it out in others.
PdfMaskTypeUnknown-1Unknown mask mode.
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