2.2.2.2 EmfPlusBitmap Object

The EmfPlusBitmap object specifies a bitmap that contains a graphics image.

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Width
Height
Stride
PixelFormat
Type
BitmapData (variable)
...

Width (4 bytes): A signed integer that specifies the width in pixels of the area occupied by the bitmap.

If the image is compressed, according to the Type field, this value is undefined and MUST be ignored.

Height (4 bytes): A signed integer that specifies the height in pixels of the area occupied by the bitmap.

If the image is compressed, according to the Type field, this value is undefined and MUST be ignored.

Stride (4 bytes): A signed integer that specifies the byte offset between the beginning of one scan-line and the next. This value is the number of bytes per pixel, which is specified in the PixelFormat field, multiplied by the width in pixels, which is specified in the Width field. The value of this field MUST be a multiple of four.

If the image is compressed, according to the Type field, this value is undefined and MUST be ignored.

PixelFormat (4 bytes): An unsigned integer that specifies the format of the pixels that make up the bitmap image. The supported pixel formats are specified in the PixelFormat enumeration (section 2.1.1.24).

If the image is compressed, according to the Type field, this value is undefined and MUST be ignored.

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X	X	X	X	X	X	X	X	X	X	N	E	P	A	G	I	BitsPerPixel								Index

X (1 bit): Reserved and MUST be ignored.

N (1 bit): If set, the pixel format is "canonical", which means that 32 bits per pixel are supported, with 24 bits for color components and an 8-bit alpha channel.

If clear, the pixel format is not canonical.

E (1 bit): If set, the pixel format supports extended colors in 16 bits per channel.

If clear, extended colors are not supported.

P (1 bit): If set, each color component in the pixel has been premultiplied by the pixel's alpha transparency value.

If clear, each color component is multiplied by the pixel's alpha transparency value when the source pixel is blended with the destination pixel.

A (1 bit): If set, the pixel format includes an alpha transparency component.

If clear, the pixel format does not include a component that specifies transparency.

G (1 bit): If set, the pixel format is supported in Windows GDI.

If clear, the pixel format is not supported in Windows GDI.

I (1 bit): If set, the pixel values are indexes into a palette.

If clear, the pixel values are actual colors.

BitsPerPixel (1 byte): The total number of bits per pixel.

Index (1 byte): The pixel format enumeration index.

Type (4 bytes): An unsigned integer that specifies the type of data in the BitmapData field. This value is defined in the BitmapDataType enumeration (section 2.1.1.2).

BitmapData (variable): Variable-length data that defines the bitmap data object specified in the Type field. The content and format of the data can be different for every bitmap type.

Graphics images are specified by EmfPlusImage objects (section 2.2.1.4). An EmfPlusBitmap object MUST be present in the ImageData field of an EmfPlusImage object if ImageTypeBitmap is specified in its Type field.

This object is generic and is used to specify different types of bitmap data, including:

• An EmfPlusBitmapData object (section 2.2.2.3); and

• An EmfPlusCompressedImage object (section 2.2.2.10).

See section 2.2.2 for the specification of additional structure objects.