BITMAPV5HEADER structure (wingdi.h)

The BITMAPV5HEADER structure is the bitmap information header file. It is an extended version of the BITMAPINFOHEADER structure.

Syntax

typedef struct {
  DWORD        bV5Size;
  LONG         bV5Width;
  LONG         bV5Height;
  WORD         bV5Planes;
  WORD         bV5BitCount;
  DWORD        bV5Compression;
  DWORD        bV5SizeImage;
  LONG         bV5XPelsPerMeter;
  LONG         bV5YPelsPerMeter;
  DWORD        bV5ClrUsed;
  DWORD        bV5ClrImportant;
  DWORD        bV5RedMask;
  DWORD        bV5GreenMask;
  DWORD        bV5BlueMask;
  DWORD        bV5AlphaMask;
  DWORD        bV5CSType;
  CIEXYZTRIPLE bV5Endpoints;
  DWORD        bV5GammaRed;
  DWORD        bV5GammaGreen;
  DWORD        bV5GammaBlue;
  DWORD        bV5Intent;
  DWORD        bV5ProfileData;
  DWORD        bV5ProfileSize;
  DWORD        bV5Reserved;
} BITMAPV5HEADER, *LPBITMAPV5HEADER, *PBITMAPV5HEADER;

Members

bV5Size

The number of bytes required by the structure. Applications should use this member to determine which bitmap information header structure is being used.

bV5Width

The width of the bitmap, in pixels.

If bV5Compression is BI_JPEG or BI_PNG, the bV5Width member specifies the width of the decompressed JPEG or PNG image in pixels.

bV5Height

The height of the bitmap, in pixels. If the value of bV5Height is positive, the bitmap is a bottom-up DIB and its origin is the lower-left corner. If bV5Height value is negative, the bitmap is a top-down DIB and its origin is the upper-left corner.

If bV5Height is negative, indicating a top-down DIB, bV5Compression must be either BI_RGB or BI_BITFIELDS. Top-down DIBs cannot be compressed.

If bV5Compression is BI_JPEG or BI_PNG, the bV5Height member specifies the height of the decompressed JPEG or PNG image in pixels.

bV5Planes

The number of planes for the target device. This value must be set to 1.

bV5BitCount

The number of bits that define each pixel and the maximum number of colors in the bitmap.

This member can be one of the following values.

Value Meaning
0 The number of bits per pixel is specified or is implied by the JPEG or PNG file format.
1 The bitmap is monochrome, and the bmiColors member of BITMAPINFO contains two entries. Each bit in the bitmap array represents a pixel. If the bit is clear, the pixel is displayed with the color of the first entry in the bmiColors color table. If the bit is set, the pixel has the color of the second entry in the table.
4 The bitmap has a maximum of 16 colors, and the bmiColors member of BITMAPINFO contains up to 16 entries. Each pixel in the bitmap is represented by a 4-bit index into the color table. For example, if the first byte in the bitmap is 0x1F, the byte represents two pixels. The first pixel contains the color in the second table entry, and the second pixel contains the color in the sixteenth table entry.
8 The bitmap has a maximum of 256 colors, and the bmiColors member of BITMAPINFO contains up to 256 entries. In this case, each byte in the array represents a single pixel.
16 The bitmap has a maximum of 2^16 colors. If the bV5Compression member of the BITMAPV5HEADER structure is BI_RGB, the bmiColors member of BITMAPINFO is NULL. Each WORD in the bitmap array represents a single pixel. The relative intensities of red, green, and blue are represented with five bits for each color component. The value for blue is in the least significant five bits, followed by five bits each for green and red. The most significant bit is not used. The bmiColors color table is used for optimizing colors used on palette-based devices, and must contain the number of entries specified by the bV5ClrUsed member of the BITMAPV5HEADER.If the bV5Compression member of the BITMAPV5HEADER is BI_BITFIELDS, the bmiColors member contains three DWORD color masks that specify the red, green, and blue components, respectively, of each pixel. Each WORD in the bitmap array represents a single pixel.

When the bV5Compression member is BI_BITFIELDS, bits set in each DWORD mask must be contiguous and should not overlap the bits of another mask. All the bits in the pixel do not need to be used.

24 The bitmap has a maximum of 2^24 colors, and the bmiColors member of BITMAPINFO is NULL. Each 3-byte triplet in the bitmap array represents the relative intensities of blue, green, and red, respectively, for a pixel. The bmiColors color table is used for optimizing colors used on palette-based devices, and must contain the number of entries specified by the bV5ClrUsed member of the BITMAPV5HEADER structure.
32 The bitmap has a maximum of 2^32 colors. If the bV5Compression member of the BITMAPV5HEADER is BI_RGB, the bmiColors member of BITMAPINFO is NULL. Each DWORD in the bitmap array represents the relative intensities of blue, green, and red for a pixel. The value for blue is in the least significant 8 bits, followed by 8 bits each for green and red. The high byte in each DWORD is not used. The bmiColors color table is used for optimizing colors used on palette-based devices, and must contain the number of entries specified by the bV5ClrUsed member of the BITMAPV5HEADER.If the bV5Compression member of the BITMAPV5HEADER is BI_BITFIELDS, the bmiColors member contains three DWORD color masks that specify the red, green, and blue components of each pixel. Each DWORD in the bitmap array represents a single pixel.

bV5Compression

Specifies that the bitmap is not compressed. The bV5RedMask, bV5GreenMask, and bV5BlueMask members specify the red, green, and blue components of each pixel. This is valid when used with 16- and 32-bpp bitmaps. This member can be one of the following values.

Value Meaning
BI_RGB An uncompressed format.
BI_RLE8 A run-length encoded (RLE) format for bitmaps with 8 bpp. The compression format is a two-byte format consisting of a count byte followed by a byte containing a color index. If bV5Compression is BI_RGB and the bV5BitCount member is 16, 24, or 32, the bitmap array specifies the actual intensities of blue, green, and red rather than using color table indexes. For more information, see Bitmap Compression.
BI_RLE4 An RLE format for bitmaps with 4 bpp. The compression format is a two-byte format consisting of a count byte followed by two word-length color indexes. For more information, see Bitmap Compression.
BI_BITFIELDS Specifies that the bitmap is not compressed and that the color masks for the red, green, and blue components of each pixel are specified in the bV5RedMask, bV5GreenMask, and bV5BlueMask members. This is valid when used with 16- and 32-bpp bitmaps.
BI_JPEG Specifies that the image is compressed using the JPEG file Interchange Format. JPEG compression trades off compression against loss; it can achieve a compression ratio of 20:1 with little noticeable loss.
BI_PNG Specifies that the image is compressed using the PNG file Interchange Format.

bV5SizeImage

The size, in bytes, of the image. This may be set to zero for BI_RGB bitmaps.

If bV5Compression is BI_JPEG or BI_PNG, bV5SizeImage is the size of the JPEG or PNG image buffer.

bV5XPelsPerMeter

The horizontal resolution, in pixels-per-meter, of the target device for the bitmap. An application can use this value to select a bitmap from a resource group that best matches the characteristics of the current device.

bV5YPelsPerMeter

The vertical resolution, in pixels-per-meter, of the target device for the bitmap.

bV5ClrUsed

The number of color indexes in the color table that are actually used by the bitmap. If this value is zero, the bitmap uses the maximum number of colors corresponding to the value of the bV5BitCount member for the compression mode specified by bV5Compression.

If bV5ClrUsed is nonzero and bV5BitCount is less than 16, the bV5ClrUsed member specifies the actual number of colors the graphics engine or device driver accesses. If bV5BitCount is 16 or greater, the bV5ClrUsed member specifies the size of the color table used to optimize performance of the system color palettes. If bV5BitCount equals 16 or 32, the optimal color palette starts immediately following the BITMAPV5HEADER. If bV5ClrUsed is nonzero, the color table is used on palettized devices, and bV5ClrUsed specifies the number of entries.

bV5ClrImportant

The number of color indexes that are required for displaying the bitmap. If this value is zero, all colors are required.

bV5RedMask

Color mask that specifies the red component of each pixel, valid only if bV5Compression is set to BI_BITFIELDS.

bV5GreenMask

Color mask that specifies the green component of each pixel, valid only if bV5Compression is set to BI_BITFIELDS.

bV5BlueMask

Color mask that specifies the blue component of each pixel, valid only if bV5Compression is set to BI_BITFIELDS.

bV5AlphaMask

Color mask that specifies the alpha component of each pixel.

bV5CSType

The color space of the DIB.

The following table specifies the values for bV5CSType.

Value Meaning
LCS_CALIBRATED_RGB This value implies that endpoints and gamma values are given in the appropriate fields.
LCS_sRGB Specifies that the bitmap is in sRGB color space.
LCS_WINDOWS_COLOR_SPACE This value indicates that the bitmap is in the system default color space, sRGB.
PROFILE_LINKED This value indicates that bV5ProfileData points to the file name of the profile to use (gamma and endpoints values are ignored).
PROFILE_EMBEDDED This value indicates that bV5ProfileData points to a memory buffer that contains the profile to be used (gamma and endpoints values are ignored).
 

See the LOGCOLORSPACE structure for information that defines a logical color space.

bV5Endpoints

A CIEXYZTRIPLE structure that specifies the x, y, and z coordinates of the three colors that correspond to the red, green, and blue endpoints for the logical color space associated with the bitmap. This member is ignored unless the bV5CSType member specifies LCS_CALIBRATED_RGB.

bV5GammaRed

Toned response curve for red. Used if bV5CSType is set to LCS_CALIBRATED_RGB. Specify in unsigned fixed 16.16 format. The upper 16 bits are the unsigned integer value. The lower 16 bits are the fractional part.

bV5GammaGreen

Toned response curve for green. Used if bV5CSType is set to LCS_CALIBRATED_RGB. Specify in unsigned fixed 16.16 format. The upper 16 bits are the unsigned integer value. The lower 16 bits are the fractional part.

bV5GammaBlue

Toned response curve for blue. Used if bV5CSType is set to LCS_CALIBRATED_RGB. Specify in unsigned fixed 16.16 format. The upper 16 bits are the unsigned integer value. The lower 16 bits are the fractional part.

bV5Intent

Rendering intent for bitmap. This can be one of the following values.

Value Intent ICC name Meaning
LCS_GM_ABS_COLORIMETRIC Match Absolute Colorimetric Maintains the white point. Matches the colors to their nearest color in the destination gamut.
LCS_GM_BUSINESS Graphic Saturation Maintains saturation. Used for business charts and other situations in which undithered colors are required.
LCS_GM_GRAPHICS Proof Relative Colorimetric Maintains colorimetric match. Used for graphic designs and named colors.
LCS_GM_IMAGES Picture Perceptual Maintains contrast. Used for photographs and natural images.

bV5ProfileData

The offset, in bytes, from the beginning of the BITMAPV5HEADER structure to the start of the profile data. If the profile is embedded, profile data is the actual profile, and it is linked. (The profile data is the null-terminated file name of the profile.) This cannot be a Unicode string. It must be composed exclusively of characters from the Windows character set (code page 1252). These profile members are ignored unless the bV5CSType member specifies PROFILE_LINKED or PROFILE_EMBEDDED.

bV5ProfileSize

Size, in bytes, of embedded profile data.

bV5Reserved

This member has been reserved. Its value should be set to zero.

Remarks

If bV5Height is negative, indicating a top-down DIB, bV5Compression must be either BI_RGB or BI_BITFIELDS. Top-down DIBs cannot be compressed.

The Independent Color Management interface (ICM) 2.0 allows International Color Consortium (ICC) color profiles to be linked or embedded in DIBs (DIBs). See Using Structures for more information.

When a DIB is loaded into memory, the profile data (if present) should follow the color table, and the bV5ProfileData should provide the offset of the profile data from the beginning of the BITMAPV5HEADER structure. The value stored in bV5ProfileData will be different from the value returned by the sizeof operator given the BITMAPV5HEADER argument, because bV5ProfileData is the offset in bytes from the beginning of the BITMAPV5HEADER structure to the start of the profile data. (Bitmap bits do not follow the color table in memory). Applications should modify the bV5ProfileData member after loading the DIB into memory.

For packed DIBs, the profile data should follow the bitmap bits similar to the file format. The bV5ProfileData member should still give the offset of the profile data from the beginning of the BITMAPV5HEADER.

Applications should access the profile data only when bV5Size equals the size of the BITMAPV5HEADER and bV5CSType equals PROFILE_EMBEDDED or PROFILE_LINKED.

If a profile is linked, the path of the profile can be any fully qualified name (including a network path) that can be opened using the CreateFile function.

Requirements

Requirement Value
Minimum supported client Windows 2000 Professional [desktop apps only]
Minimum supported server Windows 2000 Server [desktop apps only]
Header wingdi.h (include Windows.h)

See also

BITMAPINFO

BITMAPINFOHEADER

BITMAPV4HEADER

Bitmap Structures

Bitmaps Overview

CIEXYZTRIPLE

CreateDIBitmap

LOGCOLORSPACE

StretchDIBits