References ▼
The BITMAPHANDLE structure serves as a working area for image manipulation and conversion. LEADTOOLS functions use this structure as a bitmap handle for accessing the image in memory and for maintaining the characteristics of the image.
Note: |
Fields intended for internal use, such as the pointer to the bitmap, are omitted from the table. If necessary, you can refer to the LTKRN.H header file which describes the entire structure. |
Member |
Data Type |
Description |
Width |
Image width in pixels. |
|
Height |
Image height in pixels. |
|
BitsPerPixel |
Number of bits per pixel. |
|
BytesPerLine |
Bytes per line, rounded upward to the nearest multiple of four. |
|
Flags.Allocated |
TRUE if the bitmap is allocated. |
|
Flags.ConventionalMemory |
TRUE if the bitmap is allocated using conventional memory. |
|
Flags.DiskMemory |
TRUE if the bitmap is allocated using LEAD's own virtual memory. |
|
Flags.LockedMemory |
TRUE if the bitmap memory is locked down. |
|
Flags.Progressive |
TRUE if an image is being loaded from a progressive JPEG file. |
|
Flags.WaitUserInput |
TRUE if the animation playback waits for user input. |
|
Flags.Transparency |
TRUE if the animation playback uses transparency. |
|
Flags.Compressed |
TRUE if the current bitmap is in 1-bit RLE-compressed format. For information about this format, refer to Speeding Up 1-Bit Documents. |
|
Flags.Signed |
TRUE if the pixel values in the bitmap are signed. |
|
nColors |
Number of colors (256 or less) that the bitmap has. If the image has more than 256 colors, this value is zero. |
|
hPalette |
HPALETTE |
Handle to the image's palette. It can be an optimized palette or a fixed palette. |
ViewPerspective |
Where the beginning of the image is stored. Valid values are TOP_LEFT, BOTTOM_LEFT, TOP_RIGHT, BOTTOM_RIGHT, TOP_LEFT90, and TOP_LEFT270. For descriptions, refer to Accounting for View Perspective. |
|
Order |
Color order of the bitmap. Possible values are ORDER_RGB, ORDER_BGR and ORDER_GRAY. |
|
Size |
Size of the bitmap image data, in bytes. |
|
LoadRow |
The number of the current row during a load, when an image is being loaded from a progressive JPEG file. |
|
DitheringMethod |
Dithering method (referenced by some functions). For possible values, refer to the L_DefaultDithering function. |
|
XResolution |
Horizontal resolution, in dots per inch. Some file formats save this value in the file header. |
|
YResolution |
Vertical resolution, in dots per inch. Some file formats save this value in the file header. |
|
Left |
Left offset for animation playback. |
|
Top |
Top offset for animation playback, based on a TOP_LEFT view perspective. |
|
Delay |
Animation playback delay in milliseconds (ms). |
|
Background |
COLORREF |
Background color for animation playback. You can specify a COLORREF value, such as the return value of the Windows RGB macro, or you can use the PALETTEINDEX macro to specify a palette color. |
Transparency |
COLORREF |
Transparent color for animation playback. You can specify a COLORREF value, such as the return value of the Windows RGB macro, or you can use the PALETTEINDEX macro to specify a palette color. |
DisposalMethod |
Animation playback disposal method. For possible values, refer to Animation Disposal Methods. |
|
LowBit |
Value indicating the low bit used for window leveling. 0 <= nLowBit <= nHighBit <= (11 for 12-bit grayscale or 15 for 16-bit grayscale). A value of -1 will be treated as 0. |
|
HighBit |
Value indicating the high bit used for window leveling. 0 <= nLowBit <= nHighBit <= (11 for 12-bit grayscale or 15 for 16-bit grayscale). A value of -1 will be treated as BitsPerPixel -1. |
|
MinVal |
Minimum grayscale value. For every value between 0 and MinVal, Black (RGB(0,0,0)) will be used. For values between MinVal and MaxVal, the gray value to be displayed is calculated by : gray = (index - MinVal) * 255 / (MaxVal - MinVal).(See * below) |
|
MaxVal |
Maximum grayscale value. For every value larger than MaxVal, White (RGB(255,255,255)) will be used. For values between MinVal and MaxVal, the gray value to be displayed is calculated by : gray = (index - MinVal) * 255 / (MaxVal - MinVal). (See * below) |
* index is the intensity value of the pixel. If the intensity value is > MaxVal, the color will be White. If the intensity value is < MinVal, the color will be Black. For those intensity values between MinVal and MaxVal, the above equation is used to determine the color, with index equal to the intensity value.
pBITMAPHANDLE is a pointer to a BITMAPHANDLE structure. Generally, where a function parameter type is pBITMAPHANDLE, you can declare a BITMAPHANDLE variable, update the structure's fields, and pass the variable's address in the parameter. Declaring a pBITMAPHANDLE variable is necessary only if your program requires a pointer.
In most cases, the values of fields in the BITMAPHANDLE structure are maintained by LEADTOOLS functions.