LOCALHISTOEQUALIZEDLGPARAMS

typedef struct _LOCALHISTOEQUALIZEDLGPARAMS
{
   L_UINT uStructSize;
   pBITMAPHANDLE pBitmap;
   L_BOOL bZoomToFit;
   L_INT nWidth;
   L_INT nHeight;
   L_INT nXExtention;
   L_INT nYExtention;
   L_UINT uType;
   L_UINT uSmooth;
   L_UINT32 uDlgFlags;
   LTCOMMDLGHELPCB pfnHelpCallback;
   L_VOID L_FAR *pHelpCallBackUserData;
} LOCALHISTOEQUALIZEDLGPARAMS, L_FAR * LPLOCALHISTOEQUALIZEDLGPARAMS;

The LOCALHISTOEQUALIZEDLGPARAMS structure provides information used to initialize the dialog box created by the L_DlgLocalHistoEqualize function. After the user closes the dialog box, this structure is updated with information about the user's selections.

Member

Description

uStructSize

Size of this structure, in bytes. Use the sizeof operator to calculate this value.

pBitmap

Pointer to the bitmap handle that references the bitmap used for preview or processing.

bZoomToFit

Flag that indicates the initial zoom level for previewing the image. Possible values are:

 

Value

Meaning

 

TRUE

Set the initial zoom level to "Zoom to fit".

 

FALSE

Set the initial zoom level to "Normal (1:1)".

nWidth

The width of the local histogram equalizer rectangle, in pixels. The width should be more than zero.

nHeight

The height of the local histogram equalizer rectangle, in pixels. The height should be more than zero.

nXExtention

The extension of the width of the local histogram equalizer rectangle, in pixels.

nYExtention

The extension of the height of the local histogram equalizer rectangle, in pixels.

uType

Flag that indicates which color space to equalize. Possible values are:

 

Value

Meaning

 

RGB_SPACE

[0x0001] Linearize the number of pixels across the RGB color space. (Separated channels)

 

YUV_SPACE

[0x0002] Linearize the number of pixels across the YUV color space. (Best results)

 

GRAY_SPACE

[0x0004] Linearize the number of pixels per gray level in a gray level representation of the image.

 

uSmooth

Size of the area to be used when smoothing the edges between localized blocks. Possible values range from 0 to 7, but if nHeight is less than or equal to 7 then the maximum value for this item is nHeight - 1.

uDlgFlags

User interface flags for this dialog, which determine the layout and action of the dialog. Possible values are:

 

Value

Meaning

 

DLG_LOCALHISTOEQUALIZE_AUTOPROCESS

[0x00000001] process the image on OK. The pBitmap member of this structure should contain a valid bitmap.

 

DLG_LOCALHISTOEQUALIZE_SHOW_CONTEXTHELP

[0x00000002] dialog should contain a context sensitive help icon.

 

DLG_LOCALHISTOEQUALIZE_SHOW_PREVIEW

[0x00000004] show a preview of the image in the dialog. The pBitmap member of this structure should contain a valid bitmap.

 

DLG_LOCALHISTOEQUALIZE_SHOW_TOOL_ZOOMLEVEL

[0x00000008] show the "Zoom to fit" and "Zoom Normal" toolbar buttons. The DLG_LOCALHISTOEQUALIZE_SHOW_PREVIEW flag must be set in order to show these buttons.

 

DLG_LOCALHISTOEQUALIZE_SHOW_APPLY

[0x00000080] Show the Apply button in the dialog. The dialog will not apply any effect unless the user presses the Apply button.

pfnHelpCallback

Pointer to an optional help callback function. If you do not wish to provide help to this dialog, use NULL as the value of this parameter. To provide help to this dialog, use the function pointer as the value of this parameter. The callback function must adhere to the prototype described in LTCOMMDLGHELPCB.

pHelpCallBackUserData

Void pointer that you can use to pass one or more additional parameters that the callback function needs. To use this feature, assign a value to a variable or create a structure that contains as many fields as you need. Then, in this parameter, pass the address of the variable or structure, casting it to L_VOID L_FAR *. The callback function, which receives the address in its own pHelpCallBackUserData parameter, can cast it to a pointer of the appropriate data type to access your variable or structure. If the additional parameters are not needed, you can pass NULL in this parameter.