L_GlowFilterBitmap

#include "l_bitmap.h"

L_INT EXT_FUNCTION L_GlowFilterBitmap(pBitmap, uDim, uBright, uThreshold)

pBITMAPHANDLE pBitmap;	/* pointer to the bitmap handle */
L_UINT uDim;	/* size of the neighborhood */
L_UINT uBright;	/* brightness factor */
L_UINT uThreshold;	/* threshold value */

Makes the colored edges shine with a neon glow. This function is available in the Raster Pro and above toolkits.

Parameter	Description
pBitmap	Pointer to the bitmap handle that references the bitmap on which to apply the effect.
uDim	Size of the neighborhood used to determine the width of the glow.
uBright	Brightness factor used to create the "glow". This can be any number that is 0 or greater. If it is 0 the image will be black.
uThreshold	Threshold value used to determine which pixels are edge pixels. If the difference determined for a pixel is greater than this value, the pixel is an edge pixel. Valid values range from 0 through 65535 for 64-bit, 48-bit and 16-bit grayscale images and from 0 through 4095 for 12-bit grayscale images. Otherwise, it is from 0 to 255. Use this parameter to control the number of edge pixels found.

Returns

SUCCESS	The function was successful.
< 1	An error occurred. Refer to Return Codes.

Comments

This function detects the edge pixels by comparing the values of the pixel with surrounding pixels and if the edge value (the difference between the surrounding pixels and the pixel being evaluated) is greater than the Threshold value, the pixel is an edge pixel. The function then multiplies the values for the edge pixels by the uBright Brightness factor.

This function supports 12- and 16-bit grayscale and 48- and 64-bit color images. Support for 12- and 16-bit grayscale and 48- and 64-bit color images is available only in the Document/Medical toolkits.

To update a status bar or detect a user interrupt during execution of this function, refer to L_SetStatusCallback.

For an example, see the following figure:

$image\Glow_before.gif$

The following figure shows the same bitmap, after the effect has been applied:

$image\Glow_after.gif$

To obtain this effect, the following settings were used with the function:

uDim = 15;
uBright = 5;
uThreshold = 0;

This function does not support signed data images. It returns the error code ERROR_SIGNED_DATA_NOT_SUPPORTED if a signed data image is passed to this function.

Required DLLs and Libraries

LTIMG

For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application.

Platforms

Windows 95 / 98 / Me, Windows 2000 / XP.

See Also

Functions:	L_AddBitmapNoise, L_EmbossBitmap, L_MosaicBitmap, L_MotionBlurBitmap, L_OilifyBitmap, L_PosterizeBitmap, L_RemoveRedeyeBitmap, L_SolarizeBitmap, L_UnderlayBitmap, L_BumpMapBitmap, L_CubismBitmap, L_DrawStarBitmap, L_FreePlaneBendBitmap, L_FreeRadBendBitmap, L_DryBitmap, L_OceanBitmap, L_GlassEffectBitmap, L_LensFlareBitmap, L_LightBitmap, L_PlaneBendBitmap, L_PlaneBitmap, L_SampleTargetBitmap, L_TunnelBitmap, L_BendingBitmap, L_CylindricalBitmap, L_FreeHandShearBitmap, L_FreeHandWaveBitmap, L_ImpressionistBitmap, L_PixelateBitmap, L_PolarBitmap, L_PunchBitmap, L_RadialBlurBitmap, L_RadWaveBitmap, L_RippleBitmap, L_SpherizeBitmap, L_SwirlBitmap, L_WaveBitmap, L_WindBitmap, L_ZoomBlurBitmap, L_ZoomWaveBitmap, L_AdjustBitmapTint, L_ColorHalfToneBitmap, L_DiffuseGlowBitmap, L_HighPassFilterBitmap, L_MaskConvolutionBitmap
Topics:	Raster Image Functions: Filtering Images
	Raster Image Functions: Artistic Effects
	Applying Artistic Effects
	Raster Image Functions: Detecting and Enhancing Edges and Lines
	Raster Image Functions: Correcting Colors

Example

BITMAPHANDLE LeadBitmap; /* Bitmap handle for the image */

/* Load a bitmap at its own bits per pixel */
L_LoadBitmap(TEXT("IMAGE3.CMP"), &LeadBitmap, sizeof(BITMAPHANDLE), 0, ORDER_BGR, NULL, NULL);

/* Apply glow effect on the image*/
L_GlowFilterBitmap (&LeadBitmap, 5, 3, 0);