L_AddBitmapNoise

#include "l_bitmap.h"

L_INT EXT_FUNCTION L_AddBitmapNoise(pBitmap, uRange, uChannel)

pBITMAPHANDLE pBitmap;	/* pointer to the bitmap handle */
L_UINT uRange;	/* percentage of coverage */
L_UINT uChannel;	/* color plane constant */

Adds random pixels to a bitmap, letting you specify the percentage of coverage and the color plane.

Parameter	Description
pBitmap	Pointer to the bitmap handle referencing the bitmap to process.
uRange	Percentage of coverage, expressed in tenths of a percent. Valid values are 0 to 1000.
uChannel	Possible values are:
	Value	Meaning
	CHANNEL_MASTER	[0] All channels.
	CHANNEL_RED	[1] Red channel only.
	CHANNEL_GREEN	[2] Green channel only.
	CHANNEL_BLUE	[3] Blue channel only.

Returns

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

Comments

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

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.

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.

Use this function in order to add random noise to a bitmap.

Use the L_PerlinBitmap function to use a pseudo-random number generator in order to create a Perlin noise, and then procedurally transform that noise into a texture. Depending on the flags that are set, the texture can be saved as a bitmap by itself, or the texture can be combined with another bitmap. For more information, refer to Using the L_PerlinBitmap function.

Use the L_CloudsBitmap function in order to use Perlin equations to generate pseudo-random noise, and then procedurally transform that noise into a cloud-like texture. The L_CloudsBitmap function applies equations to the Perlin noise that are different than those used by the L_PerlinBitmap 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_SharpenBitmap, L_PosterizeBitmap, L_MosaicBitmap, L_EmbossBitmap, L_AverageFilterBitmap, L_MedianFilterBitmap, L_IntensityDetectBitmap, L_SpatialFilterBitmap, L_BinaryFilterBitmap, L_MaxFilterBitmap, L_MinFilterBitmap, L_OilifyBitmap, L_SolarizeBitmap, L_DlgAddNoise, L_WindowLevel, L_BumpMapBitmap, L_CubismBitmap, L_DrawStarBitmap, L_DryBitmap, L_FreePlaneBendBitmap, L_FreeRadBendBitmap, L_GlassEffectBitmap, L_GlowFilterBitmap, L_LensFlareBitmap, L_LightBitmap, L_OceanBitmap, 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_AddShadowBitmap, L_RevEffectBitmap, L_AgingBitmap, L_DiceEffectBitmap, L_FunctionalLightBitmap, L_PuzzleEffectBitmap, L_RingEffectBitmap, L_TextureAlphaBlendBitmap, L_BricksTextureBitmap, L_DeskewBitmap, L_DeskewBitmapExt, L_DiffuseGlowBitmap, L_GlowFilterBitmap, L_HalfTonePatternBitmap, L_HighPassFilterBitmap, L_MaskConvolutionBitmap, L_PerspectiveBitmap, L_PlasmaFilterBitmap, L_PointillistBitmap
Topics:	Raster Image Functions: Filtering Images
	Applying Artistic Effects

Example

For complete sample code, refer to the CHILD.C module of the DEMO example.

/* This example loads a bitmap and adds red noise to it. */
BITMAPHANDLE LeadBitmap; /* Bitmap handle to hold the loaded image. */
/* Load the bitmap, keeping the bits per pixel of the file */
L_LoadBitmap (TEXT("IMAGE1.CMP"), &LeadBitmap, sizeof(BITMAPHANDLE), 0, ORDER_BGR, NULL, NULL);
/* Add red noise with 25 percent coverage */
L_AddBitmapNoise(&LeadBitmap, 250, CHANNEL_RED);