mlib_ImageConv3x3Index(3MLIB)

Name

mlib_ImageConv3x3Index - 3x3 convolution on a color indexed image

Synopsis

cc [ flag... ] file... –lmlib [ library... ]
#include <mlib.h>

mlib_status mlib_ImageConv3x3Index(mlib_image *dst, const mlib_image *src,
     const mlib_s32 *kernel, mlib_s32 scale, mlib_edge edge,
     const void *colormap);

Description

The mlib_ImageConv3x3Index() function performs a 3x3 convolution on the color indexed source image by using the user-supplied kernel.

The input and output images must have the same image type and size.

For this convolution, the key element of the convolution kernel is located at the center of the kernel matrix.

This function performs the convolution on color indexed image. The input image and the output image must be single-channel images. The image type must be MLIB_BYTE or MLIB_SHORT.

It uses the following equation:

               m-1-dm n-1-dn
dst[x][y][i] =  SUM    SUM  src[x+p][y+q][i]*k[p][q]*2**(-scale)
               p=-dm  q=-dn

where m = 3, n = 3, dm = (m - 1)/2 = 1, dn = (n - 1)/2 = 1.

Parameters

The function takes the following arguments:

dst

Pointer to destination image.

src

Pointer to source image.

kernel

Pointer to the convolution kernel, in row major order.

scale

Scaling factor.

edge

Type of edge condition. It can be one of the following:

MLIB_EDGE_DST_NO_WRITE
MLIB_EDGE_DST_FILL_ZERO
MLIB_EDGE_DST_COPY_SRC
MLIB_EDGE_SRC_EXTEND

colormap

Internal data structure for inverse color mapping. This data structure is generated by the mlib_ImageColorTrue2IndexInit() function. The source and destination images must be single-channel images.

Return Values

The function returns MLIB_SUCCESS if successful. Otherwise it returns MLIB_FAILURE.

Attributes

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE ATTRIBUTE VALUE Interface Stability Committed MT-Level MT-Safe

See also

mlib_ImageConv2x2(3MLIB), mlib_ImageConv2x2_Fp(3MLIB), mlib_ImageConv2x2Index(3MLIB), mlib_ImageConv3x3(3MLIB), mlib_ImageConv3x3_Fp(3MLIB), mlib_ImageConv4x4(3MLIB), mlib_ImageConv4x4_Fp(3MLIB), mlib_ImageConv4x4Index(3MLIB), mlib_ImageConv5x5(3MLIB), mlib_ImageConv5x5_Fp(3MLIB), mlib_ImageConv5x5Index(3MLIB), mlib_ImageConv7x7(3MLIB), mlib_ImageConv7x7_Fp(3MLIB), mlib_ImageConv7x7Index(3MLIB), mlib_ImageConvKernelConvert(3MLIB), mlib_ImageConvMxN(3MLIB), mlib_ImageConvMxN_Fp(3MLIB), mlib_ImageConvMxNIndex(3MLIB), mlib_ImageConvolveMxN(3MLIB), mlib_ImageConvolveMxN_Fp(3MLIB), mlib_ImageSConv3x3(3MLIB), mlib_ImageSConv3x3_Fp(3MLIB), mlib_ImageSConv5x5(3MLIB), mlib_ImageSConv5x5_Fp(3MLIB), mlib_ImageSConv7x7(3MLIB), mlib_ImageSConv7x7_Fp(3MLIB), mlib_ImageSConvKernelConvert(3MLIB), attributes(5)