TrueDistanceTransform
Calculates the Euclidean distance from each non-zero pixel to the nearest zero pixel within the source image.
The function interface is declared as follows:
HmppResult HMPPI_TrueDistanceTransform_8u32f_C1R(const uint8_t* pSrc, int srcStep, float* pDst, int dstStep, HmppiSize roiSize);
Parameters
Parameter |
Description |
Value Range |
Input/Output |
|---|---|---|---|
pSrc |
Pointer to the source vector |
The value cannot be NULL. |
Input |
srcStep |
Distance between starts of consecutive lines in the source image, in bytes |
(0, INT_MAX] |
Input |
pDst |
Pointer to the destination vector |
The value cannot be NULL. |
Output |
dstStep |
Distance between starts of consecutive lines in the destination image, in bytes |
(0, INT_MAX] |
Input |
roiSize |
Size of the ROI of the source and destination images, in pixels |
roiSize.width ∈ (0, INT_MAX], roiSize.height ∈ (0, INT_MAX] |
Input |
Return Value
- Success: HMPP_STS_NO_ERR
- Failure: An error code is returned.
Error Codes
Error Code |
Description |
|---|---|
HMPP_STS_NULL_PTR_ERR |
The value of pSrc, pDst, or pMetrics is NULL. |
HMPP_STS_STEP_ERR |
The value of srcStep is less than or equal to 0. |
HMPP_STS_SIZE_ERR |
The value of roiSize.width or roiSize.height is less than or equal to 0. |
Example
#include <stdio.h>
#include "hmppi.h"
#include "hmpp_type.h"
void TrueDistanceTransformExample()
{
HmppiSize roi = {5, 7};
uint8_t src[45] = {1, 0, 3, 4, 5,
1, 2, 3, 4, 5,
1, 2, 3, 4, 5,
1, 2, 0, 4, 5,
1, 2, 3, 4, 5,
1, 2, 3, 4, 5,
1, 2, 3, 4, 5,
1, 2, 3, 4, 0,
1, 2, 3, 4, 5
};
float dst[49] = {0};
int32_t srcStep = 5 * sizeof(uint8_t);
int32_t dstStep = 7 * sizeof(float);
HmppResult res = HMPPI_TrueDistanceTransform_8u32f_C1R(src, srcStep, dst, dstStep, roi);
printf("result: %d\n", (int)res);
for (int i = 0; i < 7; i++) {
for (int j = 0; j < 7; j++) {
printf("%.2f ", dst[i * 7 + j]);
}
printf("\n");
}
}
int main()
{
TrueDistanceTransformExample();
return 0;
}
Output:
result: 0 1.00 0.00 1.00 2.00 3.00 0.00 0.00 1.41 1.00 1.41 2.24 2.83 0.00 0.00 2.24 1.41 1.00 1.41 2.24 0.00 0.00 2.00 1.00 0.00 1.00 2.00 0.00 0.00 2.24 1.41 1.00 1.41 2.24 0.00 0.00 2.83 2.24 2.00 2.24 2.83 0.00 0.00 3.61 3.16 3.00 3.16 3.61 0.00 0.00