[openvx] VX for basic use of objects_ distribution

1. Program source code

#include <iostream>
#include <VX/vx.h>

void print_distribution(vx_distribution distribution, const char *message)
{
    
    std::cout << "===============================" << std::endl;
    std::cout << message << std::endl;

    vx_size dimensions;
    vxQueryDistribution(distribution, (vx_enum)VX_DISTRIBUTION_DIMENSIONS, &dimensions, sizeof(dimensions));

    vx_int32 offset;
    vxQueryDistribution(distribution, (vx_enum)VX_DISTRIBUTION_OFFSET, &offset, sizeof(offset));

    vx_uint32 range; //  Need to be for bins Multiple 
    vxQueryDistribution(distribution, (vx_enum)VX_DISTRIBUTION_RANGE, &range, sizeof(range));

    vx_size bins; // BIN The number of 
    vxQueryDistribution(distribution, (vx_enum)VX_DISTRIBUTION_BINS, &bins, sizeof(bins));

    vx_uint32 window; // BIN Width  window=RANGE/BINS
    vxQueryDistribution(distribution, (vx_enum)VX_DISTRIBUTION_WINDOW, &window, sizeof(window));

    vx_size size; //  Total bytes 
    vxQueryDistribution(distribution, (vx_enum)VX_DISTRIBUTION_SIZE, &size, sizeof(size));

    std::cout << "dimensions : " << dimensions << std::endl;
    std::cout << "offset : " << offset << std::endl;
    std::cout << "range : " << range << std::endl;
    std::cout << "bins : " << bins << std::endl;
    std::cout << "window : " << window << std::endl;
    std::cout << "size : " << size << std::endl;

    vx_map_id map_id;
    void* ptr;
    //  The output address is  vx_uint32  Array of , The number of  VX_DISTRIBUTION_BINS  The return value of 
    std::cout << "item : " << std::endl;
    vxMapDistribution(distribution, &map_id, &ptr, VX_READ_ONLY, VX_MEMORY_TYPE_HOST, 0);
    for (int i = 0; i < bins; ++i) {
    
        std::cout << "\t" << "index: " << i << ", value: " << ((vx_uint32*)ptr)[i] << std::endl;
    }
    vxUnmapDistribution(distribution, map_id);
}

int main(int argc, char *argv[])
{
    
    (void) argc;
    (void) argv;

    vx_status status;
    vx_context context = vxCreateContext();

    vx_size bins = 64;
    vx_uint32 offset = 0U;
    vx_uint32 range = 256U;
    vx_distribution distribution = vxCreateDistribution(context, bins, offset, range);
    print_distribution(distribution, "create");

    vx_uint32* array = new vx_uint32 [bins];
    for (int i = 0; i < bins; ++i) {
    
        array[i] = i;
    }
    vxCopyDistribution(distribution, array, VX_WRITE_ONLY, VX_MEMORY_TYPE_HOST);
    print_distribution(distribution, "update");
    delete[] array;

    vxReleaseDistribution(&distribution);
    vxReleaseContext(&context);
    return EXIT_SUCCESS;
}

2. Running results

===============================
create
dimensions : 1
offset : 0
range : 256
bins : 64
window : 4
size : 256
item :
index: 0, value: 0
index: 1, value: 0
index: 2, value: 0
index: 3, value: 0
index: 4, value: 0
index: 5, value: 0
index: 6, value: 0
index: 7, value: 0
index: 8, value: 0
index: 9, value: 0
index: 10, value: 0
index: 11, value: 0
index: 12, value: 0
index: 13, value: 0
index: 14, value: 0
index: 15, value: 0
index: 16, value: 0
index: 17, value: 0
index: 18, value: 0
index: 19, value: 0
index: 20, value: 0
index: 21, value: 0
index: 22, value: 0
index: 23, value: 0
index: 24, value: 0
index: 25, value: 0
index: 26, value: 0
index: 27, value: 0
index: 28, value: 0
index: 29, value: 0
index: 30, value: 0
index: 31, value: 0
index: 32, value: 0
index: 33, value: 0
index: 34, value: 0
index: 35, value: 0
index: 36, value: 0
index: 37, value: 0
index: 38, value: 0
index: 39, value: 0
index: 40, value: 0
index: 41, value: 0
index: 42, value: 0
index: 43, value: 0
index: 44, value: 0
index: 45, value: 0
index: 46, value: 0
index: 47, value: 0
index: 48, value: 0
index: 49, value: 0
index: 50, value: 0
index: 51, value: 0
index: 52, value: 0
index: 53, value: 0
index: 54, value: 0
index: 55, value: 0
index: 56, value: 0
index: 57, value: 0
index: 58, value: 0
index: 59, value: 0
index: 60, value: 0
index: 61, value: 0
index: 62, value: 0
index: 63, value: 0

===============================
update
dimensions : 1
offset : 0
range : 256
bins : 64
window : 4
size : 256
item :
index: 0, value: 0
index: 1, value: 1
index: 2, value: 2
index: 3, value: 3
index: 4, value: 4
index: 5, value: 5
index: 6, value: 6
index: 7, value: 7
index: 8, value: 8
index: 9, value: 9
index: 10, value: 10
index: 11, value: 11
index: 12, value: 12
index: 13, value: 13
index: 14, value: 14
index: 15, value: 15
index: 16, value: 16
index: 17, value: 17
index: 18, value: 18
index: 19, value: 19
index: 20, value: 20
index: 21, value: 21
index: 22, value: 22
index: 23, value: 23
index: 24, value: 24
index: 25, value: 25
index: 26, value: 26
index: 27, value: 27
index: 28, value: 28
index: 29, value: 29
index: 30, value: 30
index: 31, value: 31
index: 32, value: 32
index: 33, value: 33
index: 34, value: 34
index: 35, value: 35
index: 36, value: 36
index: 37, value: 37
index: 38, value: 38
index: 39, value: 39
index: 40, value: 40
index: 41, value: 41
index: 42, value: 42
index: 43, value: 43
index: 44, value: 44
index: 45, value: 45
index: 46, value: 46
index: 47, value: 47
index: 48, value: 48
index: 49, value: 49
index: 50, value: 50
index: 51, value: 51
index: 52, value: 52
index: 53, value: 53
index: 54, value: 54
index: 55, value: 55
index: 56, value: 56
index: 57, value: 57
index: 58, value: 58
index: 59, value: 59
index: 60, value: 60
index: 61, value: 61
index: 62, value: 62
index: 63, value: 63