[ncnn] - the meaning of - 23300 in param

ncnn

1. -23300 It means

stay ncnn In the structural parameters of the model , Yes -23300 Parameters of , Such as ：

code
Slice Split_394 1 2 886 887 888 -23330=8,3,40,40,80,3,40,40,32 -23300=2,80,-233

This means = The following parameter is an array parameter ,2,80,-233 Express 2 A variable ,80,-233.

Code when parsing ：

bool is_array = id <= -23300;
if (is_array)
{
    
    id = -id - 23300;
}

if (id >= NCNN_MAX_PARAM_COUNT)
{
    
    NCNN_LOGE("id < NCNN_MAX_PARAM_COUNT failed (id=%d, NCNN_MAX_PARAM_COUNT=%d)", id, NCNN_MAX_PARAM_COUNT);
    return -1;
}

if (is_array)
{
    
    int len = 0;
    int nscan = dr.scan("%d", &len);
    if (nscan != 1)
    {
    
        NCNN_LOGE("ParamDict read array length failed");
        return -1;
    }

• When parsing, it will pass id = -id - 23300, take id Set as 0.

2. -233 It means

here -233 The specific meaning of the value depends on the specific layer Defined in . such as slice layer in ：

int q = 0;
for(size_t i = 0; i < top_blobs.size(); i++)
{
    
    int slice = slices_ptr[i];
    if (slice == -233)
    {
    
        slice = static_cast<int>((channels - q) / (top_blobs.size() - i));
    }

    Mat& top_blob = top_blobs[i];
    top_blob.create(w, h, slice, elemsize, opt.blob_allocator);
    if (top_blob.empty())
        return -100;

    int size = static_cast<int>(bottom_blob.cstep * slice);

    const unsigned char* ptr = bottom_blob.channel(q);
    unsigned char* outptr = top_blob;
    memcpy(outptr, ptr, size * elemsize);

    q += slice;
}

This is equivalent to the average split.