haveImageReader function
Returns true if the specified image can be decoded by OpenCV.
https://docs.opencv.org/4.10.0/d4/da8/group__imgcodecs.html#ga65d3569d8845d1210e1aeab8c199031c
Implementation
bool haveImageReader(String filename) {
final cname = filename.toNativeUtf8().cast<ffi.Char>();
final rval = cimgcodecs.cv_haveImageReader(cname);
calloc.free(cname);
return rval;
}