vc14/15 is VS 2015/2017.
vc16 is VS 2019.
DLDT is some intel deep learning thingy they conveniently added to the build.
debug or not,… your choice. should match how you build your own program (debug/release).
- vc14_vc15 should be compatible with VS 2015-2019, it is built with default optimization level (SSSE3) and should work on most PCs.
- dldt-2021.3-vc16-avx2 is special build integrated with open-source version of OpenVINO toolkit (AKA InferenceEngine, AKA DLDT), dnn and gapi modules can use this backend to infer some DL networks on CPU, iGPU and MyriadX devices (by Intel). The package is built with AVX2 optimization level and will work only on HW which support this instruction set. More info here: Intel's Deep Learning Inference Engine backend · opencv/opencv Wiki · GitHub