Install Dlib on macOS

[macOS Mojave 10.14.3] Setup environment for Opencv4.0.1 C++ develop

• Install dlib by brew

brew cask install xquartz
brew install gtk+3 boost
brew install dlib

dlib installed at: /usr/local/Cellar/dlib/19.17

• Get Dlib’s include directory

pkg-config --libs --cflags dlib-1

• [Optional] Compile manually: http://dlib.net/compile.html
• Example CMakeLists.txt for OpenCV and dlib

# cmake needs this line
cmake_minimum_required(VERSION 3.13)

# Enable C++11
set(CMAKE_CXX_STANDARD 11)
set(CMAKE_CXX_STANDARD_REQUIRED TRUE)

if(NOT CMAKE_BUILD_TYPE AND NOT (MSVC_IDE OR XCODE))
    set(CMAKE_BUILD_TYPE Release CACHE STRING "Build type, one of: Release, Debug" FORCE)
endif()

# Set target name, change with your favorite name
project(nc-rd-facemask CXX)

message( STATUS "Build type: ${CMAKE_BUILD_TYPE}" )
message( STATUS "Configuration types: ${CMAKE_CONFIGURATION_TYPES}" )

# Detect 64 or 32 bit
if (CMAKE_SIZEOF_VOID_P EQUAL 8)
    # 64-bit project
    SET(64_BIT_OS TRUE)
    message( STATUS "A 64-bit OS detected" )
else()
    SET(64_BIT_OS FALSE)
    message( STATUS "A 32-bit OS detected" )
endif()

# Find OpenCV, you may need to set OpenCV_DIR variable
# to the absolute path to the directory…