How to write MP4 with OpenCV3

When trying to write MP4 file (H264), I tired code of

And I got error saying:

This problem is solved by changing the fourcc to the ASCII number directly to cv2.VideoWriter(), i.e.


Install Dlib on Visual Studio 2015

Step1: Download Dlib

Step2: Use cmake to generate library

  • Use cmake to build the library. Set the directories as shown in the Figure 1 below
  • Click “Generate” and set the configuration as shown in Figure 2
  • Click “Finish”
  • Go to “C:/Users/xmeng525/Dropbox/OPENCV_STUDY/dlib-19.4/build”, open the Dlib solution
  • Run the “ALL_BUILD” project to under “Release x64” and “Debug x64”
  • You will get “Debug” and “Release” folders as shown in Figure 3, containing “dlib.lib”


















Figure 1












Figure 2

Figure 3

Step3: Build a new win32 console Application for testing.

  • Add “VC++ Directories”
  • Change “C/C++ / General”
  • Change “C/C++ / Preprocessor”, add “DLIB_JPEG_SUPPORT” and “DLIB_PNG_SUPPORT”
  • Change “Linker/General/Additional Library Directories” to the directory with “Dlib.lib”
  • Change “Linker/ Input”

Step4: Testing.

  • Build a testing file “face_landmark_detection_ex.cpp” as shown in the figure below.
  • Copy the following code to the main file


  • Run, if there is error:

    • Go to C:\Users\xmeng525\Dropbox\OPENCV_STUDY\dlib-19.4\dlib\threads\threads_kernel_shared.h
    • Comment the following code:

Step5: Get results

Store array to Mat








CV_8SC1 -> char

CV_8UC1 -> unsigned char

CV_16SC1 -> short

CV_16UC1 -> unsigned short

CV_32SC1 -> int

CV_32FC1 -> float

CV_64FC1 -> double