How to use Pi Camera with OpenCV for Raspberry Pi?

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Raspberry Pi 2 with Pi Camera

Normally OpenCV only supports USB camera for raspberry pi, if you want to use OpenCV with Pi camera, I have a nice guide for you.

Before we set the Pi camera, you have to install OpenCV library firstly, you can follow my previous guide.

I use the RaspiCam library from Rafael Muñoz Salinas (very good job, easy installation and fast speed), it provides C++ API for us, frame per second is 30.

1. Plug Pi camera into Raspberry Pi.

2. Download RaspiCam library into your Pi.

3. Install the library.

tar xvzf raspicam-0.1.3.tgz (uncompress the file)

cd raspicam-0.1.3 (go to the library folder)

mkdir build

cd build

cmake ..

make

sudo make install

4. Testing

The library provides cmake to compile the program, but it’s not convenient for me, so I wrote makefile to compile the program.Here is the makefile:

LIBS = -I/usr/local/include/ 
CFLAGS = -lraspicam -lraspicam_cv -lopencv_core -lopencv_highgui
objects= main.o camera.o

picam: $(objects) 
	g++ $(objects) -o picam $(LIBS)$(CFLAGS)

main.o: main.cpp camera.h
	g++ main.cpp -c

camera.o: camera.cpp camera.h
	g++ camera.cpp -c
	
.PHONY: clean
clean:
	rm picam $(objects)

The library provides some examples to us, I rewrote the sample code, actually we also can use OpenCV C API(I transfer cv::Mat to IplImage in sample code).

Here is sample code(GitHub), download to your raspberry pi, make and run the program, FPS is 30(CPU usage is 22%), amazing!