This C++ program uses the built-in camera or any connected camera to perform image treatments. The image manipulations are performed by OpenCV and the interface is managed by Qt. This multithreaded program launches a thread dedicated to image processing and another thread to pure Qt display.
The implemented image manipulations are:
- Black and white + colour inversion
- Blur filters
- Simple
- Gaussian
- Median
- Bilateral
- Morphological filters
- Erode + Dilate
- Opening + Closing
- Morphological gradient + Top hat + Black hat
- Hit / Miss
- Threshold
- Global threshold (binary, binary inverted, truncate, to zero, to zero inverted, Otsu, triangle method)
- Adaptive threshold (mean and Gaussian)
- Histogram equalization (global + CLAHE)
- Edge detectors (Sobel derivatives, Laplacian and Canny edge detector)
- Face recognition
- Object recognition (Hough line, Hough circle and Harris corner detection)
- Image stitching to create a panorama
- Motion detection (Farneback dense optical flow and foreground extraction)
- Module Photo
- Contrast Preserving Decolorization
- Denoizing (Non-Local Means)
- Non-Photorealistic Rendering (Edge preserving, Detail enhancing, Pencil sketch, Stylization)
- White balancing (from module xphoto)
- Barcode and QR code decoder (through the external library ZBar)
- Text detection and recognition through OpenCV EAST text detector and the library Tesseract
This code requires an installed version of OpenCV. The program is linked against the following libraries of OpenCV:
- libopencv_core
- libopencv_imgcodecs
- libopencv_highgui
- libopencv_videoio
- libopencv_imgproc
- libopencv_video
- libopencv_photo
The code can also be compiled against four optional libraries:
- libopencv_objdetect (enables face detection)
- libopencv_stitching (enables the panorama creation)
- libopencv_xphoto (enables features from xphoto)
- libzbar (enables decryption of barcodes and QR codes)
- libtesseract (enables text recognition inside images)
If you don't have these libraries, just comment the top lines in the file Video.pro. If you have the objdetect library, a face-detetection cascade from OpenCV is also required. In this program the face-detection cascade file is hard-coded as "opencv-4.3.0/data/haarcascades/haarcascade_frontalface_default.xml" in the file capturevideo.cpp. This path must be adapted according to your installation. The ZBar library must also be compiled in order to be able to decode the barcodes / QR codes. For this library to function, it is not mandatory to compile ZBar with gtk, python or qt4 options enabled (only the headers and the library are required, not the executable).
You must have Qt5 in order to fully take advantage of multithreading. If you only have Qt4, please download version 1.0 of this program.
Your C++ compiler must accept c++11 directives.
I developed this program on a old Mac. The graphic card supports only OpenCL 1.0 directives, which is not sufficient for for image stitching. Luckily my CPU manages version 1.2 of OpenCL. To set OpenCL to use the CPU, I had to export the environment variable OPENCV_OPENCL_DEVICE=":CPU:0". Moreover if your program complains about not finding OpenCV libraries, don't forget to export the path to the OpenCV libraries in the environment variable DYLD_LIBRARY_PATH.
Edit the file Video.pro and provide the path where your OpenCV, ZBar and Tesseract libraries are installed. To create a Makefile or a XCode project, run the Qt command:
qmake Video.pro
to generate a Makefile, which is used to compile the project.
Not tested. Should be similar to what is done for MacOS. Modify the file Video.pro accordingly to your availabilities and launch
qmake Video.pro
Generating a Makefile through qmake has never been so easy. Simply modify the file Video.pro and execute
qmake.exe Video.pro
to generate a Makefile (MinGW) or a project for VisualStudio. Don't forget to put the required *.dll libraries in the same directory as the executable before launching it! The list of required libraries is
- OpenCV: opencv_calib3d430.dll opencv_core430.dll opencv_face430.dll opencv_features430.dll opencv_flann430.dll opencv_imgcodecs430.dll opencv_imgproc430.dll opencv_objdetect430.dll opencv_photo430.dll opencv_stitching430.dll opencv_video430.dll opencv_video_ffmpeg430_64.dll opencv_videoio430.dll opencv_xphoto430.dll
- ZBar: libzbar-0.dll
- Tesseract: tesseract41.dll opencv_dnn430.dll
- Qt5: Qt5Core.dll Qt5Gui.dll Qt5Multimedia.dll Qt5Network.dll Qt5Widgets.dll
Stitching operation done on my laptop with application of the Stylization filter from the module Photo / Non-Photorealistic Rendering
