videostreamer.cpp

#include "videostreamer.h"
#include "ui_videostreamer.h"
#include <QPainter>
#include <QDebug>
#include <QByteArray>
#include <opencv2/core/core.hpp>
#include <opencv2/imgproc/imgproc.hpp>
#include <opencv2/highgui/highgui.hpp>

VideoStreamer::VideoStreamer(v4l2_device_param param, bool mainCamera, QWidget *parent) :
  QMainWindow(parent),
  ui(new Ui::VideoStreamer),
  _capture(new V4L2Device(param))
{
  ui->setupUi(this);

  _width =  (int) _capture->getWidth();
  _height = (int) _capture->getHeight();
  _stride = (int) _capture->getStride();

  if (mainCamera) {

      _capture->setCallback([&](const Buffer& buffer, const struct v4l2_buffer& buffer_info) {

          QImage img = QImage(_width, _height, QImage::Format_RGB888);

          unsigned char *rgb_data = img.bits();

          v4lconvert_yuyv_to_rgb24((const unsigned char*) buffer.data, rgb_data, _width, _height, _stride);

          emit renderedImage(img);

        });

    } else {

      _capture->setCallback([&](const Buffer& buffer, const struct v4l2_buffer& buffer_info) {

          cv::Mat bayer8 =  cv::Mat(_height, _width, CV_8UC1, (uchar*) buffer.data);
          cv::Mat rgb8 =  cv::Mat(_height, _width, CV_8UC3);

          cv::cvtColor(bayer8, rgb8, CV_BayerGB2RGB);

          cv::Mat result = cv::Mat(_height, _width, CV_8UC3);

          cv::cvtColor(rgb8, result, CV_BGR2RGB);

          QImage img = QImage((const uchar*) result.data, result.cols,
                              result.rows, result.step1(), QImage::Format_RGB888);

          img.bits();

          emit renderedImage(img);
        });
    }

  // connect rendered image signal to set picture slot
  connect(this, SIGNAL(renderedImage(QImage)), this, SLOT(setPicture(QImage)));

  setAutoFillBackground(true);
}

void VideoStreamer::paintEvent(QPaintEvent *event) {
  QPainter painter(this);
  painter.setPen(Qt::white);
  painter.setFont(QFont("Arial", 30));
  painter.drawText(rect(), Qt::AlignCenter, "Qt");
  painter.drawPixmap(this->rect(), pixmap);
}

void VideoStreamer::setPicture(const QImage& image) {

  pixmap = QPixmap::fromImage(image);
  update();
  qApp->processEvents();
}

VideoStreamer::~VideoStreamer()
{
  delete ui;
}

void VideoStreamer::on_streamButton_clicked()
{
  _capture->changeState();

  if (_capture->isCapturing()) {
      ui->streamButton->setText("Stop");
    } else {
      ui->streamButton->setText("Start");
    }
}