Method onTrigger

extensions/opencv/CaptureRTSPFrame.cpp:123–176

}

void CaptureRTSPFrame::onTrigger(const std::shared_ptr<core::ProcessContext> &context,
                                 const std::shared_ptr<core::ProcessSession> &session) {

  std::unique_lock<std::mutex> lock(mutex_, std::try_to_lock);
  if (!lock.owns_lock()) {
    logger_->log_info("Cannot process due to an unfinished onTrigger");
    context->yield();
    return;
  }

  try {
    video_capture_.open(rtsp_url_);
    video_backend_driver_ = video_capture_.getBackendName();
  } catch (const cv::Exception &e) {
    logger_->log_error("Unable to open RTSP stream: %s", e.what());
    context->yield();
    return;
  } catch (...) {
    logger_->log_error("Unable to open RTSP stream: unhandled exception");
    context->yield();
    return;
  }

  auto flow_file = session->create();
  cv::Mat frame;
  // retrieve a frame of your source
  if (video_capture_.read(frame)) {
    if (!frame.empty()) {
      CaptureRTSPFrameWriteCallback write_cb(frame, image_encoding_);

      auto t = std::time(nullptr);
      auto tm = *std::localtime(&t);

      std::ostringstream oss;
      oss << std::put_time(&tm, "%d-%m-%Y %H-%M-%S");
      auto filename = oss.str();
      filename.append(image_encoding_);

      session->putAttribute(flow_file, "filename", filename);
      session->putAttribute(flow_file, "video.backend.driver", video_backend_driver_);

      session->write(flow_file, &write_cb);
      session->transfer(flow_file, Success);
      logger_->log_info("A frame is captured");
    } else {
      logger_->log_error("Empty Mat frame received from capture");
      session->transfer(flow_file, Failure);
    }
  } else {
    logger_->log_error("Unable to read from capture handle on RTSP stream");
    session->transfer(flow_file, Failure);
  }

}

void CaptureRTSPFrame::notifyStop() {
}