gaze::pipeline::SourceCapture Class Reference

Retrieves frames from a webcam or video source. More...

#include "gaze/pipeline_steps/source_capture.h"

Inheritance diagram for gaze::pipeline::SourceCapture:

Public Member Functions
void	process (util::Data &data) override
void	visualize (util::Data &data) override
Creating a source capture
	SourceCapture ()
Public Member Functions inherited from gaze::PipelineStep
	PipelineStep ()
std::string	get_name ()
virtual	~PipelineStep ()=default
Public Member Functions inherited from gaze::gui::Visualizeable< widget_type >
std::shared_ptr< dlib::drawable >	init (dlib::drawable_window &parent, int width, int height, std::string text="No visualization.") final
void	remove_widget () override
Public Member Functions inherited from gaze::gui::VisualizeableBase
virtual	~VisualizeableBase ()=default

Additional Inherited Members
Protected Attributes inherited from gaze::PipelineStep
int	number
std::string	name
Protected Attributes inherited from gaze::gui::Visualizeable< widget_type >
std::shared_ptr< widget_type >	widget

Detailed Description

Retrieves frames from a webcam or video source.

Should be used at the beginning of a Pipeline.

Definition at line 24 of file source_capture.h.

Constructor & Destructor Documentation

gaze::pipeline::SourceCapture::SourceCapture

(

)

Creates a cv::VideoCapture as the input source.

If the source specified in the yaml configuration is a string, it is considered as a path, otherwise the number will be parsed as a webcam address.

Definition at line 18 of file source_capture.cpp.

References cv::CAP_PROP_FPS, cv::CAP_PROP_FRAME_HEIGHT, cv::CAP_PROP_FRAME_WIDTH, gaze::util::get_config(), gaze::PipelineStep::name, gaze::PipelineStep::number, and cv::VideoCapture::set().

                             {
  YAML::Node config = util::get_config(this->number);
  this->name = config["name"] ?
    config["name"].as<std::string>() : "SourceCapture";

  std::string source = config["source"] ?
    config["source"].as<std::string>() : "0";

  bool is_webcam = true;
  try {
    int cam_source = std::stoi(source);
    this->video_capture = cv::VideoCapture(cam_source);
  } catch (const std::invalid_argument&) {
    is_webcam = false;
    this->video_capture = cv::VideoCapture(source);
  }

  if (is_webcam) {
    YAML::Node camera_config = util::get_config()["meta"]["camera"];
    this->video_capture.set(cv::CAP_PROP_FPS,
        camera_config["fps"] ? camera_config["fps"].as<double>() : 60.0);
    this->video_capture.set(cv::CAP_PROP_FRAME_WIDTH,
        camera_config["resolution"]["width"] ?
        camera_config["resolution"]["width"].as<double>() : 640.0);
    this->video_capture.set(cv::CAP_PROP_FRAME_HEIGHT,
        camera_config["resolution"]["height"] ?
        camera_config["resolution"]["height"].as<double>() : 360.0);
  }
}

Member Function Documentation

void gaze::pipeline::SourceCapture::process ( util::Data &  data )

overridevirtual

Reads a frame from the video source and stores it as the data's util::Data::souce_image.

Parameters

data	The data object to be updated.

Returns

via data the modified data object.

Implements gaze::PipelineStep.

Definition at line 52 of file source_capture.cpp.

References cv::CAP_PROP_POS_AVI_RATIO, cv::VideoCapture::get(), gaze::util::Data::image, cv::VideoCapture::read(), and gaze::util::Data::source_image.

                                          {
  if (static_cast<int>(this->video_capture.get(cv::CAP_PROP_POS_AVI_RATIO))
      == 1) {
    return;
  }
  bool received = this->video_capture.read(data.source_image);
  if (received) {
    this->last_frame = data.source_image;
  } else {
    data.source_image = this->last_frame;
  }
  dlib::assign_image(
     data.image,
     dlib::cv_image<dlib::bgr_pixel>(data.source_image));
}

void gaze::pipeline::SourceCapture::visualize ( util::Data &  data )

overridevirtual

Just assigns the data's raw camera image to the widget.

Parameters

data	the data object.

Implements gaze::gui::VisualizeableBase.

Definition at line 68 of file source_capture.cpp.

References gaze::util::Data::image, and gaze::gui::Visualizeable< widget_type >::widget.

                                            {
  this->widget->set_image(data.image);
}

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The documentation for this class was generated from the following files:

• include/gaze/pipeline_steps/source_capture.h
• src/gaze/pipeline_steps/source_capture.cpp