OpenCV  4.7.0-dev
Open Source Computer Vision
Public Member Functions | List of all members
cv::GFrame Class Reference

GFrame class represents an image or media frame in the graph. More...

#include <opencv2/gapi/gframe.hpp>

Public Member Functions

GAPI_WRAP GFrame ()
 Constructs an empty GFrame. More...
 

Detailed Description

GFrame class represents an image or media frame in the graph.

GFrame doesn't store any data itself, instead it describes a functional relationship between operations consuming and producing GFrame objects.

GFrame is introduced to handle various media formats (e.g., NV12 or I420) under the same type. Various image formats may differ in the number of planes (e.g. two for NV12, three for I420) and the pixel layout inside. GFrame type allows to handle these media formats in the graph uniformly – the graph structure will not change if the media format changes, e.g. a different camera or decoder is used with the same graph. G-API provides a number of operations which operate directly on GFrame, like infer<>() or renderFrame(); these operations are expected to handle different media formats inside. There is also a number of accessor operations like BGR(), Y(), UV() – these operations provide access to frame's data in the familiar cv::GMat form, which can be used with the majority of the existing G-API operations. These accessor functions may perform color space conversion on the fly if the image format of the GFrame they are applied to differs from the operation's semantic (e.g. the BGR() accessor is called on an NV12 image frame).

GFrame is a virtual counterpart of cv::MediaFrame.

See also
cv::MediaFrame, cv::GFrameDesc, BGR(), Y(), UV(), infer<>().

Constructor & Destructor Documentation

◆ GFrame()

GAPI_WRAP cv::GFrame::GFrame ( )

Constructs an empty GFrame.

Normally, empty G-API data objects denote a starting point of the graph. When an empty GFrame is assigned to a result of some operation, it obtains a functional link to this operation (and is not empty anymore).


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