Compilation arguments: a set of data structures which can be passed to control compilation process. More...

Classes
struct	cv::GCompileArg
	Represents an arbitrary compilation argument. More...

class	cv::gapi::GKernelPackage
	A container class for heterogeneous kernel implementation collections. More...

struct	cv::graph_dump_path
	Ask G-API to dump compiled graph in Graphviz format under the given file name. More...

Typedefs
using	cv::GCompileArgs = std::vector< GCompileArg >

using	cv::gapi::GLookupOrder = std::vector< GBackend >
	Priority list of backends to use during kernel resolution process. More...

Functions
template<typename... Ts>
GCompileArgs	cv::compile_args (Ts &&... args)

template<typename... KK>
GKernelPackage	cv::gapi::kernels ()
	Create a kernel package object containing kernels specified in variadic template argument. More...

GLookupOrder	cv::gapi::lookup_order (std::initializer_list< GBackend > &&list)
	Create a backend lookup order – priority list of backends to use during graph compilation process. More...

Detailed Description

Compilation arguments: a set of data structures which can be passed to control compilation process.

G-API comes with a number of graph compilation options which can be passed to cv::GComputation::apply() or cv::GComputation::compile(). Known compilation options are listed in this page, while extra backends may introduce their own compilation options (G-API transparently accepts everything which can be passed to cv::compile_args(), it depends on underlying backends if an option would be interpreted or not).

For example, if an example computation is executed like this:

cv::GComputation sobelEdge(cv::GIn(in), cv::GOut(out));

sobelEdge.apply(input, output);

Extra parameter specifying which kernels to compile with can be passed like this:

    cv::gapi::GKernelPackage kernels = cv::gapi::combine
        (cv::gapi::core::fluid::kernels(),
         cv::gapi::imgproc::fluid::kernels(),
         cv::unite_policy::KEEP);
    sobelEdge.apply(input, output, cv::compile_args(kernels));

Typedef Documentation

§ GCompileArgs

using cv::GCompileArgs = typedef std::vector<GCompileArg>

§ GLookupOrder

using cv::gapi::GLookupOrder = typedef std::vector<GBackend>

Priority list of backends to use during kernel resolution process.

Priority is descending – the first backend in the list has the top priority, and the last one has the lowest priority.

If there's multiple implementations available for a kernel at the moment of graph compilation, a kernel (and thus a backend) will be selected according to this order (if the parameter is passed).

Default order is not specified (and by default, only CPU(OpenCV) backend is involved in graph compilation).

Function Documentation

§ compile_args()

template<typename... Ts>

GCompileArgs cv::compile_args ( Ts &&... args )

Wraps a list of arguments (a parameter pack) into a vector of compilation arguments (cv::GCompileArg).

§ kernels()

template<typename... KK>

GKernelPackage cv::gapi::kernels ( )

Create a kernel package object containing kernels specified in variadic template argument.

In G-API, kernel implementations are types. Every backend has its own kernel API (like GAPI_OCV_KERNEL() and GAPI_FLUID_KERNEL()) but all of that APIs define a new type for each kernel implementation.

Use this function to pass kernel implementations (defined in either way) to the system. Example:

    cv::gapi::GKernelPackage pkg = cv::gapi::kernels
        < CustomAdd
        , CustomFilter2D
        , CustomRGB2YUV
        >();

Note that kernels() itself is a function returning object, not a type, so having () at the end is important – it must be a function call.

§ lookup_order()

GLookupOrder cv::gapi::lookup_order ( std::initializer_list< GBackend > && list )

inline

Create a backend lookup order – priority list of backends to use during graph compilation process.

See also: GLookupOrder, G-API Standard backends

Classes

Typedefs

Functions