opencv/modules/gapi/samples/kernel_api_snippets.cpp
Dmitry Matveev dbed39a931 Merge pull request #12857 from dmatveev:hld
* G-API Documentation: first submission

This PR introduces a number of new OpenCV documentation chapters for
Graph API module.

In particular, the following topics are covered:
- Introduction & background information;
- High-level design overview;
- Kernel API;
- Pipeline example.

All changes are done in Markdown files, no headers, etc modified.

Doxygen references for main API classes will be added later.

Also, a tutorial will be introduced soon (in the common Tutorials place)

* G-API Documentation - fix warnings & trailing whitespaces

* G-API Documentation: address review issues

* G-API Documentation: export code snippets to compileable files

* gapi: move documentation samples
2018-10-24 07:47:56 +03:00

158 lines
4.7 KiB
C++

// [filter2d_api]
#include <opencv2/gapi.hpp>
G_TYPED_KERNEL(GFilter2D,
<cv::GMat(cv::GMat,int,cv::Mat,cv::Point,double,int,cv::Scalar)>,
"org.opencv.imgproc.filters.filter2D")
{
static cv::GMatDesc // outMeta's return value type
outMeta(cv::GMatDesc in , // descriptor of input GMat
int ddepth , // depth parameter
cv::Mat /* coeffs */, // (unused)
cv::Point /* anchor */, // (unused)
double /* scale */, // (unused)
int /* border */, // (unused)
cv::Scalar /* bvalue */ ) // (unused)
{
return in.withDepth(ddepth);
}
};
// [filter2d_api]
cv::GMat filter2D(cv::GMat ,
int ,
cv::Mat ,
cv::Point ,
double ,
int ,
cv::Scalar);
// [filter2d_wrap]
cv::GMat filter2D(cv::GMat in,
int ddepth,
cv::Mat k,
cv::Point anchor = cv::Point(-1,-1),
double scale = 0.,
int border = cv::BORDER_DEFAULT,
cv::Scalar bval = cv::Scalar(0))
{
return GFilter2D::on(in, ddepth, k, anchor, scale, border, bval);
}
// [filter2d_wrap]
// [compound]
#include <opencv2/gapi/gcompoundkernel.hpp> // GAPI_COMPOUND_KERNEL()
using PointArray2f = cv::GArray<cv::Point2f>;
G_TYPED_KERNEL(HarrisCorners,
<PointArray2f(cv::GMat,int,double,double,int,double)>,
"org.opencv.imgproc.harris_corner")
{
static cv::GArrayDesc outMeta(const cv::GMatDesc &,
int,
double,
double,
int,
double)
{
// No special metadata for arrays in G-API (yet)
return cv::empty_array_desc();
}
};
// Define Fluid-backend-local kernels which form GoodFeatures
G_TYPED_KERNEL(HarrisResponse,
<cv::GMat(cv::GMat,double,int,double)>,
"org.opencv.fluid.harris_response")
{
static cv::GMatDesc outMeta(const cv::GMatDesc &in,
double,
int,
double)
{
return in.withType(CV_32F, 1);
}
};
G_TYPED_KERNEL(ArrayNMS,
<PointArray2f(cv::GMat,int,double)>,
"org.opencv.cpu.nms_array")
{
static cv::GArrayDesc outMeta(const cv::GMatDesc &,
int,
double)
{
return cv::empty_array_desc();
}
};
GAPI_COMPOUND_KERNEL(GFluidHarrisCorners, HarrisCorners)
{
static PointArray2f
expand(cv::GMat in,
int maxCorners,
double quality,
double minDist,
int blockSize,
double k)
{
cv::GMat response = HarrisResponse::on(in, quality, blockSize, k);
return ArrayNMS::on(response, maxCorners, minDist);
}
};
// Then implement HarrisResponse as Fluid kernel and NMSresponse
// as a generic (OpenCV) kernel
// [compound]
// [filter2d_ocv]
#include <opencv2/gapi/cpu/gcpukernel.hpp> // GAPI_OCV_KERNEL()
#include <opencv2/imgproc.hpp> // cv::filter2D()
GAPI_OCV_KERNEL(GCPUFilter2D, GFilter2D)
{
static void
run(const cv::Mat &in, // in - derived from GMat
const int ddepth, // opaque (passed as-is)
const cv::Mat &k, // opaque (passed as-is)
const cv::Point &anchor, // opaque (passed as-is)
const double delta, // opaque (passed as-is)
const int border, // opaque (passed as-is)
const cv::Scalar &, // opaque (passed as-is)
cv::Mat &out) // out - derived from GMat (retval)
{
cv::filter2D(in, out, ddepth, k, anchor, delta, border);
}
};
// [filter2d_ocv]
int main(int, char *[])
{
std::cout << "This sample is non-complete. It is used as code snippents in documentation." << std::endl;
cv::Mat conv_kernel_mat;
{
// [filter2d_on]
cv::GMat in;
cv::GMat out = GFilter2D::on(/* GMat */ in,
/* int */ -1,
/* Mat */ conv_kernel_mat,
/* Point */ cv::Point(-1,-1),
/* double */ 0.,
/* int */ cv::BORDER_DEFAULT,
/* Scalar */ cv::Scalar(0));
// [filter2d_on]
}
{
// [filter2d_wrap_call]
cv::GMat in;
cv::GMat out = filter2D(in, -1, conv_kernel_mat);
// [filter2d_wrap_call]
}
return 0;
}