opencv/samples/gpu/brox_optical_flow.cpp
Andrey Kamaev 2a6fb2867e Remove all using directives for STL namespace and members
Made all STL usages explicit to be able automatically find all usages of
particular class or function.
2013-02-25 15:04:17 +04:00

269 lines
7.5 KiB
C++

#include <iostream>
#include <iomanip>
#include <string>
#include <cctype>
#include "cvconfig.h"
#include "opencv2/core/core.hpp"
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/gpu/gpu.hpp"
using namespace std;
using namespace cv;
using namespace cv::gpu;
void getFlowField(const Mat& u, const Mat& v, Mat& flowField);
int main(int argc, const char* argv[])
{
try
{
const char* keys =
"{ h help | | print help message }"
"{ l left | | specify left image }"
"{ r right | | specify right image }"
"{ s scale | 0.8 | set pyramid scale factor }"
"{ a alpha | 0.197 | set alpha }"
"{ g gamma | 50.0 | set gamma }"
"{ i inner | 10 | set number of inner iterations }"
"{ o outer | 77 | set number of outer iterations }"
"{ si solver | 10 | set number of basic solver iterations }"
"{ t time_step | 0.1 | set frame interpolation time step }";
CommandLineParser cmd(argc, argv, keys);
if (cmd.has("help") || !cmd.check())
{
cmd.printMessage();
cmd.printErrors();
return 0;
}
string frame0Name = cmd.get<string>("left");
string frame1Name = cmd.get<string>("right");
float scale = cmd.get<float>("scale");
float alpha = cmd.get<float>("alpha");
float gamma = cmd.get<float>("gamma");
int inner_iterations = cmd.get<int>("inner");
int outer_iterations = cmd.get<int>("outer");
int solver_iterations = cmd.get<int>("solver");
float timeStep = cmd.get<float>("time_step");
if (frame0Name.empty() || frame1Name.empty())
{
cerr << "Missing input file names" << endl;
return -1;
}
Mat frame0Color = imread(frame0Name);
Mat frame1Color = imread(frame1Name);
if (frame0Color.empty() || frame1Color.empty())
{
cout << "Can't load input images" << endl;
return -1;
}
cv::gpu::printShortCudaDeviceInfo(cv::gpu::getDevice());
cout << "OpenCV / NVIDIA Computer Vision" << endl;
cout << "Optical Flow Demo: Frame Interpolation" << endl;
cout << "=========================================" << endl;
namedWindow("Forward flow");
namedWindow("Backward flow");
namedWindow("Interpolated frame");
cout << "Press:" << endl;
cout << "\tESC to quit" << endl;
cout << "\t'a' to move to the previous frame" << endl;
cout << "\t's' to move to the next frame\n" << endl;
frame0Color.convertTo(frame0Color, CV_32F, 1.0 / 255.0);
frame1Color.convertTo(frame1Color, CV_32F, 1.0 / 255.0);
Mat frame0Gray, frame1Gray;
cvtColor(frame0Color, frame0Gray, COLOR_BGR2GRAY);
cvtColor(frame1Color, frame1Gray, COLOR_BGR2GRAY);
GpuMat d_frame0(frame0Gray);
GpuMat d_frame1(frame1Gray);
cout << "Estimating optical flow" << endl;
BroxOpticalFlow d_flow(alpha, gamma, scale, inner_iterations, outer_iterations, solver_iterations);
cout << "\tForward..." << endl;
GpuMat d_fu, d_fv;
d_flow(d_frame0, d_frame1, d_fu, d_fv);
Mat flowFieldForward;
getFlowField(Mat(d_fu), Mat(d_fv), flowFieldForward);
cout << "\tBackward..." << endl;
GpuMat d_bu, d_bv;
d_flow(d_frame1, d_frame0, d_bu, d_bv);
Mat flowFieldBackward;
getFlowField(Mat(d_bu), Mat(d_bv), flowFieldBackward);
cout << "Interpolating..." << endl;
// first frame color components
GpuMat d_b, d_g, d_r;
// second frame color components
GpuMat d_bt, d_gt, d_rt;
// prepare color components on host and copy them to device memory
Mat channels[3];
cv::split(frame0Color, channels);
d_b.upload(channels[0]);
d_g.upload(channels[1]);
d_r.upload(channels[2]);
cv::split(frame1Color, channels);
d_bt.upload(channels[0]);
d_gt.upload(channels[1]);
d_rt.upload(channels[2]);
// temporary buffer
GpuMat d_buf;
// intermediate frame color components (GPU memory)
GpuMat d_rNew, d_gNew, d_bNew;
GpuMat d_newFrame;
vector<Mat> frames;
frames.reserve(static_cast<int>(1.0f / timeStep) + 2);
frames.push_back(frame0Color);
// compute interpolated frames
for (float timePos = timeStep; timePos < 1.0f; timePos += timeStep)
{
// interpolate blue channel
interpolateFrames(d_b, d_bt, d_fu, d_fv, d_bu, d_bv, timePos, d_bNew, d_buf);
// interpolate green channel
interpolateFrames(d_g, d_gt, d_fu, d_fv, d_bu, d_bv, timePos, d_gNew, d_buf);
// interpolate red channel
interpolateFrames(d_r, d_rt, d_fu, d_fv, d_bu, d_bv, timePos, d_rNew, d_buf);
GpuMat channels3[] = {d_bNew, d_gNew, d_rNew};
merge(channels3, 3, d_newFrame);
frames.push_back(Mat(d_newFrame));
cout << setprecision(4) << timePos * 100.0f << "%\r";
}
frames.push_back(frame1Color);
cout << setw(5) << "100%" << endl;
cout << "Done" << endl;
imshow("Forward flow", flowFieldForward);
imshow("Backward flow", flowFieldBackward);
int currentFrame = 0;
imshow("Interpolated frame", frames[currentFrame]);
for(;;)
{
int key = toupper(waitKey(10) & 0xff);
switch (key)
{
case 27:
return 0;
case 'A':
if (currentFrame > 0)
--currentFrame;
imshow("Interpolated frame", frames[currentFrame]);
break;
case 'S':
if (currentFrame < static_cast<int>(frames.size()) - 1)
++currentFrame;
imshow("Interpolated frame", frames[currentFrame]);
break;
}
}
}
catch (const exception& ex)
{
cerr << ex.what() << endl;
return -1;
}
catch (...)
{
cerr << "Unknow error" << endl;
return -1;
}
}
template <typename T> inline T clamp (T x, T a, T b)
{
return ((x) > (a) ? ((x) < (b) ? (x) : (b)) : (a));
}
template <typename T> inline T mapValue(T x, T a, T b, T c, T d)
{
x = clamp(x, a, b);
return c + (d - c) * (x - a) / (b - a);
}
void getFlowField(const Mat& u, const Mat& v, Mat& flowField)
{
float maxDisplacement = 1.0f;
for (int i = 0; i < u.rows; ++i)
{
const float* ptr_u = u.ptr<float>(i);
const float* ptr_v = v.ptr<float>(i);
for (int j = 0; j < u.cols; ++j)
{
float d = max(fabsf(ptr_u[j]), fabsf(ptr_v[j]));
if (d > maxDisplacement)
maxDisplacement = d;
}
}
flowField.create(u.size(), CV_8UC4);
for (int i = 0; i < flowField.rows; ++i)
{
const float* ptr_u = u.ptr<float>(i);
const float* ptr_v = v.ptr<float>(i);
Vec4b* row = flowField.ptr<Vec4b>(i);
for (int j = 0; j < flowField.cols; ++j)
{
row[j][0] = 0;
row[j][1] = static_cast<unsigned char> (mapValue (-ptr_v[j], -maxDisplacement, maxDisplacement, 0.0f, 255.0f));
row[j][2] = static_cast<unsigned char> (mapValue ( ptr_u[j], -maxDisplacement, maxDisplacement, 0.0f, 255.0f));
row[j][3] = 255;
}
}
}