Files
opencv_contrib/modules/wechat_qrcode/src/detector/align.cpp
2022-05-06 02:00:27 +08:00

67 lines
2.2 KiB
C++

// This file is part of OpenCV project.
// It is subject to the license terms in the LICENSE file found in the top-level directory
// of this distribution and at http://opencv.org/license.html.
//
// Tencent is pleased to support the open source community by making WeChat QRCode available.
// Copyright (C) 2020 THL A29 Limited, a Tencent company. All rights reserved.
#include "../precomp.hpp"
#include "align.hpp"
using std::max;
using std::min;
namespace cv {
namespace wechat_qrcode {
Align::Align() { rotate90_ = false; }
Mat Align::calcWarpMatrix(const Mat src, const Mat dst) {
M_ = getPerspectiveTransform(src, dst);
M_inv_ = M_.inv();
return M_;
}
vector<Point2f> Align::warpBack(const vector<Point2f> &dst_pts) {
vector<Point2f> src_pts;
for (size_t j = 0; j < dst_pts.size(); j++) {
auto src_x = (rotate90_ ? dst_pts[j].y : dst_pts[j].x) + crop_x_;
auto src_y = (rotate90_ ? dst_pts[j].x : dst_pts[j].y) + crop_y_;
src_pts.push_back(Point2f(src_x, src_y));
}
return src_pts;
}
Mat Align::crop(const Mat &inputImg, const int width, const int height) {
Mat warp_dst = Mat::zeros(height, width, inputImg.type());
warpPerspective(inputImg, warp_dst, M_, warp_dst.size(), INTER_LINEAR, BORDER_CONSTANT, 255);
return warp_dst;
}
Mat Align::crop(const Mat &inputImg, const Mat &srcPts, const float paddingW, const float paddingH,
const int minPadding) {
int x0 = srcPts.at<float>(0, 0);
int y0 = srcPts.at<float>(0, 1);
int x2 = srcPts.at<float>(2, 0);
int y2 = srcPts.at<float>(2, 1);
int width = x2 - x0 + 1;
int height = y2 - y0 + 1;
int padx = max(paddingW * width, static_cast<float>(minPadding));
int pady = max(paddingH * height, static_cast<float>(minPadding));
crop_x_ = max(x0 - padx, 0);
crop_y_ = max(y0 - pady, 0);
int end_x = min(x2 + padx, inputImg.cols - 1);
int end_y = min(y2 + pady, inputImg.rows - 1);
Rect crop_roi(crop_x_, crop_y_, end_x - crop_x_ + 1, end_y - crop_y_ + 1);
Mat dst = inputImg(crop_roi).clone();
if (rotate90_) dst = dst.t(); // transpose
return dst;
}
} // namespace wechat_qrcode
} // namespace cv