python图⽚截取斜四边形_opencv截取任意四边形区域的图像截取任意四边形区域的图像。
mask就是结果。
需要定义四边形区域，分别是 tl, tr, bl, br
std::map> generateBorders(const std::vector<:point> & vecPts)
{
std::map> borders;
cv::Point tl(vecPts[0]), tr(vecPts[1]), bl(vecPts[2]), br(vecPts[3]);
// tl to tr
double K = double(tl.y-tr.y) / (tl.x - tr.x);
for (int i = tl.x; i < tr.x; ++i)
borders[i].inrt(cvRound(-K*(tl.x - i) + tl.y));
苏教版英语
/
/ tr to br
if (tr.x != br.x)亚洲女神
{
K = double(tr.y - br.y) / (tr.x - br.x);
for (int i = tr.x; i < br.x; ++i)
borders[i].inrt(cvRound(-K*(tr.x - i) + tr.y));
}
// br to bl
K = double(br.y - bl.y) / (br.x - bl.x);
for (int i = bl.x; i < br.x; ++i)
borders[i].inrt(cvRound(-K*(br.x - i) + br.y));
红烧猪蹄怎么做
/学生会申请书格式
/ bl to tl
if (bl.x != tl.x)
{
K = double(bl.y - tl.y) / (bl.x - tl.x);
for (int i = tl.x; i < bl.x; ++i)
borders[i].inrt(cvRound(-K*(bl.x - i) + bl.y));
}
for (auto it = borders.begin(); it!=d(); ++it)
{
if ((*it).cond.size() == 2)
continue;
std::t newone = { *(*it).cond.begin(), *(--(*it).d())};
(*it).cond.swap(newone);
}
#ifdef DEBUG_CODE
cv::Mat disp = cv::imread("1111.PNG", CV_LOAD_IMAGE_COLOR);
for (auto it = borders.begin(); it != d(); ++it)
很字的笔顺{
cv::circle(disp, cv::Point((*it).first, *(*it).cond.begin()), 1, cv::Scalar(255, 255, 0), -1); cv::circle(disp, cv::Point((*it).first, *(--(*it).d())), 1, cv::Scalar(0, 255, 255), -1); }
户外睡袋
cv::circle(disp, tl, 2, cv::Scalar(0, 0, 255), -1);
cv::circle(disp, tr, 2, cv::Scalar(0, 0, 255), -1);
cv::circle(disp, bl, 2, cv::Scalar(0, 0, 255), -1);
cv::circle(disp, br, 2, cv::Scalar(0, 0, 255), -1);
#endif // DEBUG_CODE
return borders;
}
cv::Mat generateMask(const cv::Mat & src,
const std::vector<:point> & vecPts)
{
cv::Mat mask = cv::Mat::zeros(src.size(), CV_8UC1);
cv::Point tl(vecPts[0]), tr(vecPts[1]), bl(vecPts[2]), br(vecPts[3]);
有情后感std::map> borders = generateBorders(vecPts);
int minX = std::min(tl.x, bl.x),
maxX = std::max(tr.x, br.x),
minY = std::min(tl.y, tr.y),
maxY = std::max(bl.y, br.y);王力宏祖籍
uchar minZ = std::min(src.at(tl), src.at(tr));
minZ = std::min(minZ, src.at(bl));
minZ = std::min(minZ, src.at(br));
for (size_t j= minY; j
{
const uchar* pS = src.ptr(j);
uchar* pM = mask.ptr(j);
for (size_t i = minX; i < maxX; ++i)
{
// in the region.
if (*borders[i].begin() < j && j < *(++borders[i].begin())) {
pM[i] = pS[i];
}
}
}
return mask;
}
