opencv倾斜校正 java,opencv图像倾斜校正和切边

#include

#include

#include

using namespace std;

using namespace cv;

const char input[] = "Input image";

const char output[] = "Output image";

void fileCutLine(int, void*);//对图片边缘切取

void rotateImage(int,void*);//对于图片进行旋转矫正

Mat src, dst,rotateSrc;

int main(void) {

src = imread("..\\cutLineTest.jpg");

rotateSrc = imread("..\\rotateTestImage.jpg");

if (src.empty()||rotateSrc.empty()) {

cout << "Loading image failed!" << endl;

return -1;

}

pyrDown(rotateSrc, rotateSrc);

namedWindow(input, WINDOW_AUTOSIZE);

namedWindow(output, WINDOW_AUTOSIZE);

int thresh = 134;

//createTrackbar("Control threshold", output, &thresh, 255, fileCutLine);

//fileCutLine(thresh, 0);

createTrackbar("Rotate fix", output, &thresh, 255, rotateImage);

rotateImage(thresh, 0);

//imshow(input, src);

imshow(input, rotateSrc);

waitKey(0);

return 0;

}

void fileCutLine(int thresh, void*) {

Mat gray;

Mat border;

Mat kernel = Mat(Size(3, 3), CV_8UC1);

cvtColor(src, gray, COLOR_BGR2GRAY);

GaussianBlur(gray, gray, Size(7, 7), 0);

//高斯模糊降噪

Canny(gray, border, thresh, 2 * thresh);

//通过开操作将黑色边缘上的水映文字去掉

morphologyEx(border, border, MORPH_OPEN, kernel);

vector> contours;

vector hierarchy;

findContours(border, contours,hierarchy, RETR_TREE, CHAIN_APPROX_SIMPLE,Point(0,0));

Rect mask;//最后获得的正确范围的遮罩

//Mat temp = Mat::zeros(src.size(), CV_8UC3);

//临时图像承载,用于观察边框

for (int i = 0; i < contours.size(); i++){

RotatedRect rect = minAreaRect(contours[i]);

Point2f corner[4];

//设置图片尺度条件，进行边缘矩形筛选

if ((rect.size.width > src.cols*0.75) && rect.size.height>src.rows*0.75) {

rect.points(corner);

//cout << "************************" << endl;

line(border, corner[0], corner[1], Scalar(0, 0, 255),2);

line(border, corner[1], corner[2], Scalar(0, 0, 255),2);

line(border, corner[3], corner[2], Scalar(0, 0, 255),2);

line(border, corner[3], corner[0], Scalar(0, 0, 255),2);

mask = rect.boundingRect();//返回包含旋转矩形的矩形

}

}

cout << mask.width << ‘ ‘ << mask.height << endl;

cout << src.cols << ‘ ‘ << src.rows << endl;

//imshow("temp", temp);

dst = src(mask);//比较好用

imshow(output, border);

if (!dst.empty()) {

imshow("Result", dst);

}

}

//如果图片是倾斜

void rotateImage(int thresh,void*) {

//Mat gray;

Mat border;

Mat kernel = Mat(Size(3, 3), CV_8UC1);

//cvtColor(rotateSrc, gray, COLOR_BGR2GRAY);

Canny(rotateSrc, border, thresh, 2 * thresh);

//通过开操作将黑色边缘上的水映文字去掉

//morphologyEx(border, border, MORPH_OPEN, kernel);

vector> contours;

vector hierarchy;

findContours(border, contours, hierarchy, RETR_EXTERNAL, CHAIN_APPROX_SIMPLE, Point(0, 0));

double angle = 0;//需要记录角度

Point2f center=Point2f(rotateSrc.rows/2,rotateSrc.cols/2);

Size fixSize;

Rect mask;

Mat temp = Mat(rotateSrc.size(),CV_8UC3);

for (int i = 0; i < contours.size(); i++){

RotatedRect rect = minAreaRect(contours[i]);

//center = rect.center;

Point2f corner[4];

rect.points(corner);

for (int j = 0; j < 4; j++){

line(temp, corner[j], corner[(j + 1) % 4], Scalar(255,255,255), 2);

}

if (rect.angle != 0) {

angle = rect.angle;

cout << "Angle:" << angle << endl;

}

}

Mat martix = getRotationMatrix2D(center, angle, 1);//得到仿射矩阵

warpAffine(rotateSrc, dst, martix, rotateSrc.size());

imshow("result", dst);

imshow(output,border);

}

在调整阈值时加了traceBar,调的时候方便一些。

结果如下(图是百度上随便找的)：