科研必备之图像局部区域放大——画中画形式

在撰写图像处理领域相关的论文中通常需要将图片的某个小块进行放大，以便论文审稿者看到图像清晰的细节信息，本文主要使用matlab和QT（需要搭建opencv）来实现此种效果。

Matlab版本

function [ dest ] = draw_rect(src, startPosition, rectSize, lineSize, color)

[start_y, start_x] = deal(startPosition(1),startPosition(2));		% start position
[rect_size_w, rect_size_h] = deal(rectSize(1),rectSize(2));			% Rect Size

[width, height, channel] = size(src);
if channel==1
    dest(:, : ,1) = src;
    dest(:, : ,2) = src;
    dest(:, : ,3) = src;
else
    dest = src;
end

for channel_i = 1 : 3              
    for line_i = 1 : lineSize		% expand inside
	gain = line_i-1;
         dest(start_y+gain, (start_x+gain):(start_x+rect_size_w-gain),  channel_i ) =  color(channel_i);				%above
         dest(start_y+rect_size_h-gain,  (start_x+gain):(start_x+rect_size_w-gain), channel_i ) =  color(channel_i);	%bottom
         dest((start_y+gain):(start_y+rect_size_h-gain),  start_x+gain, channel_i ) =  color(channel_i);				%left
         dest((start_y+gain):(start_y+rect_size_h-gain),  start_x+rect_size_w-gain, channel_i ) =  color(channel_i);	%right
    end    
end 

QT版本（含界面）

void MainWindow::on_pushButton_2_clicked()
{
    int start_h = 220, start_w = 180;
    int rectSize = 50, scaleSize=3;
    Rect rect1 = Rect(start_h, start_w, rectSize, rectSize);        // specific rect
    Mat srcImage = imread("/home/mark/Sofeware/Qt/Qt_Project/QtApplication2/QT_DrawRect/lena.png");
    Mat imageRect = srcImage;
    cvtColor(imageRect, imageRect, CV_BGR2RGB);     // convert the BGR image to RGB
    Mat image_ROI = imageRect(rect1);    // define the ROI area and magnification ROI area
    Mat image_scaleROI;
    cv::resize(image_ROI, image_scaleROI, Size(scaleSize*rectSize, scaleSize*rectSize));
    Rect rect2 = Rect(imageRect.rows-image_scaleROI.rows, imageRect.cols-image_scaleROI.cols,  // magnification rect
                      image_scaleROI.rows, image_scaleROI.cols);
    image_scaleROI.copyTo(imageRect(rect2));        // cover the scaled ROI area
    rectangle(imageRect, rect1, cvScalar(255,0,0),2);  // draw two rect
    rectangle(imageRect, rect2, cvScalar(255,0,0),2);
    QImage image((const uchar*)imageRect.data, imageRect.cols, imageRect.rows,       // show image in Qlabel
                     imageRect.cols*imageRect.channels(), QImage::Format_RGB888);
    QImage showImage = image.scaled(ui->label->size(), Qt::IgnoreAspectRatio, Qt::SmoothTransformation);
    ui->label->setPixmap(QPixmap::fromImage(showImage));
    cvtColor(imageRect, imageRect, CV_RGB2BGR);
    imwrite("/home/mark/Sofeware/Qt/Qt_Project/QtApplication2/QT_DrawRect/output.png", imageRect);
}

最终应用两种方法得到的测试结果为：

完整的代码工程文件请前往github下载
https://github.com/RussellEven/Draw_Rect

转载须知：https://blog.csdn.net/weixin_39444746/article/details/88763550