how to crop image from detected rectangle.?

Question

Nimisha 2016-2-16

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/268444-how-to-crop-image-from-detected-rectangle

评论： bhagyashri kapre 2019-9-12

 clear all;clc
boxImage = imread('IMG.jpg');
boxImage = boxImage(:,:,3);
figure; imshow(boxImage);
title('Image of a Box');
sceneImage = imread('IMG1.jpg');
sceneImage = sceneImage(:,:,3);
figure; imshow(sceneImage);
title('Image of a Cluttered Scene');
boxPoints = detectSURFFeatures(boxImage);
scenePoints = detectSURFFeatures(sceneImage);
figure; imshow(boxImage);
title('100 Strongest Feature Points from Box Image');
hold on;
plot(boxPoints.selectStrongest(100));
figure; imshow(sceneImage);
title('300 Strongest Feature Points from Scene Image');
hold on;
plot(scenePoints.selectStrongest(300));
[boxFeatures, boxPoints] = extractFeatures(boxImage, boxPoints);
[sceneFeatures, scenePoints] = extractFeatures(sceneImage, scenePoints);
boxPairs = matchFeatures(boxFeatures, sceneFeatures);
matchedBoxPoints = boxPoints(boxPairs(:, 1), :);
matchedScenePoints = scenePoints(boxPairs(:, 2), :);
figure;
showMatchedFeatures(boxImage, sceneImage, matchedBoxPoints, ...
    matchedScenePoints, 'montage');
title('Putatively Matched Points (Including Outliers)');
[tform, inlierBoxPoints, inlierScenePoints] = ...
    estimateGeometricTransform(matchedBoxPoints, matchedScenePoints, 'affine');
figure;
showMatchedFeatures(boxImage, sceneImage, inlierBoxPoints, ...
    inlierScenePoints, 'montage');
title('Matched Points (Inliers Only)');
boxPolygon = [1, 1;...                           % top-left
        size(boxImage, 2), 1;...                 % top-right
        size(boxImage, 2), size(boxImage, 1);... % bottom-right
        1, size(boxImage, 1);...                 % bottom-left
        1, 1];                   % top-left again to close the polygon
    newBoxPolygon = transformPointsForward(tform, boxPolygon);
    figure; imshow(sceneImage);
hold on;
line(newBoxPolygon(:, 1), newBoxPolygon(:, 2), 'Color', 'y');
title('Detected Box');

After ruuning this code, i am able to detect features of one image into another and it draws a rectange at detected portion. Now i want to crop that detected portion and want to save.. How to crop it and save it.?