I have large set of CT images containing lung regions. But I don't have corrosponding pixel labelled images. So how I could do semantic segmentation using DL in matlab. Like a test program I created 6 pixel labelled images using image Labeler. But it's not practical. I have thousands of such images. Could someone help me with a solution?
If you have the bounding boxes then you can use MaskRCNN and it will be able to give you those segmentations.
If you don't, look at unsupervised segmentation. Also, you need something as an output if you want to try out supervised learning.