Detailed Explanation of RoI Pooling vs RoI Align vs RoI Warping

These feature extraction methods help you save information in your images!

In the last article, we went through the steps of building an object detector using Mask R-CNN which is able to output a mask over the detected object pixel by pixel. One of the steps in Mask R-CNN different from one in Faster R-CNN is the feature extraction method after the image is passed through a convolutional net. This step is called RoI Pooling in Faster R-CNN and RoI Align in Mask R-CNN.