how can i grow a region with connected compoent in other image?

hi i have 2 same images one of them is the mask and binary image the other one is the labeld image that each connected component has a label. i want to add all pixels in each connected component to first image if the mentioned connected compoenent has for example 30% participation with first image and growing the first imge that cover that connected component. how can i do this? supposing that the lable in second image are from 1 to 321