Brian de Palma has forgotten more film history than I'll ever know in my entire life. (This is an American idiom that means a person who knows so much about a subject that they can afford to forget large parts of it and still be considered an expert.) I kind of see him as collage artist, not a thief. He's like the person who cuts out photos from magazines and then pastes them into an original picture that looks totally different from what the photos were meant to depict. In that way, he is better than Tarantino who is just kind of lazy and thinks that audiences won't recognize all the stuff he's ripping off (we do notice!). I need to watch Blow-Up and Blow-Out back-to-back again to answer your question. It's been a long time since seeing both.

The main problem with De Palma is that he gets so caught up in his technical proficiency (technically he's the equal of Kubrick or Hitchcock or Ridley Scott etc.) that he often forgets about scripts, acting, telling a story. He's made a lot of brilliant films and a lot of dogs, which has hurt his reputation. Where as top-tier directors like Kubrick etc. haven't made a lot of dogs. I kinda feel bad about where De Palma's career has ended up in his later years.