Sound will be reflected, and the whole sound will be reflected. Both can be done. As long as the software can make small videos, it can make small videos of such advertisements. There is no difference. So you can actually go to the App Store to find software that can make small videos, because there are too many and too complete softwares in it, and they are all easy to find. If you find it, you can download it with confidence, because the software inside is safe.