Swallows, Or House Martins ?

All I know is they make a lovely sound with their "vibrating  cry" for more food  and the parents oblige by darting hither and thither collecting . Lots of these birds nest around here as the architecture is ideal .I've a crick in the neck from leaning on railings whilst looking up filming but it was well worth it .The link is to a very short video 40 seconds with a returning parent .This made my day, Not easy to catch on film .
Back To The Nest, A Busy Life