Why does my iphone say my photos take up so much space?

I have only like 300 photos in my iphone and it still says that it takes up 4GB and its frustrating since i've already deleted over 700 photos and my phone still does indicate much change of my storage space. Could it be that there's some hidden location all my photos have been saved or something?

It may be that you have a duplicate album or you have your phone set to a setting where all of your pictures are taken in really high quality and that could be taking up extra space

There's no way thats taking 4 gig, maybe if you have a bunhc of videos.