Office Lens from the MS store is excellent for 'scanning ' music with your phone/tablet/PC and converting it to a pdf. ITt does all the image optimization and croping automatically. I think its available on ANdriod and IOS as well.
https://www.microsoft.com/de-de/store/p/...zdncrfj3t8
https://www.microsoft.com/de-de/store/p/...zdncrfj3t8