Photo in icloud are corrupted I have scanned a few photos back in Dec 2013. They were scanned by 'Image Capture' app and they were imported into icloud via Photo at least two years ago. 

Today when I browsed my photo on osx, I realised they are corrupted:



When I checked my iphone they are corrupted in the same way.

I want to know how can I find out the extent of damages to my photo collection. I have imported my entire family album and there are over 40000 photo and 2500 video. It is impossible to access them one by one by myself.
You need to contact Apple Support right away. Your iCloud account could be having functionality issues. They can put in a petition to the iCloud team so they can investigate your account.