Cannot access assets - unable to open image I'm on Craft 2.7.8 and cannot access some of my assets - getting 
Unable to open image ../html/assets/xxx.jpg error all the time. 

I've checked the owner, group and permissions dozen of times, currently everything set to root and 777. 

I can access the images when I go directly to that URL in a browser, but for some reasons I cannot access them in a template.

In the Craft Admin Panel I changed the Source type to Amazon S3 bucket but that didn't work too. I can see the access/secret keys are correct (can display available buckets) but getting the same error "403 - unable to open".

Double checked with Postman and confirmed the images are there - looks like it's a Craft's or the Imager plugin issue.

Any ideas, please?
I'm using html as the root of my website (instead of public) and running on Apache. 

Thanks
The solution to my problem was installing the ImageMagick package. 

Regarding the S3 bucket - Craft 2 doesn't support my region (Frankfurt) - read more here.