Licensing
...
Some of the HEVC algorithms may be protected by patents in some countries (read the FFmpeg Patent Mini-FAQ for more information). Most devices already include or will include hardware HEVC support, so we suggest to use it if patents are an issue.
http://bellard.org/bpg/
This will not save you from the HEVC Advance content fees, which are a percentage of your website's total revenue related to the images.
If so, almost sounds like the reason to use it on free websites, so paid for ones do not steal your images
Licensing
...
Some of the HEVC algorithms may be protected by patents in some countries (read the FFmpeg Patent Mini-FAQ for more information). Most devices already include or will include hardware HEVC support, so we suggest to use it if patents are an issue.
http://bellard.org/bpg/