Tips:
Samsung backup and restore with Samsung Smart Switch
Samsung photo recovery
[b]Samsung video recovery[/b]

If you don’t have backup, you may need a third party software to recover your lost or deleted Samsung data. For Mac users, you can try Android Data Recovery Mac. For Windows users, you can try Samsung Data Recovery. Both of them offer you a simple and safe way to recover lost contacts, text messages, photos, videos, audio, WhatsApp messages, Viber messages and etc from Android phone internal memory and SD card.
Other Related Information:
Articles:
How to Retrieve Deleted Viber Messages/Chat History on Android Mac
Easy Way to Retrieve Deleted WhatsApp Messages on Android Mac
How to Transfer Samsung Galaxy S7 Photos/Videos to Computer
Videos:
How to retrieve deleted viber messages/ chat history on Samsung
https://youtu.be/A2DxgsZqeB8
How to Restore Deleted WhatsApp Chat history from Android Devices
https://youtu.be/zlXNXQnejpk