I personally prefer safecopy. It can do a coarse read first, then try more reads on damaged sectors. If you have a spinning rust drive that you had to put in the freezer to get it to work, that lets you get most data out without wasting repeated effort on unreadable sectors. Also works great for CDs! Source: about 2 years ago

Never tried myself, but there are tools like ddrescue and safecopy that try to grab what they can. Source: about 2 years ago

Http://safecopy.sourceforge.net/ (there are almost certainly better sources than sourceforge, but I'd try to avoid any windows stuff that is wildly different). Source: almost 3 years ago

Then use something like http://safecopy.sourceforge.net/ or http://hddguru.com/software/HDD-Raw-Copy-Tool/ or ddrescue to try to get the rest if you need it. Source: about 3 years ago

Companies that can help are https://mp4repair.org/, https://fix.video/ and also disktuna.com (c'est moi). They'll probably ask for a reference file: a short video shot with same camera. Source: over 2 years ago

I can recommend the previously mentioned u/pcimage too, or u/magnificentstarfish in the Neherlands, who develops a picture carver application himself (http://disktuna.com). Source: over 2 years ago