3 ms·
Still, as a non-programmer, if everything is so "easy" isn't it surprising that there are very few actually working (free/low cost) JPEG recovery/repair program
by jaclaz 5y ago
Still, as a non-programmer, if everything is so "easy" isn't it surprising that there are very few actually working (free/low cost) JPEG recovery/repair programs?
A very minor corruption in the file and poof you can retrieve nothing.
Many years ago there was a single program[1] that could, in a very small subset of cases, "fix" corrupted JPEG files (manually/inteactively), now (AFAIK) there is almost only [2] and [3] and this (service) [4] that actually produce (in some cases) good results.
In my (admitted) ignorance on the matter, I would have expected that with progresses like increased computer power, AI, deep fakes or whatever the problem by now was - if not solved - at least solved in a number of subset of cases.
[1] https://directory.s2services.com/jpg-bmp.htm https://directory.s2services.com/jpg-bmp.htm
[2] https://www.jpegmedic.com/tools/jpegmedic/ https://www.jpegmedic.com/tools/jpegmedic/ https://www.jpegmedic.com/tools/ https://www.jpegmedic.com/tools/
[3] https://www.hketech.com/ https://www.hketech.com/
[4] https://www.disktuna.com/ https://www.disktuna.com/
- kevmo314 5y agoI've never run across only a corrupted jpeg file, only something like entire fs corruption. So as someone who works in this space it's not so surprising because while I could probably write one it's not a problem I've ever thought of solving.
- jaclaz 5y agoWell, you are lucky. It is actually quite common to find partial/corrupted images. Typically an image will have a grey band/area or it will be "shifted" in some parts, some examples are here: https://www.jpegmedic.com/tools/jpegmedic/ https://www.jpegmedic.com/tools/jpegmedic/ Even checking if a file or an extent on disk is actually an image is not as easy as it seems (JFYI): https://www.forensicfocus.com/forums/mobile-forensics/jpeg-carving-identifying-recovering/ https://www.forensicfocus.com/forums/mobile-forensics/jpeg-c...
- mistercow 5y agoThis is just inherent to compression. The whole idea is to represent many bytes of data with fewer bytes. That means that the bytes you have each tend to count for a lot. So a small corruption has a huge effect. To solve this, the format itself needs to incorporate error correction. There are various ways to do that with different trade-offs, but all of them will hurt your compression ratio, because the only way to correct errors is to have some kind of redundancy, and removing redundancy is precisely what compression is about.
- Kletiomdm 5y agoThere are plenty of people who don't even do backups for there images. I believe that cloud storage and autosync fixed the issue of currupted images for most normal users.