JPEG Photo Repair

[lcoughey]

Although I haven't had a lot of success with this program, I can see how it could be useful in the right circumstance.

http://anderspedersen.net/jpegrepair/

As it is a manual repair process, it is not one that I recommend for those who have a huge amount of photos to repair. But, if it is just a few, it might be worth it. The program is free.

[Munawar84]

Can you give me suggestion when I need more.

[lcoughey]

I think maybe it needs an ypdate because when I tried it on a jpeg flie it said it doesn't recognize the file type lol.

I assume that you read the whole page on their site and saw the known error messages, one of which was:

I get an error: "Cannot load file. JPEG type not supported"

This means that the JPEG file uses progressive encoding (or another rare encoding format, but progressive is most likely). I do not plan to add support for progressive JPEG files. The reason for this is that while it would be rather simple to implement, it would incredible hard to use an require advanced knowledge of how data are stored in progressive JPEG files.

[Joep]

The tool is too clumsy, but interesting.

I created 3 tools that I use for JPEG repair:

- A checker that walks the chain of JPEG markers. Sort of like a chkdsk for JPEGs.
- An editor: like a hex editor but after each byte I modify I can re-render the JPEG so I can immediately see the result. I can also step through rendering and pinpoint the exact byte where corruption is introduced. I can then remove, add or modify the byte.
- An inpaint tool to fill in areas I deleted from the image stream by using the surrounding data.

This is an animated GIF of a recent project that shows the different stages of repair.

1. > 2, is after I fixed 'structural' damage (invalid markers taken out of the chain). As you can see all of a sudden data becomes visible.
3 + 4, I edit the image data
5, is after 'inpainting'.



- Joep

[lcoughey]

Very cool Joep How long is the average process to repair a single file? My main issue with JPEG photo repair is that sometimes a client has hundreds of damaged files, usually because of bad sectors.

[Joep]

Hi Luke,

Yes, that's the thing. Even a single bad sector I haven't been able to automate yet, it always requires me viewing the image and adjusting. But a single bad sector should be possible in under 5 minutes? Yeah, editing image stream and then inpainting tiny damaged areas, should be possible.

The one in the GIF was a mess. Viewers would only render half the image and the repair tool you mention at the start of the thread too. I can't really recall how long it took me as I modified my code in between as well. Running into all kinds of stuff I never ran into yet. Real 'production' time was probably at least an hour. So when you'd need to charge real labor cost it would be an expensive picture.

Do you run into this kind of stuff often? Do you offer customers you fix their JPGs? Want me to do it

[lcoughey]

We have recovery projects every day that have some damaged photos. In most cases, the clients are satisfied with the 99.99% of their files, as most are either duplicates or taken within seconds of each other. So, a missing photo is not really missed. So, don't be surprised if I do refer someone your way.

[Joep]

Do or don't? Be surprised ...

[Jared]

I've actually gotten pretty fast at repairing jpgs with bad sectors. I'd say I can repair a file with 3 or 4 bad sectors in around 5-6 minutes total. I've been offering this service for a while now: https://www.data-medics.com/jpeg-jpg-re ... -recovery/

[Joep]

Yeah 3 or 4 bad sectors, that should be possible in 5 - 10 minutes. Do you see lot of these cases? Do customers actually ask for it? Like Luke says, ppl nowadays keep just taking pics. So if one is corrupt but the rest of the very similar pics is okay they're probably not bothered by losing one?

The one in the GIF was sent to me by someone who already had been fixing some with Jpeg Repair Shop. The ones he sent me simply choked that tool. I was able to open one in Jpeg repair shop but it only showed half the image and the lower part simply showed no data that could be edited.

The images were somehow corrupted somewhere between shooting them and transferring them to a PC.

BTW, also a tool that's free for repairing similar damage but even clumsier to use can be found here: http://directory.s2services.com/jpg-bmp.htm.