How to recover data from corrupted RAW photos

By | December 1, 2021

Repairing corrupt RAW photos (CR2, NEF, ARF etc.)

There aren’t many solutions or even services available that actually and truly repair RAW photos produced by high-end digital cameras such as DSLRs from Canon, Sony and Nikon. Most software that claims this capability actually does nothing of the sort but in fact they simply extract JPEG data that’s embedded in such RAW files. My tool JPEG-Repair is also capable of doing this.

Universal Header Repair Tool is designed to diagnose and repair RAW photos in batch.

Again, I know of no tools that offer true RAW photo repair. As part of my photo repair service, I do frequently repair RAW photos but this is very much a manual process using a hex editor. It is labor intensive and therefor expensive. To address this I have invested some time in writing a tool that allows me to:

  • Research the damage in RAW photos
  • Design a solution
  • Execute the solution in batch on multiple files

I call it the Universal Header Repair Tool (U.H.R.T.) As a result I can repair RAW photos more often, quicker and cheaper. Main costs now are in diagnostics and designing the solution. If the actual repair can then be batched then this is only a fraction of the costs. If you need a quote for repair of your RAW photos you can use the Photo Repair Service page.

Some times even visual corruption in RAW files (example: Sony ARW file) can be repaired!

Extracting JPEGs from RAW photos

JPG-Repair Toolkit allows you to recover data from corrupted RAW photos (JPEG). RAW photos contain the raw, ‘undeveloped’ sensor data from high-end digital cameras such as DSLRs from Canon, Sony, Nikon, Konica, Olympus etc.. JPG-Repair Toolkit can process multiple RAW files in batch.

Commonly these RAW photos embed one or more JPEGs: a low resolution thumbnail, a medium resolution preview, and in many cases a full frame preview. Using JPG-Repair Toolkit you can extract the full frame preview. The latter is true even if resolution for the RAW photo was set to a lower value. There are tools available to extract this data from a RAW photo, but typically they parse intact files and refuse to work on corrupted files.

Other ‘repair’ software available only extracted either thumbnails or medium sized previews during my testing and as per customer’s comments (“I just purchased Stellar and all it does is save the thumbnail”). Following formats are currently supported:

Technically JPG-Repair Toolkit does not repair RAW files, it extracts JPEGs already embedded!

How to recover data from corrupted RAW photos using JPG-Repair Toolkit

Time needed: 1 minute, assuming you have downloaded JPG-Repair Toolkit.

Steps to extract JPEGs from corrupted RAW photos:

  1. Select a Repair mode > Pick Extract JPEG
  2. Browse to the folder containing the corrupted RAW file(s) and select files you want to extract embedded JPEGs from.
  3. Select a minimum resolution, > 3.0 (MP) to skip lower resolution thumbnails and medium sized previews.
  4. Click Repair.

Acknowledgements:

To determine signatures I examined RAW files taken from: http://www.rawsamples.ch/index.php/en/canon.
And also: https://www.wesaturate.com/.

 

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