I get a lot of mails to ask if I can also repair RAW image files. The answer is that I can’t. For some people I was able to Extract JPEG files from RAW image files though. I use a hex editor for that. Some times I do it for free (for a few files), normally I charge the ‘Low Res Preview’ extraction fee (see).
Update: first public release here. This functionality is now included in JPEG-Repair.
Utility to extract JPEG files from RAW camera files.
This week I had to do a huge load of .NEF (Nikon RAW files) so I decided it was time to put together a utility (JpegDigger) to process all .NEF files in a given directory.
I grabbed some more RAW image files from here: http://www.rawsamples.ch/index.php/en/canon and examined them with a hex editor. Turned out I had to use more than one signature to capture all JPEGs from all the different brand RAW files. A smaller more generic signature resulted in many false positives.
It currently works for .NEF, .CR2, .CRW, .ORF, .ARW, .SRW, .PEF, .DNG, .3FR, .RAF and .RW2 RAW camera images. If your format isn’t listed, feel free to sent me a intact RAW file shot with your camera. I will examine it and see if a JPEG is embedded. If there is I can add support for the RAW file.
Brute force JPEG extraction
A number of tools already exist to extract JPEG files from intact RAW files or to convert RAW images to JPEG (develop). For these to work the RAW image file must be intact. JpegDigger works differently and it is not RAW image file developer or RAW to JPEG converter.
Instead it opens the RAW file (corrupt or not) and carves out the JPEG data.
Many, but not all RAW camera files embed one or more (!) ‘preview’ JPEG files. The .NEF files I processed (most of them) resulted in a 1620 x 1080 and a 7360 x 4912 JPEG file.
Of course the RAW image data is always preferable, so this utility is meant as a last resort to at least get a picture.
I am now polishing JpegDigger and expect to upload it to this website later this week. Still deciding if this needs to be freeware or not, I’ve got bills to pay too, you know.