JpegDigger
Posted: Tue Jul 30, 2019 5:38 pm
Sow ..
I know JpegDigger has been discussed here so: JpegDigger formerly was for grabbing JPEGs from RAW photos however I discontinued it at some point as this was a feature transferred JPEG-Repair.
Last couple of months I ran into the situation where I needed JPEGs from memory cards and JPEG Recovery LAB takes such a darn long time, specially when it's overkill because all photos are contiguous anyway. So i decided I wanted something a bit quicker and simpler for that but it needed to be a carver.
So initially very bare bones I made myself a carver. It just scans for magic numbers. In case it finds:
a JPEG: It will start parsing JPEG markers from that point on so it can decide to some degree if we have a valid JPEG and for example dismiss it because it does not meet our set minimum resolution.
b TIFF based RAW: scan inside for JPEG magic number and if so so continue with a. So this allows for extracting high res previews from deleted/lost RAW photos. I have found it to be useful in case RAWs were corrupt after recovery.
To some degree it can detect and fix errors so saved result is at least a JPEG that can be opened and viewed using a photo viewer or editor.
It's defrag feature goes no further than detecting a NEW magic number inside it's contents > ride that out / skip until JPEG EOI marker is detected and continue file there. It may result in total garbage (yet formally valid JPEG).
When I decided to publish it, I needed a name for it and decided to recycle the name JpegDigger.
https://www.disktuna.com/jpegdigger-jpe ... -recovery/
I know JpegDigger has been discussed here so: JpegDigger formerly was for grabbing JPEGs from RAW photos however I discontinued it at some point as this was a feature transferred JPEG-Repair.
Last couple of months I ran into the situation where I needed JPEGs from memory cards and JPEG Recovery LAB takes such a darn long time, specially when it's overkill because all photos are contiguous anyway. So i decided I wanted something a bit quicker and simpler for that but it needed to be a carver.
So initially very bare bones I made myself a carver. It just scans for magic numbers. In case it finds:
a JPEG: It will start parsing JPEG markers from that point on so it can decide to some degree if we have a valid JPEG and for example dismiss it because it does not meet our set minimum resolution.
b TIFF based RAW: scan inside for JPEG magic number and if so so continue with a. So this allows for extracting high res previews from deleted/lost RAW photos. I have found it to be useful in case RAWs were corrupt after recovery.
To some degree it can detect and fix errors so saved result is at least a JPEG that can be opened and viewed using a photo viewer or editor.
It's defrag feature goes no further than detecting a NEW magic number inside it's contents > ride that out / skip until JPEG EOI marker is detected and continue file there. It may result in total garbage (yet formally valid JPEG).
When I decided to publish it, I needed a name for it and decided to recycle the name JpegDigger.
https://www.disktuna.com/jpegdigger-jpe ... -recovery/