I am trying to recover some lost images, and with all the programs I've tried, some of the photos resulted to be in a 160x120 pixel resolution. What does this mean, and is there any possibility to recover photos in original dimensions?
Any help is appreciated.
What you have there is the thumbnail stored inside a normal EXIF JPEG file.
The size 160×120 is a significant clue that this is where these thumbnails come in, because although I don't think the standard mandates a particular size, 160×120 is incredibly common. (My DSLR saves thumbnails that size, and in fact "letterboxes" the 3:2 images with black bars to fit the aspect ratio.) It must have seemed like a good idea at the time the EXIF standard was written, but these tiny thumbnails are so low quality and so small that they are rarely actually used for anything — yet most JPEG files still contain them.
Recovery software works by scanning your data disk block by disk block (or even byte by byte) regardless of any filesystem structure, looking for blocks of data which appear JPEG-like. The thumbnails are perfectly normal JPEG files themselves, so recovery software will pick them up.
If that's all you're getting, it's likely that the filesystem you're trying to recover from is so messed up that the big files can't be reconstructed, but the tiny internal thumbnails will sometimes fit in a single disk block (or maybe two together), so they're more likely to be intact. Logically, this symptom is more common when trying to recover from a highly-fragmented drive.
The recovered images might be the thumbnails and not the actual images. Some of the image programs or browsers create the thumbnails from the actual images for displaying in the GUI.
If you know any other attributes that might ascertain that the recovered image were, indeed, the actual images (location etc) then you may wish to investigate further.
As others have noted, you are seeing "thumbnails".
The originals are very likely to be there and depending on what was done to the storage medium after the photos were written, some or all may be still recoverable.
File recovery programs vary widely in capability.
Some are fully free, some cost substantial money.
I have found that the best free ones are as good as you could hope for.
Sometimes you may need to try a number of free programs to find one that works best in your situation.
On one occasion I found that the fully free Undelete 360 worked superbly when nothing else did. Worth a go. On that occasion, from a largish flash card (16 GB?) I recovered not only most of the photos the user had "lost" when they formated the card and then continued to use it, but also many going back a year+ that they had copied and then deleted on various past occasions. You may find that some other program works better in your case, but this is a good starting point.
A typical 'Undelete 360' pre-recovery screen is shown below - deleted files are shown (where possible) by name, size etc, plus likely recovery status - here you can see "very good", Bad and Overwritten estimates of file quality. If the storage media is used to write more files to after deletion or formating the chances of ecovery fall as files are fullyt or partially overwritten.
