I have a lot of family pictures saved in Google Drive as JPEGs - not JPEG 2000 - as they were initially acquired.
I thought the problem with JPEGs was artifact at sharp edges, which is not too much of an issue with landscape and family pictures, but I recently have become concerned about the fact that I read there is progressive loss every time they are opened.
Should I save each one of them as a PNG (or TIFF)? Space is not an issue.
There is no data loss from simply opening them, only by changing them & re-saving.
Any data already lost can never be recovered.
Simply converting now to a lossless format will not change the images from what they currently show.
I recently have become concerned about the fact that I read there is progressive loss every time they are opened.
Opening an image without editing and resaving does not alter it. However, xenoid points out [1, 2] that this misconception may have been perpetuated by the behavior of some versions of Windows Picture Viewer in Windows XP, where some edits, such as rotation, were silently saved to disk without notifying the user.
Should I save each one of them as a PNG (or TIFF)?
If concern about quality loss from viewing them is the sole reason for conversion, you should leave them alone. Other reasons you may have to convert should be evaluated independently.
I have a lot of family pictures saved in Google Drive as JPEGs - not JPEG 2000 - as they were initially acquired.
Most people who regularly work with images would have recommended saving a copy of the original in whatever format they happen to be in.
See also:
For digital preservation, I find the following optimal:
RAW is as close as possible to what the sensor sees. Even PNG has some losses, including losses from denoising and demosaicing algorithms. RAW has none of those losses. For digital photography, anything including denoising and demosaicing is not lossless.
However, RAW requires a capable software to interpret the data. It is not an image, it is raw data from the sensor. It becomes an image only after interpretation.
Software changes over time. Thus, the interpretation of RAW changes. It will probably improve over time, but some changes may actually end up being negative for some rare images. Also, can you after 30 years find a software for the operating systems used then for a 30-year old camera? Perhaps, perhaps not.
By storing JPEG too, you are ensuring you at least have something to work with if the RAW image requires too much effort to convert to a lossless format using the software of the future.
The JPEG takes minimal additional space compared to RAW.
As already explained, there is absolutely no benefit to convert JPEG to PNG as the losses are already there. JPEG cannot be converted to RAW in practice.
Lots of long answers here.
Should I convert my family pictures from JPEG to PNG?
NO!
but I recently have become concerned about the fact that I read there is progressive loss every time they are opened.
Incorrect, quality is only lost if they are re-saved as JPEG, such as after editing. Never delete/overwrite the original JPEG files
Using a program like Photoshop Lightroom will help you keep a catalog of original images safe, because it stores edits as metadata, and will always create a copy when editing with an external editor.
