Moving Subsurface photos between directories

[Willem Ferguson]

Robert,


Please look through the following paragraph for the user manual, will you?

Your system provides pretty sophisticated image management. None of the 
image management software that I use includes such automatic remapping 
of image locations. Its impressive.

Three suggestions to make the management of images using hash sums more 
smooth:

1) If I understand it correctly there is a problem in calculating hashes 
for each photo already associated with a dive in Subsurface. That is, to 
update the existing dive log so that all photos have valid hash sums in 
XML. It appears to me that, in order to do this, one has to force 
Subsurface to save a dive while the photos are shown for that dive. In 
large photo collections over large numbers of dives this may be a very 
tedious and somewhat risky job: Open each dive individually, Do some 
changes to dive details, save update for that dive. IF I AM CORRECT, I 
think there is a big need for a facility that determines whether a) 
there is an existing XML hash attribute for each image, b) if so, 
whether the XML hash sum for each image is a valid hash sum, c) if there 
is no hash sum or an invalid hash sum (e.g. ""), then to calculate the 
hash sum for the image and write that into the XML.  Is my understanding 
of this correct? Because this is a once-of type of activity, such a 
facility should probably be activated by a command line option, not from 
within the GUI.

2) The option "Hash images" in the main menu is a bit cryptic for 
non-technical users. I would suggest "Find moved images" or something 
similar ??

3) Any way of reusing the same bottom blue bar shown while converting a 
XML dive log to the new XML format? Some type of visual feedback while 
doing the hash sum calculations and updating for all images is crucial.

Kind regards,
willem

[[Moving_images]]
==== Moving photographs among directories, hard disks or computers

After a photograph has been loaded into _Subsurface_ and associated with 
a specific dive, the directory
  where the photo lies is stored, allowing _Subsurface_ to find the 
photograph when the dive is
  opened again. If the photo or the whole photo collection is moved to 
another drive or to a different
  machine, it is unlikely that the directory structure will remain 
identical to that of the original uploaded
  photo. When this happens, _Subsurface_ looks for the photos at their 
original location before they were moved,
  cannot find them and therefore cannot display them. Because, after 
moving photos, large numbers of photos
  may need to be deleted and re-imported from the new location, 
_Subsurface_ has a mechanism that eases the
  process of updating the directory information for each photo: 
automatic updates using fingerprints.

When a photo is loaded into _Subsurface_, a fingerprint for the image is 
calculated and stored with the
  other reference information for that photo. After moving a photo 
collection (that has already been loaded
  into _Subsurface_) to a different directory, disk or computer, 
_Subsurface_ can  perform the
  following steps:

- look through a particular directory (and all its subdirectories 
recursively) where photos have been moved
  to,

- calculate fingerprints for all photos in this directory, and

- if there is a match between a calculated fingerprint and the one 
originally calculated when a photo was
  loaded into _Subsurface_ (even if the original file name has changed), 
to automatically update the
  directory information so that _Subsurface_ can find the photo in the 
new moved directory.

This is achieved by selecting from the Main Menu: _File  ->  Hash 
images_. This brings up a window within
  which the NEW directory of the photos needs to be specified. Select 
the appropriate directory and click
  the _Scan_ button towards the bottom right of the panel. The process 
may require several minutes to
  complete, after which _subsurface_ will show the appropriate 
photographs when a particular dive is opened.