DICOM browser rework

[lassoan]

Huge performance and usability improvement of DICOM browser.

DICOM indexer:

• Implemented background indexing (in worker thread): indexing may take several minutes and it is not desirable to block the entire application for this long time
• Reduced indexing time by a factor of 3x (previously, inefficient database inserts, unnecessary queries, and table view updates slowed down the insertions)
  DICOM browser:
• Removed popups from DICOM browser to not interfere with user workflow (questions, status updates, etc. are display in the browser layout)
• Do not block the GUI while importing data sets, provide continuous, detailed update about indexing progress
• Add separate displayed fields preset for DICOM query-retrieve database (this database is built without having access to the files, so less displayed fields can be computed)
• Condensed table headers in horizontal mode (one row can hold all the search/filter fields instead of using one for each)
• Set default sorting of columns (based on last insertion time, study date, and series number)
• Added option to show DICOM metadata (right-click menu)
• Added option to export datasets to file system (right-click menu)
  DICOM database:
• Remove orphan empty directories after deleting files from the database
• Emit signals when the database is opened or closed
• Added display option for specifying column that is used for sorting by default
• Improved displayed field update speed by about a factor of 100x (batch execution is very slow on sqlite and individual queries in a transaction should be used instead)
  DICOM query/retrieve:
• Fixed crash when query/retrieve was used from Python (where database cannot be passed to the Q/R widget as a shared pointer)

Many small fixes.

[pieper]

That's a huge update with lots of good stuff. Looks good to me.

@nolden will this impact MITK uses?

Are there other CTK users we should consult?

[nolden]

Amazing stuff! Thanks for the great work. Impact on MITK users will be enhanced usability :) We're using a fixed CTK version in the MITK superbuild, so I'm happy with a quick merge to CTK master and looking forward to try it out. Am 11.10.2019 um 21:00 schrieb Steve Pieper:

…

That's a huge update with lots of good stuff. Looks good to me. @nolden <https://github.com/nolden> will this impact MITK uses? Are there other CTK users we should consult? — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#886?email_source=notifications&email_token=AABVPIPBAZA3NU6E3TY42LTQODELLA5CNFSM4I7467U2YY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOEBA5JWA#issuecomment-541185240>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AABVPIJUKPQFCLNJCK2D6X3QODELLANCNFSM4I7467UQ>.

[pieper]

Alright, let's go!