[Digikam-devel] [Bug 135048] easy comparing similar pictures using a lighttable

[Arnd Baecker]

Ad Gilles, #29, not yet reflecting the comments by Luis in #30

> Do not claim than this implentation do not work in any case: it's uncomplete
> and not fully tested.

For that it does work very well ;-)

> I post this patch to have a first feedback, epecially to see if the way to have
> the Light table embedded in Album Gui is the right way.
>
> I'm not fully satisfied by it (:=))). I think than light table must be a
> separate tool like Image Editor... But i'm not sure...


To me it does look like the right way - having another tool,
in a separate window, would lead to a less coherent appearance,
I think. Image selection (via the light table),
and rating and tagging are quite closely related, so
they should appear in the same framework
(e.g. sometimes it is only possible by zooming into a picture
to distinguish one type of duck from another;
but zooming into a picture is already necessary to judge
sharpness. So in a sense these two steps, selection and tagging,
can be done in one go).

Before going into the details, maybe it is worth
to think about the possible workflow:
a) Situation: several similar images
   Aim: select the best (according to whatever criterion) of them
b) select the relevant images in the Album view
   and add them to the light-table thumbs
c) all (or a subset?) of them will be displayed in the middle,
   as large as possible.
   Joint zooming and panning allows to see
   a magnified view of all selected images
d) Select the best one:
   - kick out images from the light-table view or
   - rate images

That's all. (or is anything missing?...;-)
Of course there might be different ways to set up the workflow
(so the opinion of users which have experience with
other software is definitively helpful).

Concerning c):
I am not sure if the default should be to display
just all thumbs placed in the lighttable
(otherwise we would have another selection step)?
It might be nice to be able to display the current picture
just alone in the middle (i.e., as it is at the moment) and
quickly switch back to the comparison view, where all
are shown. (But presumably  this is a minor detail at this point).

For d) one could use an additional color
label (eg. red, yellow, green, blue, and purple)
as available in other applications .

> Of course the tool do not provide yet the way to compare image. The light table
> sidebar tab is just a container to group the image to compare. When you select
> an idem, it appear on the center using preview mode. You can just pan/scroll...
>
>
> To add a picture to light table container, just use the pop-up menu with album
> view and select the "Insert item to Light Table"
>
> Limitation : the items cannot be yet removed from Light Table. digiKam do not
> remember yet the items list in Light Table between session... and certainly
> others stuff of course.
>
> Please, try to be contructive. This is not yet time to request specific missing
> features for Light Table. The implementation is in alpha stage...

There are of course a couple of *small* glitches
(just let me know if you would like to have a list
already at this point).

To mention one point already now:
I find the following a bit confusing:
- Go to Album view in a folder with images
- go to the light-table (empty or non empty, does not matter):
  now the images of the previous album folder are still displayed

Changing to the light-table side-bar should just display
the first (or later all) of its images in the middle.
(After changing to one of the thumbs in the ligtht-table,
this works as expected, so maybe it is just a simple initializatoin
call missing when selecting the light-table view).

Best, Arnd