[kwlug-disc] Image viewer that can build up a slideshow

[Steve Izma]

On Mon, Jan 29, 2024 at 08:58:21AM -0500, Paul Nijjar via kwlug-disc wrote:
> Subject: [kwlug-disc] Image viewer that can build up a slideshow
> 
> I want to make four invocations of an image viewer and have the
> images added to a slideshow. The first invocation should launch
> the image viewer. The second through fourth should add the
> listed images to the image viewer, so that I can build up a
> slideshow in a single window. Ideally the latest image I invoke
> should be the one that is displaying, but then I want to be
> able to scroll through the rest.
> 
> I want to launch the image viewer with a single commandline
> command, providing the image filename as an argument. 
> 
> Ideally this imageviewer would be lightweight.

I can suggest a couple of alternatives that might be worth
considering. I prefer lightweight as well -- in fact I prefer
primitive, e.g., filesystem links, vi, and a simple viewer of
images in a directory.

I had to do something like this last week: assembling a slide
show with captions of pictures of my various recent trips to
Lebanon. My family has collected a couple of thousand images of
hiking in the Lebanese mountains over the last seven years. I
keep these images in a hierarchy organized by year and month.

For this project I set up a new directory and filled it with
links to the original images, naming the links in the order in
which I wanted to show the pictures. This allowed the use of a
viewer like  gwenview on that directory in full-screen mode. A
single key press moves forward or backwards in the slides.

To easily create the links, I ran something like:

find /media/pix/{2017/0[45],2019/05,2023/04,2023/05} > temp

Since most of the images are complicated number-based names from
the camera, I never need to type them out. I start up a 2-window
vim session including the above temp file and a blank file in the
new directory. I open up an image viewer, sub-directory by
sub-directory, to find the images I want, search for the image
name in temp using a minimal search string (usually four of the
digits of the image is good enough), then copy the pathname of
the file to the new file. Once I have the list of source files,
e.g.:

/media/pix/2023/05/bh_7266_qadisha_hike.png

I add a simple name for ordering, then globally prepend ln -s to
each line.

ln -s /media/pix/2023/05/bh_7266_qadisha_hike.jpg 001.jpg

Then I just run sh on the file to create the links.

But, in fact, for the presentation, since I wanted to add
captions, I created a PDF instead, using another great primitive
tool, groff.

Instead of linking the above images, I needed to run a convert
(from imagemagick) on each file to create EPS images, since I use
groff in PS-output mode. Also, I've found that using eps2eps
(from the psutils package) on imagemagick-produced EPS's
"distills" them into a more palatable form for groff, but such
batch files are pretty simple to do.

Since I've been addicted to typography (for a long time, it was a
nice way to make a living) I created a straight-forward groff
source file of landscape pages with one or two images (again,
copying image file names from vim buffer to buffer) with
captions in the appropriate place. At the presentation I simply
ran okular on the resulting PDF on my laptop, which was connected
to a projector. Again, a single keystroke moved forward or
backward through the PDF.

I hardly had to use the mouse at all during the entire process.

For the next couple of weeks, you can see the results, if you're
interested in the peaceful side of Lebanon, here:

https://www.dropbox.com/scl/fi/dtjaehcszz0cd59x2wpzd/lebanon.pdf?rlkey=c51ig0dm1qfu41u0e8azax3bl&dl=0

Hope this helps stimulate some simpler ideas.

	-- Steve

P.S.: Thanks to everybody to gave advice on dealing with
fire-damaged equipment. I'm still trying to sort out issues with
the insurance company.

-- 
Steve Izma
-
Home: 35 Locust St., Kitchener, Ontario, Canada  N2H 1W6
E-mail: sizma at golden.net  cellphone: 519-998-2684

==
The most erroneous stories are those we think we know best – and
therefore never scrutinize or question.
    -- Stephen Jay Gould, *Full House: The Spread of Excellence
       from Plato to Darwin*, 1996