I guess I'm now late to the party since mikesLr has marked this as solved.
And I suppose some malicious tongues will say that I wish to give
Mike_Walsh some competition. Not so.
Not that I wish to be prima donna, or worse a belladonna...
but I did publish the following slide-show script on 2016-11-09 or there abouts and it
went unnoticed. Was it on this board or in the French section or somewhere
else? But does it matter?
If started from console, this script has a few settings for viewing
-- all or an alphabetical selection of pictures in a directory
-- definition of the delay.
This is the help panel called from
Code: Select all
diapo-qiv hCode: Select all
####
# /usr/local/bin/diapo-qiv.sh
#
### Goal : slideshow with the qiv viewer. (https://spiegl.de/qiv)
### Usage (through examples)
# Open a terminal in a directory of jpg, jpeg or png images, and
# then type one of the following commands:
## 1) diapo-qiv.sh
# Will display during 6 seconds the jpg or png files in the directory
# (six seconds being the default display duration in this script);
#
## 2) diapo-qiv.sh 4
# Will display during 4 seconds the jpg or png files in the directory;
#
## 3) diapo-qiv.sh 5 B
# Displays during 5 seconds the jpg or png files in the directory
# whose name begins with B or b;
#
## 4) diapo-qiv.sh 3 B G
# Displays during 3 seconds the jpg or png files in the directory
# whose name begins with B or b, and G or g;
#
## 5) diapo-qiv.sh 7 B G M
# Displays during 7 seconds the jpg or png files in the directory
# whose name begins with B or b, G or g, and M or m;
#
## 6) diapo-qiv.sh 50 B G M X
# Displays during 50 seconds the jpg or png files in the directory
# whose name begins with B ou b, G or g, M or m, and X or x;
#
## 7) diapo-qiv.sh h
# Displays this help message.
#
### Important Notes:
# This script accepts from 0 to 5 parameters only;
# always type the duration paramater first;
# the display duration is either from 3 to 15 seconds, or
# 20, 25, 30, 40, 50, 60 or 90 seconds;
# type the 1st letter of the filename in UPPERCASE;
# this script displays images in jpg, jpeg or png formats;
# if you type a wrong character, the script will remind you;
# files with a jpeg extension will be renamed as jpg's.
#
###
# (c) Christian L'Écuyer (alias musher0 in the Puppy forum),
# Gatineau (Qc), Canada, 2016-11-09. GPL3. Rev. 2016-11-25.
####https://privatebin.net/?31d4d59423cac1c ... WfQ3Mstl0=
Seeing Mike_Walsh's panel above, I remembered that if you start from a
ROX directory full of pictures with the Shift-! hotkey and then type
< diapo-qiv > (without the chevrons) in the rectangle, it defaults to all
pictures in the dir., with an exposure (delay) of 6 seconds.
Please see screen cap.
A pet of the slide-show script is attached. The pet contains no *.desktop file
and obviously no menu entry -- since you don't need any if you start your
slide-show this way.
You will also need a separate pet or deb or rpm or whatever archive
for the qiv utility itself.
Please do not come crying to papa complaining that your slide-show does
not work if you have not downloaded and installed those two items.
As usual, people will do what they want with this.
Best regards.
Then, again, seems everyone else did as well. 
I'm quite happy to be corrected if necessary...