Installing the Interactive Deep Colorization application in Linux

There are plenty of articles and videos on the Web regarding colourising old black and white photographs. Some of the resulting colourised photographs look amazing. Several Web sites offer free or commercial automated colourisation of B&W photographs using AI (artificial intelligence) techniques. The free-use sites watermark the result or limit the size of the original image. Some of the resulting colourised images are reasonable, others not so good.

Last year I scanned some 35 mm slides which are over 60 years old. The chemicals in some had degraded so much that the images are tinted red (‘redscale’ rather than ‘greyscale’!), too much to be able to fix using the GIMP. Out of curiosity I tried processing one of the scanned slides using some of the free online B&W photograph automated colourisers. The results in some cases were promising, alhough they would still require a lot of manual adjustment.

Scan of original 35 mm slide about 60 years old

Scan of original 35 mm slide about 60 years old

The image after processing using one of the free online B&W colouriser Websites

The image after processing using one of the free online B&W colouriser Websites

A few years ago Richard Zhang and colleagues at the University of California, Berkeley wrote software that uses similar AI techniques to colourise photographs but allows the user to manually influence the colourisation — see the Smithsonian Magazine article New App Makes It Easier to Colorize Old Photos for further information and a link to the GitHub repository of Jun-Yan Zhu with the team’s open-source software, written in Python. Zhang went on to join Adobe, and the software is now incorporated in Adobe PhotoShop Elements.

All my machines run Linux, and I wanted to try to install the open-source application from Jun-Yan Zhu’s GitHub repository. However, the Python code uses Qt4 but all my Linux installations use Qt5. Jun-Yan Zhu created a GitHub branch for the Python code to be modified for Qt5 but, to date, that branch still contains only Python code using Qt4:

https://github.com/junyanz/interactive-deep-colorization/tree/qt5

However, another GitHub user named Vishwaesh Rajiv cloned the code and ported it to Qt5 for use in a Docker container:

https://github.com/vwrj/interactive-deep-colorization

I decided to have a go at getting the application to work in Lubuntu 20.10 on my family’s desktop machine. Below are the results of my efforts, which unfortunately stalled because the machine only has 4 GB of RAM (the application apparently requires a lot of memory).

The installation instructions in the README.md file in both users’ repositories apply to the version using Qt4. Below is what I had to do to install the Qt5 version of the application from Vishwaesh Rajiv’s GitHub repository. Qt5 and PyQt5 are already installed in Lubuntu 20.10, so these are not included in the steps below (read Jun-Yan Zhu’s GitHub page for details). My family’s desktop machine does not have an NVIDIA GPU (it has an Intel IGP) so I used ‘CPU mode’ (see the README.md file for details).

user $ wget https://github.com/vwrj/interactive-deep-colorization/archive/master.zip
user $ unzip master.zip
user $ cp -r -p interactive-deep-colorization-master ideepcolor
user $ cd ideepcolor
user $ cp docker/ideepcolor_docker.py ideepcolor.py
user $ cp -r docker/ui_PyQt5/* ui/
user $ cp -r docker/data/* data/
user $ nano ideepcolor.py # Change the line 'from ui_PyQt5 import gui_design' to 'from ui import gui_design'
user $ bash ./models/fetch_models.sh
user $ sudo apt update
user $ sudo apt install caffe python3-caffe
user $ sudo apt install python3-opencv python3-sklearn python3-skimage
user $ sudo apt install python3-qdarkstyle
user $ sudo apt install python3-opencv

I used the following command in ~/ideepcolor/ to launch the application:

user $ python3 ideepcolor.py --cpu_mode --backend caffe --image_file test_imgs/parrot.jpg

From the output displayed in the terminal window the application seems to launch correctly:

[...]
Setting ab cluster centers in layer: pred_ab
Setting upsampling layer kernel: pred_313_us
b'test_imgs/parrot.jpg'
scale = 2.000000

but after a minute or two the memory used increases significantly (as seen in htop), no GUI is displayed and the terminal displays ‘Killed‘:

[...]
Setting ab cluster centers in layer: pred_ab
Setting upsampling layer kernel: pred_313_us
b'test_imgs/parrot.jpg'
scale = 2.000000
Killed

I could be wrong, but I assume the reason the application does not continue is because of insufficient RAM. When I get time I will try to install the various packages in Gentoo Linux on my main laptop with 16 GB RAM, to see if I can get it to work. If you are using a Linux installation that has Qt5 installed and your machine has plenty of RAM, you might be interested to try and install the Interactive Deep Colorization software to see if you can get it to work. If you do, please comment below.

A farewell to Sabayon Linux

After a hiatus of thirty-four months in the blog posts on the Sabayon Linux Website, a couple of posts on 20 November 2020 announced that the distribution was switching its base distribution from Gentoo Linux to Funtoo Linux (‘Sabayon and Funtoo Linux Merge Projects’), and that the distribution was rebranding (‘Sabayon project is rebranding to MocaccinoOS’) and moving to a completely different package manager named ‘Luet’. A new Website and forums for MocaccinoOS were started, and the Sabayon Linux forums and Wiki are no more.

Although my first experience of Linux was Ubuntu in 2006, it was Sabayon Linux in early 2007 that turned me into a full-time Linux enthusiast and got me interested in the Portage package manager and Gentoo Linux, which I have been using as my main OS for many years now. My interest in Sabayon Linux waned when it moved to a binary package manager (‘Entropy’), and later when it switched from OpenRC to systemd.

Unlike binary distributions, Gentoo Linux enables users to use whichever init system they choose. My Gentoo Linux installations use OpenRC rather than systemd but, occasionally, if a problem interested me, I tried to help Gentoo Linux users who had opted to use systemd. As Sabayon Linux was based on Gentoo Linux with systemd, I would occasionally install Sabayon Linux in virtual machines as a convenient way to investigate issues in Gentoo installations using systemd. Likewise I occasionally tried to help Sabayon Linux users if a problem interested me.

Despite no longer being a full-time user of the distribution, I remained one of the moderators of the Sabayon Linux forums until its demise, albeit not having much time to devote to the role in the last few years. Activity on the Sabayon Linux forums had been quite low for quite some time and I was not surprised to learn that the distribution’s developers had finally called it a day late last year and started a new project. I wish them success with the new distribution.

Moving from Lubuntu 18.04 to 20.10

The Lubuntu developers will no longer be supporting Lubuntu 18.04, the final release of Lubuntu to use LXDE, after April this year. I therefore decided to replace it with Lubuntu 20.10 on the family desktop machine (a single-seat, multi-user installation). Lubuntu 20.10 uses LXQt so it was not feasible to upgrade the existing installation, as explained on the official Lubuntu Website:

Note, due to the extensive changes required for the shift in desktop environments, the Lubuntu team does not support upgrading from 18.04 or below to any greater release. Doing so will result in a broken system. If you are on 18.04 or below and would like to upgrade, please do a fresh install.

Thus I had to install Lubuntu 20.10 from scratch. I downloaded the ISO file (1.8 GB) from the official Lubuntu Website and used the dd command to create a LivePendrive:

user $ sudo blkid # Ascertain which device is the pendrive.
user $ sudo dd bs=4M if=/home/fitzcarraldo/lubuntu-20.10-desktop-amd64.iso of=/dev/sdb conv=fdatasync status=progress

Some of my blog posts during the last three years covered various additions and fixes I made to the Lubuntu 18.04 installation on the family desktop machine. Below I explain how I implemented those, if necessary, in the fresh 20.10 installation.

Due to the automated backup routine I implemented in 2018, a permanently-connected external USB HDD (filesystem label ‘FREECOM HDD’) contained a backup of each users’ home directory from the Lubuntu 18.04 installation:

Lubuntu_home_folders_backup_LXDE/fitzcarraldo/
Lubuntu_home_folders_backup_LXDE/molly/
Lubuntu_home_folders_backup_LXDE/aquilino/
Lubuntu_home_folders_backup_LXDE/cholo/
Lubuntu_home_folders_backup_LXDE/paul/

I installed Lubuntu 20.10, overwriting the Lubuntu 18.04 installation. The resulting 20.10 installation had me as the sole user:

user $ whoami
fitzcarraldo
user $ groups
fitzcarraldo adm cdrom sudo dip plugdev lpadmin sambashare

All the files in my home directory are owned by fitzcarraldo.fitzcarraldo (user.group). I want all users to be members of the group ‘users‘ in addition to a group with their own username, so first I added myself to that group:

user $ sudo usermod -a -G users fitzcarraldo
user $ groups
fitzcarraldo adm cdrom sudo dip plugdev users lpadmin sambashare

Before using the groupadd and useradd commands I double-checked their options, as these can differ between distributions:

user $ groupadd --help
user $ useradd --help

Then I added the other users (N.B. GID and UID are not the same value per username):

user $ sudo groupadd -g 1002 molly 
user $ sudo useradd -m -c "Molly" -g molly -G adm,cdrom,dip,lpadmin,plugdev,sambashare,users -p strawberryfields -s /bin/bash -u 1001 molly
user $ sudo groupadd -g 1003 aquilino
user $ sudo useradd -m -c "Aquilino" -g aquilino -G adm,cdrom,dip,lpadmin,plugdev,sambashare,users -p paperbackwriter -s /bin/bash -u 1002 aquilino
user $ sudo groupadd -g 1004 cholo
user $ sudo useradd -m -c "Cholo" -g cholo -G adm,cdrom,dip,lpadmin,plugdev,sambashare,users -p mysweetlord -s /bin/bash -u 1003 cholo
user $ sudo groupadd -g 1005 paul
user $ sudo useradd -m -c "Paul" -g paul -G adm,cdrom,dip,lpadmin,plugdev,sambashare,users -p sweet16 -s /bin/bash -u 1004 paul

WARNING: Do not add other users to the sudo group, otherwise Muon Package Manager in Lubuntu 20.10 will not allow you to install any more packages (see [Bug 1875346] Re: Muon does not recognize user password).

Lubuntu 18.04 used the LightDM display manager, whereas Lubuntu 20.10 uses the less-sophisticated SDDM display manager. To display the avatar of each user on the SDDM login page I copied a portrait photograph of each user to the relevant SDDM directory:

user $ sudo cp /home/fitzcarraldo/Pictures/Portraits/fitzcarraldo.png /usr/share/sddm/faces/fitzcarraldo.face.icon
user $ sudo cp /home/fitzcarraldo/Pictures/Portraits/molly.png /usr/share/sddm/faces/molly.face.icon
user $ sudo cp /home/fitzcarraldo/Pictures/Portraits/aquilino.png /usr/share/sddm/faces/aquilino.face.icon
user $ sudo cp /home/fitzcarraldo/Pictures/Portraits/cholo.png /usr/share/sddm/faces/cholo.face.icon
user $ sudo cp /home/fitzcarraldo/Pictures/Portraits/paul.png /usr/share/sddm/faces/paul.face.icon

I also configured a different wallpaper for each user’s Desktop:

user $ sudo mkdir /home/molly/Pictures/Wallpaper
user $ sudo chown molly.molly /home/molly/Pictures/Wallpaper/
user $ sudo mkdir /home/aquilino/Pictures/Wallpaper
user $ sudo chown aquilino.aquilino /home/aquilino/Pictures/Wallpaper/
user $ sudo mkdir /home/cholo/Pictures/Wallpaper
user $ sudo chown cholo.cholo /home/cholo/Pictures/Wallpaper/
user $ sudo mkdir /home/paul/Pictures/Wallpaper
user $ sudo chown paul.paul /home/paul/Pictures/Wallpaper/
user $ cd Pictures/Wallpaper/
user $ sudo cp wallpaper2.jpg /home/molly/Pictures/Wallpaper/
user $ sudo chown molly.molly /home/molly/Pictures/Wallpaper/wallpaper2.jpg 
user $ sudo cp wallpaper3.jpg /home/aquilino/Pictures/Wallpaper/
user $ sudo chown aquilino.aquilino /home/aquilino/Pictures/Wallpaper/wallpaper3.jpg 
user $ sudo cp wallpaper4.jpg /home/cholo/Pictures/Wallpaper/
user $ sudo chown cholo.cholo /home/cholo/Pictures/Wallpaper/wallpaper4.jpg
user $ sudo cp wallpaper5.jpg /home/paul/Pictures/Wallpaper/
user $ sudo chown paul.paul /home/paul/Pictures/Wallpaper/wallpaper5.jpg

Note that, unlike Lubuntu 18.04, Lubuntu 20.10 does not have a ‘Switch User’ option, so it is not possible for users to switch between sessions without logging out. I actually prefer it this way, as other family members would usually switch user rather than logging out in Lubuntu 18.04, leaving open sessions.

Lubuntu 20.10 still does not automatically unmount the external HDD when a user logs out, thus making it impossible for the next user who logs in to access the external HDD (see Prevent Lubuntu 17.10 from leaving an external HDD mounted incorrectly for other users). The fix in this version of Lubuntu differs from the fix in 18.04; I added the following two lines to the end of /usr/share/sddm/scripts/Xsetup:

# Fix to make sure each user can access the external HDD
udisksctl unmount --block-device '/dev/disk/by-label/FREECOM\x20HDD'

Virus scan

I set up my automated system to scan files downloaded to the ~/Downloads directory as explained below.

user $ sudo apt install clamtk
user $ sudo apt install clamav
user $ sudo apt install clamav-daemon
user $ sudo apt install clamdscan
user $ sudo apt install inotify-tools
user $ sudo apt install kdialog # In Ubuntu this would be zenity instead.

I copied the script ~/.monitorDownloadsGUI listed below into each user’s home directory, and made the ownership <username>.<username> and the script executable:

#!/bin/bash

DIR=$HOME/Downloads

# Get rid of old log file, if any
rm $HOME/virus-scan.log 2> /dev/null

IFS=$(echo -en "\n\b")

# Optionally, you can use shopt to avoid creating two processes due to the pipe
shopt -s lastpipe
inotifywait --quiet --monitor --event close_write,moved_to --recursive --format '%w%f' $DIR | while read FILE
# Added '--recursive' so that a directory copied into $DIR also triggers clamscan/clamdscan, although downloads
# from the Web would just be files, not directories.
do
     sleep 1s
     # Have to check file length is nonzero otherwise commands may be repeated
     if [ -s $FILE ]; then
          # Replace 'date >' with 'date >>' if you want to keep log file entries for previous scans.
          date > $HOME/virus-scan.log
          clamdscan --move=$HOME/virus-quarantine $FILE >> $HOME/virus-scan.log
#         Use zenity in GNOME; kdialog in KDE and LXQt:
#          zenity --info --title="Virus scan of $FILE" --text="$(cat $HOME/virus-scan.log)"
          kdialog --title "Virus scan of $FILE" --msgbox "$(cat $HOME/virus-scan.log)"
     fi
done

I configured each user’s account to execute ~/.monitorDownloadsGUI at login. To do this in LXQt, in each user’s account I selected ‘Preferences’ > ‘LXQt settings’ > ‘Session Settings’ > ‘Autostart’.

Other useful packages

I installed the Elementary Icon Theme, as I saw some error messages about it not being installed:

user $ sudo apt install elementary-icon-theme

I installed a utility I find useful for searching for the location of a file, and ran the command to update its database of file names (you can run it at any time, or add it to e.g. crontab):

user $ sudo apt install mlocate
user $ sudo updatedb

I use Buku bookmark manager and Thunderbird e-mail client, so I installed those too:

user $ sudo apt install buku
user $ sudo apt install thunderbird
user $ sudo apt install thunderbird-locale-en

I added Buku to my crontab (the location of the binary has changed to /usr/bin/buku since I wrote my above-mentioned blog post on Buku in 2018):

1,21,41 * * * * rm /home/fitzcarraldo/ownCloud/Bookmarks/*.txt; sleep 30s && /usr/bin/buku -p --nc > /home/fitzcarraldo/ownCloud/Bookmarks/Buku_bookmarks_backup.txt

I prefer Signal to WhatsApp so I installed Signal Desktop by following the instructions at https://signal.org/download/#

Some of my family prefer the Google Chrome browser to Firefox, so I installed that:

user $ wget https://dl.google.com/linux/direct/google-chrome-stable_current_amd64.deb
user $ sudo apt install ./google-chrome-stable_current_amd64.deb

I right-clicked on the Desktop and selected ‘Create Launcher’ to create the file ~/Desktop/Google_Chrome_Web_browser.desktop for each user (I edited it to change the icon, and ticked ‘Trust this executable’ if not ticked):

[Desktop Entry]
Name=Google Chrome Web browser
GenericName=Web browser
Comment=Google Chrome Web browser
Exec=google-chrome
Type=Application
Icon=google-chrome
Terminal=false

I right-clicked on the Desktop and selected ‘Create Launcher’ to create the file ~/Desktop/Firefox_Web_browser.desktop for each user (I edited it to change the icon, and ticked ‘Trust this executable’ if not ticked):

[Desktop Entry]
Name=Firefox Web browser
GenericName=Web browser
Comment=Firefox Web browser
Exec=firefox
Type=Application
Icon=firefox
Terminal=false

I right-clicked on the Desktop and selected ‘Create Launcher’ to create the file ~/Desktop/Signal.desktop (I edited it to change the icon, and ticked ‘Trust this executable’ if not ticked):

[Desktop Entry]
Name=Signal
GenericName=Signal messenger
Comment=Signal messenger
Exec=signal-desktop
Type=Application
Icon=signal-desktop
Terminal=false

All the family use Skype, so I downloaded the .deb file from https://www.skype.com/en/get-skype/download-skype-for-desktop/ and double-clicked on it to install it.

I right-clicked on the Desktop and selected ‘Create Launcher’ to create the file ~/Desktop/Skype_for_Linux.desktop (I edited it to change the icon, and ticked ‘Trust this executable’ if not ticked):

[Desktop Entry]
Name=Skype for Linux
GenericName=Skype messaging
Comment=Skype for Linux
Exec=skypeforlinux
Type=Application
Icon=skypeforlinux
Terminal=false

I also dragged some of the icons from the Desktop to the Panel in order to create quick-launch items on the Panel, useful when frequently used items on the Desktop are obscured by open windows.

I installed and configured the utility Neofetch that can be used to display system information in a terminal window:

user $ sudo apt install xterm
user $ sudo apt install neofetch

I right-clicked on the Desktop and selected ‘Create Launcher’ to create the file ~/Desktop/Neofetch.desktop (I edited it to change the icon, and ticked ‘Trust this executable’ if not ticked):

[Desktop Entry]
Name=Neofetch
GenericName=A command-line system information tool written in Bash
Comment=A command-line system information tool written in Bash
Exec=xterm -e /bin/bash -c "neofetch; exec /bin/bash"
Type=Application
Icon=/home/fitzcarraldo/Pictures/Icons/neofetch.png
Terminal=false

Firewall

UFW (Uncomplicated Fire Wall) was already installed in Lubuntu 20.10 but not enabled, so I enabled it:

user $ sudo enable ufw
user $ sudo ufw status verbose

I edited /etc/modules-load.d/modules.conf to add two firewall-related modules needed to enable Samba commands and wsdd (see further on) to function correctly:

# /etc/modules: kernel modules to load at boot time.
#
# This file contains the names of kernel modules that should be loaded
# at boot time, one per line. Lines beginning with "#" are ignored.
iptable_raw
xt_pkttype

Bluetooth
The desktop machine has a USB Bluetooth adapter so I installed Blueman as it had not been installed by the Lubuntu 20.10 Installer:

user $ sudo apt install blueman
user $ sudo apt install --reinstall bluez

See also my blog post The phone name assigned automatically by Android on my new phone prevented Bluetooth pairing and connecting in Linux.

Samba

All the machines in my home network use broadcast NetBIOS name resolution and SMB (v2 and v3, not v1) for file sharing, so I installed the packages shown below and copied the smb.conf from the previous installation, and edited the UFW configuration file as explained in an earlier blog post.

user $ sudo apt install samba
user $ sudo apt install cifs-utils
user $ sudo apt install nbtscan
user $ sudo apt install smbclient
user $ sudo cp /media/fitzcarraldo/FREECOM\ HDD/Lubuntu_home_folders_backup_LXDE/fitzcarraldo/Samba/smb.conf /etc/samba/smb.conf

See the following blog posts for details:

As my home network includes a NAS, I also configured the user accounts to be able to mount the NAS shared folder for Windows applications running under WINE (see How to enable a Windows application in WINE to access a Samba share on a NAS (continued)):

~/Desktop/Mount_server1_user1_share.desktop

[Desktop Entry]
Name=Mount_server1_user1_share
GenericName=Mount server1 user1 share
Comment=Mount server1 user1 share
Exec=/home/fitzcarraldo/.mount_server1_user1_share.sh
Type=Application
Icon=/home/fitzcarraldo/Pictures/Icons/nuvola/128x128/devices/samba_mount.png
Terminal=true

~/.mount_server1_user1_share.sh

#!/bin/bash
mount_share () {
    echo
    echo "Enter your Linux account password below..."
    echo
    sudo ln -s /media/server1/user1 ~/$PREFIX/dosdevices/y:
    sudo mount.cifs //server1/user1/ -o user=user1,pass=<password of user1>,uid=$(id -u),gid=$(id -g) ~/$PREFIX/dosdevices/y:
}
echo
echo "This will mount the Samba share folder user1 on the server1 machine."
echo
echo
echo "== Select which WINEPREFIX you wish to use =="
echo
ls ~/.wine-* | grep .wine | awk -F'/' '{print NR " " substr($4, 1, length($4)-1)}'
NUMPREFIXES=$(ls ~/.wine-* | grep .wine | wc -l)
echo
read -p "Enter number (q to abort) and press ENTER: " CHOICE
if [ "$CHOICE" != "q" ] && [ "$CHOICE" -gt 0 ] && [ "$CHOICE" -le $NUMPREFIXES ]; then
    PREFIX=$(ls ~/.wine-* | grep .wine | awk -F'/' '{print NR " " substr($4, 1, length($4)-1)}' | grep "$CHOICE " | awk -F' ' '{print $2}')
    echo
    if [ ! -e ~/$PREFIX/dosdevices/y: ]; then
        mount_share
    else
        echo -n "~/$PREFIX/dosdevices/y: already exists. Is it OK to proceed anyway (y/n)? "
        read ANSWER
        if [ $ANSWER = "y" ]; then
            rm ~/$PREFIX/dosdevices/y:
            mount_share
        fi
    fi
    echo
fi
if grep -q "/media/server1/user1" /proc/mounts; then
    echo "Samba share //server1/user1 is mounted for WINEPREFIX ~/$PREFIX ."
else
    echo "Samba share //server1/user1 is not mounted."
fi
echo
echo "You may now close this window."
read ANSWER
exit

~/Desktop/Unmount_server1_user1_share.desktop

[Desktop Entry]
Name=Unmount_server1_user1_share
GenericName=Unmount server1 user1 share
Comment=Unmount server1 user1 share
Exec=/home/fitzcarraldo/.umount_server1_user1_share.sh
Type=Application
Icon=/home/fitzcarraldo/Pictures/Icons/nuvola/128x128/devices/samba_unmount.png
Terminal=true

~/.umount_server1_user1_share.sh

#!/bin/bash
echo
echo "This will unmount the Samba share folder user1 on the server1 machine."
echo
echo "Enter your Linux account password below..."
echo
sudo umount ~/.wine-*/dosdevices/y: 2>/dev/null
echo
if grep -q "/media/server1/user1" /proc/mounts; then
  echo "Samba share //server1/user1 is mounted."
else
  echo "Samba share //server1/user1 is not mounted."
fi
echo
echo "You may now close this window."
exit

WS-Discovery

As WS-Discovery is required to be able to browse SMB shares in File Explorer in Windows 10 installations these days, I also installed the WS-Discovery daemon. See an earlier blog post for details, including how to configure UFW: Using WS-Discovery to enable Windows 10 to browse SMB shares in my home network of Linux computers

user $ wget https://github.com/christgau/wsdd/archive/master.zip
user $ unzip master.zip
user $ sudo cp wsdd-master/src/wsdd.py /usr/bin/wsdd
user $ sudo cp wsdd-master/etc/systemd/wsdd.service /etc/systemd/system/

I added ‘--workgroup HOME‘ (the workgroup of all the machines in my home network) to /etc/systemd/system/wsdd.service and changed the group to ‘nogroup‘:

[Unit]
Description=Web Services Dynamic Discovery host daemon
; Start after the network has been configured
After=network-online.target
Wants=network-online.target
; It makes sense to have Samba running when wsdd starts, but is not required
;Wants=smb.service

[Service]
Type=simple
ExecStart=/usr/bin/wsdd --shortlog --workgroup HOME
; Replace those with an unprivledged user/group that matches your environment,
; like nobody/nogroup or daemon:daemon or a dedicated user for wsdd
User=nobody
Group=nogroup
; The following lines can be used for a chroot execution of wsdd.
; Also append '--chroot /run/wsdd/chroot' to ExecStart to enable chrooting
;AmbientCapabilities=CAP_SYS_CHROOT
;ExecStartPre=/usr/bin/install -d -o nobody -g nogroup -m 0700 /run/wsdd/chroot
;ExecStopPost=rmdir /run/wsdd/chroot

[Install]
WantedBy=multi-user.target

user $ sudo systemctl enable wsdd
user $ sudo systemctl start wsdd

I also installed a script to list WS-Discovery devices on my home network (see A Linux command-line utility to discover and list WSD-enabled computers and printers on a home network). I first copied the directory /media/fitzcarraldo/FREECOM HDD/Lubuntu_home_folders_backup_LXDE/fitzcarraldo/discover from the backup HDD to my new home directory, then I set up ~/discover/wsd-discover.sh:

user $ sudo apt install curl # curl is needed in wsd-discover.sh

As one of the awk commands in ~/discover/wsd-discover.sh would not work in Lubuntu 20.10 I changed the line:

cat /tmp/wsd-probe6.txt | awk -F "******" '{print $1 $3}' > /tmp/wsd-probe7.txt

to:

cat /tmp/wsd-probe6.txt | awk -F "\*\*\*\*\*\*" '{print $1 $3}' > /tmp/wsd-probe7.txt

The Desktop Configuration File (a.k.a. ‘Launcher’ in LXQt) ~/Desktop/Discover_WSD_devices.desktop contains the following:

[Desktop Entry]
Name=Discover_WSD_devices
GenericName=Discover WSD devices
Comment=Discover WSD devices
Exec=/home/fitzcarraldo/discover/wsd-discover.sh
Type=Application
Icon=/home/fitzcarraldo/Pictures/Icons/Crystal_Clear/png/actions/find.png
Terminal=true

I right-clicked on the Desktop and used ‘Create Launcher’ to create the above file. I edited it to change the icon, and ticked ‘Trust this executable’ if not ticked.

WINE

I installed WINE:

user $ sudo apt install wine

Then I copied across all my WINE prefix directories from the backup HDD and reconfigured them. For example, for MyPhoneExplorer:

user $ cd
user $ cp -r /media/fitzcarraldo/FREECOM\ HDD/Lubuntu_home_folders_backup_LXDE/fitzcarraldo/.wine-myphoneexplorer .
user $ export WINEPREFIX=~/.wine-myphoneexplorer
user $ winecfg
user $ cd ~/.wine-myphoneexplorer/drive_c/
user $ wine MyPhoneExplorer_Setup_v1.8.15.exe

Installing the Windows application creates a Desktop Configuration File on the Desktop. For example, the file ~/Desktop/MyPhoneExplorer.desktop contains:

[Desktop Entry]
Name=MyPhoneExplorer
Exec=env WINEPREFIX="/home/fitzcarraldo/.wine-myphoneexplorer" wine-stable C:\\\\windows\\\\command\\\\start.exe /Unix /home/fitzcarraldo/.wine-myphoneexplorer/dosdevices/c:/users/Public/Desktop/MyPhoneExplorer.lnk
Type=Application
StartupNotify=true
Path=/home/fitzcarraldo/.wine-myphoneexplorer/dosdevices/c:/users/Public/Start Menu/Programs/MyPhoneExplorer
Icon=5A9F_MyPhoneExplorer.0
StartupWMClass=myphoneexplorer.exe

user $ chmod 664 ~/Desktop/MyPhoneExplorer.desktop
user $ ls -la ~/Desktop/MyPhoneExplorer.desktop
-rw-rw-r-- 1 fitzcarraldo fitzcarraldo 436 Jan  2 02:54 /home/fitzcarraldo/Desktop/MyPhoneExplorer.desktop

ownCloud

As I use ownCloud on a server, I installed the ownCloud client (instructions are available on the ownCloud Web site):

user $ wget -nv https://download.owncloud.com/desktop/ownCloud/stable/latest/linux/Ubuntu_20.10/Release.key -O - | sudo apt-key add -
user $ echo 'deb https://download.owncloud.com/desktop/ownCloud/stable/latest/linux/Ubuntu_20.10/ /' | sudo tee -a /etc/apt/sources.list.d/owncloud.list
user $ sudo apt update
user $ sudo apt install owncloud-client

In order to be able to browse my ownCloud folder using WebDAV I installed davfs2:

user $ sudo apt install davfs2
user $ mkdir /home/fitzcarraldo/webdav

I added the following line in ~/.davfs2/secrets:

https://bsfitzgerald.ddns.net/owncloud/remote.php/webdav bsf <password for my account on my server>

I uncommented the following two lines in /etc/davfs2/davfs2.conf:

dav_user        davfs2            # system wide config file only
dav_group       davfs2            # system wide config file only

I added the following line to /etc/fstab:

https://bsfitzgerald.ddns.net/owncloud/remote.php/webdav /home/fitzcarraldo/webdav davfs noauto,user,rw 0 0

See also the following articles regarding configuring Ubuntu for WebDAV browsing:

I created the following Desktop Configuration Files to enable me to mount and unmount the WebDAV-shared folder by double-clicking on Desktop icons:

~/Desktop/Mount_server1_WebDAV_share.desktop

[Desktop Entry]
Name=Mount_server1_WebDAV_share
GenericName=Mount server1 WebDAV share
Comment=Mount server1 WebDAV share
Exec=mount /home/fitzcarraldo/webdav
Type=Application
Icon=/home/fitzcarraldo/Pictures/Icons/Crystal_Clear/png/devices/nfs_mount.png
Terminal=true

~/Desktop/Unmount_server1_WebDAV_share.desktop

[Desktop Entry]
Name=Unmount_server1_WebDAV_share
GenericName=Unmount server1 WebDAV share
Comment=Unmount server1 WebDAV share
Exec=fusermount -u /home/fitzcarraldo/webdav
Type=Application
Icon=/home/fitzcarraldo/Pictures/Icons/Crystal_Clear/png/devices/nfs_unmount.png
Terminal=true

Prevent suspending to RAM

I configured each user’s LXQt Power Management settings so none of the users’ accounts would suspend to RAM automatically. I may change this in future so I installed a script to enable me to prevent the installation suspending if desired (see How to move a mouse pointer automatically in Linux to simulate user activity):

user $ sudo apt install xdotool # My script to keep the mouse pointer moving automatically (when I run it) uses this.

I right-clicked on the Desktop and selected ‘Create Launcher’ to create the file ~/Desktop/Keep_mouse_moving.desktop below (and edited it to change the icon, and ticked ‘Trust this executable’):

[Desktop Entry]
Name=Keep_mouse_moving
GenericName=Keep mouse moving automatically
Comment=Keep mouse moving automatically
Exec=xterm -iconic -e "bash -c /home/fitzcarraldo/.keep_mouse_moving.sh"
Type=Application
Icon=input-mouse
Terminal=false

I created the script ~/.keep_mouse_moving.sh containing the following, which I can launch by double-clicking on the desktop icon when I wish:

#!/bin/bash
#
# Script to keep mouse pointer moving so that, for example, Suspend to RAM timeout does not occur.
# 
# The mouse pointer will move around its current position on the screen, i.e. around any position
# on the screen where you place the pointer. However, if you prefer it to move around the centre
# of the screen then change mousemove_relative to mousemove in the xdotool command below.
#
# Set LENGTH to 0 if you do not want the mouse pointer to move.
# Set LENGTH to 1 if you want the mouse pointer to move just a tiny fraction.
# Set LENGTH to e.g. 100 if you want to see more easily the mouse pointer move.
LENGTH=1
#
# Set DELAY to the desired number of seconds between each move of the mouse pointer.
DELAY=5
#
while true
do
#    if [[ `cat /proc/asound/card*/pcm*/sub*/status | grep RUNNING | wc -l` -ne 0 ]]; then
        for ANGLE in 0 90 180 270
        do
            xdotool mousemove_relative --polar $ANGLE $LENGTH
            sleep $DELAY
        done
#    fi
done

Automated backup of users’ home directories

I set up the same backup method that I implemented in the earlier Lubuntu installations (see Backing up users’ home directories in a Linux installation that uses systemd):

/etc/systemd/system/backup-to-usb-hdd.service

[Unit]
Description=Backup home directories of all users to USB HDD
DefaultDependencies=no
Before=shutdown.target halt.target
RequiresMountsFor=/home

[Service]
Type=oneshot
ExecStart=/usr/local/sbin/backup_home_directories.sh

[Install]
WantedBy=halt.target shutdown.target

/usr/local/sbin/backup_home_directories.sh

#!/bin/bash

# This script backs up to an external USB HDD (NTFS) labelled "FREECOM HDD" the contents of the home directories
# of the users of this Lubuntu 20.10 installation if the system is shutting down but not rebooting.
# It is launched by a systemd service /etc/systemd/system/backup-to-usb-hdd.service.

# Find out if the system is rebooting (as opposed to being shut down):
REBOOT=$( systemctl list-jobs | egrep -q 'reboot.target.*start' && echo "rebooting" || echo "not_rebooting" )
if [ $REBOOT = "not_rebooting" ]; then
# Only execute the following steps if the system is shutting down but not rebooting:
   # Clean up if the backup did not complete last time:
    umount /media/usbhdd 2>/dev/null # Make sure you enter this line correctly.
    rm -rf /media/usbhdd/* # Make sure you enter this line correctly.
    # Unmount the external USB HDD if mounted by udisks2 with the logged-in username in the path:
    umount /media/*/FREECOM\ HDD 2>/dev/null
    # Find out the USB HDD device:
    DEVICE=$( blkid | grep "FREECOM\ HDD" | cut -d ":" -f1 )
    # Create a suitable mount point if it does not already exist, and mount the device on it:
    mkdir /media/usbhdd 2>/dev/null
    mount -t ntfs-3g -o async,noexec,nodev,noatime,nodiratime $DEVICE /media/usbhdd 2>/dev/null
    # Create the backup directory on the USB HDD if it does not already exist:
    mkdir /media/usbhdd/Lubuntu_home_folders_backup 2>/dev/null
    # Backup recursively all the home directories of all the users, and add a time-stamped summary to the log file:
    echo "********** Backing up Acer Aspire XC600 users' home directories **********" >> /home/fitzcarraldo/backup.log
    date >> /home/fitzcarraldo/backup.log
    # Log username of user shutting down the PC (may not be this user if Switch User was used):
    echo -ne "User who shutdown PC (may not be this user if Switch User has been used): " >> /home/fitzcarraldo/backup.log
    last | cut -d " " -f1 | head -1 >> /home/fitzcarraldo/backup.log
    sleep 2s
    # cp --recursive --update --preserve=all --no-dereference --force /home/ /media/usbhdd/Lubuntu_home_folders_backup 2>> /home/fitzcarraldo/backup.log
    rsync --ignore-errors --recursive --times --perms --links --protect-args --exclude '/*/.cache/mozilla' --exclude '/*/.cache/google-chrome' --exclude '/*/.cache/chromium' --delete-excluded --bwlimit=22500 /home/ /media/usbhdd/Lubuntu_home_folders_backup 2>> /home/fitzcarraldo/backup.log
    echo "Copying completed" >> /home/fitzcarraldo/backup.log
    date >> /home/fitzcarraldo/backup.log
    echo "********** Backup completed **********" >> /home/fitzcarraldo/backup.log
    cp /home/fitzcarraldo/backup.log /media/usbhdd/Lubuntu_home_folders_backup/fitzcarraldo/
    # Unmount the USB HDD so that udisks2 can subsequently re-mount it with the user's username in the path:
    umount /media/usbhdd
fi
exit 0

user $ sudo systemctl enable backup-to-usb-hdd
user $ sudo systemctl start backup-to-usb-hdd

Keyboard layouts

As I want to be able to switch between English, Brazilian Portuguese and Spanish keyboard layouts, I did the following:

I added the following lines to the file /usr/share/sddm/scripts/Xsetup:

#Make sure the keyboards I use are selectable on the SDDM greeter screen
setxkbmap gb,us,br,es
#

I edited the file /etc/X11/xorg.conf.d/00-keyboard.conf so that it contains the following:

# Read and parsed by systemd-localed. It's probably wise not to edit this file
# manually too freely.
Section "InputClass"
        Identifier "system-keyboard"
        MatchIsKeyboard "on"
        Option "XkbLayout" "gb,us,br,es"
        Option "XkbModel" "pc105"
        Option "XkbOptions" "grp:alt_shift_toggle"
EndSection

I right-clicked on the Panel for each user, selected ‘Manage Widgets’ and added the ‘Keyboard state indicator’ to the Panel.

Conclusion

The resulting Lubuntu 20.10 installation is working fine so far. It has a more contemporary look than the LXDE Desktop in Lubuntu 18.04. My family is already using it and, so far, there have been no adverse comments or problems.

The phone name assigned automatically by Android on my new phone prevented Bluetooth pairing and connecting in Linux

I recently installed Lubuntu 20.10 on a desktop machine, but Bluetooth did not work with my new phone (Samsung Galaxy Note 20 Ultra with Android 11). Bluetooth had worked fine in Lubuntu 18.04 on the same desktop machine with my previous Android phone (Samsung Galaxy Note 8 with Android 9).

The first thing I discovered was that, although the Lubuntu 20.10 Installer had installed Bluez, it had not installed a Bluetooth manager, so I installed Blueman:

$ sudo apt install blueman

Then, I re-installed Bluez just to be sure:

$ sudo apt install --reinstall bluez

The Bluetooth device was detected but Lubuntu 20.10 would not pair with my new phone.

The Bluetooth device was definitely unblocked:

$ rfkill --output-all
ID TYPE      DEVICE TYPE-DESC         SOFT      HARD
 1 wlan      phy0   Wireless LAN unblocked unblocked
 2 bluetooth hci0   Bluetooth    unblocked unblocked

Now, the phone name Android 11 had assigned automatically to my new phone was Fitzcarraldo’s Galaxy Note20 Ultra 5G. After trying many things, I began to wonder if the apostrophe in the phone name was causing the problem, so I changed the name in the phone (Settings > About phone > Edit) to Fitzcarraldo Galaxy Note20 Ultra 5G. Blueman/Bluez were then able to pair with, and connect to, the phone. Problem solved, but what a silly cause.