How do I install it?


Linux
Bionic (18.04): Repository (amd64) Binary Packages Focal (20.04): Repository (amd64) Binary Packages Groovy (20.10): Repository (amd64) Binary Packages Hirsute (21.04): Repository (amd64) Binary Packages
Run following in terminal as root:

                  echo 'deb http://download.opensuse.org/repositories/home:/maxrd2/xUbuntu_18.04/ /' | sudo tee /etc/apt/sources.list.d/home:maxrd2.list
curl -fsSL https://download.opensuse.org/repositories/home:maxrd2/xUbuntu_18.04/Release.key | gpg --dearmor | sudo tee /etc/apt/trusted.gpg.d/home_maxrd2.gpg > /dev/null
sudo apt update
sudo apt install subtitlecomposer
Run following in terminal as root:

                  echo 'deb http://download.opensuse.org/repositories/home:/maxrd2/xUbuntu_20.04/ /' | sudo tee /etc/apt/sources.list.d/home:maxrd2.list
curl -fsSL https://download.opensuse.org/repositories/home:maxrd2/xUbuntu_20.04/Release.key | gpg --dearmor | sudo tee /etc/apt/trusted.gpg.d/home_maxrd2.gpg > /dev/null
sudo apt update
sudo apt install subtitlecomposer
Run following in terminal as root:

                  echo 'deb http://download.opensuse.org/repositories/home:/maxrd2/xUbuntu_20.10/ /' | sudo tee /etc/apt/sources.list.d/home:maxrd2.list
curl -fsSL https://download.opensuse.org/repositories/home:maxrd2/xUbuntu_20.10/Release.key | gpg --dearmor | sudo tee /etc/apt/trusted.gpg.d/home_maxrd2.gpg > /dev/null
sudo apt update
sudo apt install subtitlecomposer
Run following in terminal as root:

                  echo 'deb http://download.opensuse.org/repositories/home:/maxrd2/xUbuntu_21.04/ /' | sudo tee /etc/apt/sources.list.d/home:maxrd2.list
curl -fsSL https://download.opensuse.org/repositories/home:maxrd2/xUbuntu_21.04/Release.key | gpg --dearmor | sudo tee /etc/apt/trusted.gpg.d/home_maxrd2.gpg > /dev/null
sudo apt update
sudo apt install subtitlecomposer
Debian 10: Repository (i386 / amd64) Binary Packages Unstable: Repository (amd64) Binary Packages Testing: Repository (amd64) Binary Packages
Run following in terminal as root:

                  echo 'deb http://download.opensuse.org/repositories/home:/maxrd2/Debian_10/ /' | sudo tee /etc/apt/sources.list.d/home:maxrd2.list
curl -fsSL https://download.opensuse.org/repositories/home:maxrd2/Debian_10/Release.key | gpg --dearmor | sudo tee /etc/apt/trusted.gpg.d/home_maxrd2.gpg > /dev/null
sudo apt update
sudo apt install subtitlecomposer
Run following in terminal as root:

                  echo 'deb http://download.opensuse.org/repositories/home:/maxrd2/Debian_Unstable/ /' | sudo tee /etc/apt/sources.list.d/home:maxrd2.list
curl -fsSL https://download.opensuse.org/repositories/home:maxrd2/Debian_Unstable/Release.key | gpg --dearmor | sudo tee /etc/apt/trusted.gpg.d/home_maxrd2.gpg > /dev/null
sudo apt update
sudo apt install subtitlecomposer
Run following in terminal as root:

                  echo 'deb http://download.opensuse.org/repositories/home:/maxrd2/Debian_Testing/ /' | sudo tee /etc/apt/sources.list.d/home:maxrd2.list
curl -fsSL https://download.opensuse.org/repositories/home:maxrd2/Debian_Testing/Release.key | gpg --dearmor | sudo tee /etc/apt/trusted.gpg.d/home_maxrd2.gpg > /dev/null
sudo apt update
sudo apt install subtitlecomposer
Add the following to /etc/pacman.conf (need to edit as root):

                [home_maxrd2_Arch]
# Subtitle Composer
SigLevel = Optional TrustAll
Server = https://downloadcontent.opensuse.org/repositories/home:/maxrd2/Arch/x86_64/
Repository and packages are signed with GPG key DE85E73C17AF00C8E865B04F0073ABF073738FA0.
Update/install key as root:

                wget -O - https://build.opensuse.org/projects/home:maxrd2/public_key | pacman-key --add -
pacman-key --lsign-key DE85E73C17AF00C8E865B04F0073ABF073738FA0
Finally install the package as root:
pacman -Sy subtitlecomposer-git
Tumbleweed: Repository (i586 / x86_64) Binary Packages Leap 15.1: Repository (x86_64) Repository (PowerPC) Binary Packages Leap 15.2: Repository (x86_64) Repository (PowerPC) Binary Packages Leap 15.3: Repository (x86_64 / PowerPC) Binary Packages
Run following in terminal as root:

                  zypper addrepo https://download.opensuse.org/repositories/home:maxrd2/openSUSE_Tumbleweed/home:maxrd2.repo
zypper refresh
zypper install subtitlecomposer
Run following in terminal as root:

                  zypper addrepo https://download.opensuse.org/repositories/home:maxrd2/openSUSE_Leap_15.1/home:maxrd2.repo
zypper refresh
zypper install subtitlecomposer
Run following in terminal as root:

                  zypper addrepo https://download.opensuse.org/repositories/home:maxrd2/openSUSE_Leap_15.1_PowerPC/home:maxrd2.repo
zypper refresh
zypper install subtitlecomposer
Run following in terminal as root:

                  zypper addrepo https://download.opensuse.org/repositories/home:maxrd2/openSUSE_Leap_15.2/home:maxrd2.repo
zypper refresh
zypper install subtitlecomposer
Run following in terminal as root:

                  zypper addrepo https://download.opensuse.org/repositories/home:maxrd2/openSUSE_Leap_15.2_PowerPC/home:maxrd2.repo
zypper refresh
zypper install subtitlecomposer
Run following in terminal as root:

                  zypper addrepo https://download.opensuse.org/repositories/home:maxrd2/openSUSE_Leap_15.3/home:maxrd2.repo
zypper refresh
zypper install subtitlecomposer

AppImage is a self-contained executable with all dependencies included that runs on any Linux system.

It’s quite simple to run AppImages. All you have to do is download them, make them executable and run them.
Here's more details on how to run AppImage.

Download: AppImage (x86_64) AppImage.zsync
Add the KDE Apps nightly repository:

                flatpak remote-add --user --if-not-exists kdeapps --from https://distribute.kde.org/kdeapps.flatpakrepo
Then install the flatpak:
flatpak install org.kde.subtitlecomposer
Subtitle Composer is already available on most Linux distributions.
You can install it from the KDE Software Center.
Windows Download: Setup (x86) Sources Clone the git repository:

          git clone https://invent.kde.org/multimedia/subtitlecomposer.git
        
Instructions for building from sources can be found on the wiki page.