Arch Linux User Repository

I get an error when connecting to the camera

droidcam
Video: /dev/video0
Audio: hw:0,1,0

(droidcam:514803): Gtk-CRITICAL **: 09:56:36.979: gtk_widget_get_scale_factor: assertion 'GTK_IS_WIDGET (widget)' failed
free(): invalid size
fish: Job 1, 'droidcam' terminated by signal SIGABRT (Abort)

I experience frequent crashes with this package lately, which seem to be caused by dynamically linked libjpeg-turbo. The official release from GitHub works well.

Would you consider switching this package to statically linked libjpeg-turbo like the developer recommends?

https://github.com/dev47apps/droidcam-linux-client/issues/305

The last errors on current Manjaro (continuing from the previous comment):

==> Building image from preset: /etc/mkinitcpio.d/linux-ck.preset: 'default'
==> Using default configuration file: '/etc/mkinitcpio.conf'
  -> -k /boot/vmlinuz-linux-ck -g /boot/initramfs-linux-ck.img
==> ERROR: Invalid option -k -- '/boot/vmlinuz-linux-ck' must be readable
==> Building image from preset: /etc/mkinitcpio.d/linux-ck.preset: 'fallback'
==> Using default configuration file: '/etc/mkinitcpio.conf'
  -> -k /boot/vmlinuz-linux-ck -g /boot/initramfs-linux-ck-fallback.img -S autodetect
==> ERROR: Invalid option -k -- '/boot/vmlinuz-linux-ck' must be readable
error: command failed to execute correctly

Warnings and errors (though it did get updated) on current Manjaro x64. At least some are because of upstream, but unsure if all are so.

yay
...
1  aur/v4l2loopback-dc-dkms  1:2.1.4-1 -> 1:2.1.5-1
...
==> Checking buildtime dependencies...
==> WARNING: Using existing $srcdir/ tree
...
src/decoder_snd.c: In function ‘find_snd_device’:
src/decoder_snd.c:291:26: warning: format ‘%ld’ expects argument of type ‘long int’, but argument 4 has type ‘int’ [-Wformat=]
  291 |                 errprint("Unexpected audio device buffer size: %ld expected %ld\n",
      |                          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
src/common.h:35:39: note: in definition of macro ‘errprint’
   35 | #define errprint(...) fprintf(stderr, __VA_ARGS__)
      |                                       ^~~~~~~~~~~
src/decoder_snd.c:291:79: note: format string is defined here
  291 |                 errprint("Unexpected audio device buffer size: %ld expected %ld\n",
      |                                                                             ~~^
      |                                                                               |
      |                                                                               long int
      |                                                                             %d
...
src/decoder_snd.c:291:26: warning: format ‘%ld’ expects argument of type ‘long int’, but argument 4 has type ‘int’ [-Wformat=]
  291 |                 errprint("Unexpected audio device buffer size: %ld expected %ld\n",
      |                          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
src/common.h:35:39: note: in definition of macro ‘errprint’
   35 | #define errprint(...) fprintf(stderr, __VA_ARGS__)
      |                                       ^~~~~~~~~~~
src/decoder_snd.c:291:79: note: format string is defined here
  291 |                 errprint("Unexpected audio device buffer size: %ld expected %ld\n",
      |                                                                             ~~^
      |                                                                               |
      |                                                                               long int
      |                                                                             %d
...
(2/3) Install DKMS modules
==> dkms install --no-depmod v4l2loopback-dc/2.1.5 -k 6.18.8-1-MANJARO
Deprecated feature: CLEAN (/usr/src/v4l2loopback-dc-2.1.5/dkms.conf)
==> dkms install --no-depmod v4l2loopback-dc/2.1.5 -k 6.12.68-1-MANJARO
Deprecated feature: CLEAN (/var/lib/dkms/v4l2loopback-dc/2.1.5/source/dkms.conf)
==> dkms install --no-depmod v4l2loopback-dc/2.1.5 -k 6.19.0-rc7-1-MANJARO
Deprecated feature: CLEAN (/var/lib/dkms/v4l2loopback-dc/2.1.5/source/dkms.conf)
...
==> depmod 6.18.8-1-MANJARO
==> ERROR: Missing 5.10.248-1-MANJARO kernel modules tree for module v4l2loopback-dc/2.1.5.
(3/3) Updating linux initcpios...
==> Building image from preset: /etc/mkinitcpio.d/linux519.preset: 'default'
==> Using configuration file: '/etc/mkinitcpio.conf'
  -> -k /boot/vmlinuz-5.19-x86_64 -c /etc/mkinitcpio.conf -g /boot/initramfs-5.19-x86_64.img
==> ERROR: Invalid option -k -- '/boot/vmlinuz-5.19-x86_64' must be readable
==> Building image from preset: /etc/mkinitcpio.d/linux519.preset: 'fallback'
==> Using configuration file: '/etc/mkinitcpio.conf'
  -> -k /boot/vmlinuz-5.19-x86_64 -c /etc/mkinitcpio.conf -g /boot/initramfs-5.19-x86_64-fallback.img -S autodetect
==> ERROR: Invalid option -k -- '/boot/vmlinuz-5.19-x86_64' must be readable
==> Building image from preset: /etc/mkinitcpio.d/linux60.preset: 'default'
==> Using configuration file: '/etc/mkinitcpio.conf'
  -> -k /boot/vmlinuz-6.0-x86_64 -c /etc/mkinitcpio.conf -g /boot/initramfs-6.0-x86_64.img
==> ERROR: Invalid option -k -- '/boot/vmlinuz-6.0-x86_64' must be readable
==> Building image from preset: /etc/mkinitcpio.d/linux60.preset: 'fallback'
==> Using configuration file: '/etc/mkinitcpio.conf'
  -> -k /boot/vmlinuz-6.0-x86_64 -c /etc/mkinitcpio.conf -g /boot/initramfs-6.0-x86_64-fallback.img -S autodetect
==> ERROR: Invalid option -k -- '/boot/vmlinuz-6.0-x86_64' must be readable
==> Building image from preset: /etc/mkinitcpio.d/linux612.preset: 'default'
==> Using default configuration file: '/etc/mkinitcpio.conf'
  -> -k /boot/vmlinuz-6.12-x86_64 -g /boot/initramfs-6.12-x86_64.img

and more - but over a limit of a comment length here, so I will post a separate comment.

You need to add linux-headers as a dependency

Seems like ffmpeg now has libswscale.so.9 so this fails again (looking for libswscale.so.8).

ffmpeg 2:8.0-3.1 (CachyOS has optimized rebuilds so AFAIK it's just 2:8.0-3)

Cleared my cache and reinstalled droidcam, that indeed did the trick, Thank you!

What's your ffmpeg version? Try reinstalling the package.

If you need help, my email is in the PKGBUILD (click on "View PKGBUILD" on the right-hand side).

Hello, still rather new to Arch :)

I have issues getting droidcam to run on a current install (CachyOS). ffmpeg seems to have updated recently, resulting in the following error when trying to run droidcam or droidcam-cli:

error while loading shared libraries: libswscale.so.8: cannot open shared object file: No such file or directory

I traced back libswscale to belonging to ffmpeg. Does that mean droidcam requires a rebuild with new ffmpeg?

I've made a zsh script to automate the installation. Note that there is an error with pkgbuild that I fixed using dos2unix. The main reason of this script is to use FULL HD resolution:

#
# Installs and configures Droidcam from the AUR, with the resolution modified to 1080p.
#
# USAGE:
#   install_droidcam
#
# WHAT IT DOES:
# 1. Creates a safe, temporary working directory.
# 2. Checks for and installs the 'dos2unix' dependency if needed.
# 3. Downloads the Droidcam build files from the AUR.
# 4. Uses 'sed' to change the resolution to 1920x1080 in the PKGBUILD.
# 5. Fixes the file format (dos2unix) to prevent errors.
# 6. Updates checksums (updpkgsums) to ensure validation.
# 7. Compiles and installs the package non-interactively (makepkg -si --noconfirm).
# 8. Loads the kernel module with the new settings.
# 9. Cleans up the temporary working directory upon completion.
#
install_droidcam() {
  # Stop the script if any command fails
  set -e

  # Create a safe temporary directory to avoid cluttering the home folder
  local build_dir
  build_dir=$(mktemp -d -t droidcam-build-XXXXXX)
  echo ">>> Using temporary build directory: ${build_dir}"

  # Ensure the temporary directory is removed on exit, even on error
  trap 'echo ">>> Cleaning up build directory..."; rm -rf -- "$build_dir"' EXIT

  # Enter the temporary directory
  cd "$build_dir"

  echo -e "\n[ STEP 1/7 ] Checking for 'dos2unix' dependency..."
  if ! command -v dos2unix &> /dev/null; then
    echo "--> 'dos2unix' not found. Installing via pacman..."
    sudo pacman -S --noconfirm dos2unix
  else
    echo "--> 'dos2unix' is already installed."
  fi

  echo -e "\n[ STEP 2/7 ] Downloading Droidcam files (AUR)..."
  paru -G droidcam

  # Enter the package directory
  cd droidcam

  echo -e "\n[ STEP 3/7 ] Modifying PKGBUILD for 1920x1080 resolution..."
  sed -i 's/width=640 height=480/width=1920 height=1080/g' PKGBUILD
  echo "--> Modification complete."

  echo -e "\n[ STEP 4/7 ] Correcting file format (dos2unix)..."
  dos2unix PKGBUILD

  echo -e "\n[ STEP 5/7 ] Updating checksums in PKGBUILD..."
  updpkgsums

  echo -e "\n[ STEP 6/7 ] Building and installing the package (may ask for your password)..."
  makepkg -si --noconfirm

  echo -e "\n[ STEP 7/7 ] Loading the kernel module (may ask for your password)..."
  sudo modprobe -v v4l2loopback_dc

  # The 'trap' will handle the cleanup
  set +e

  echo -e "\n✅ Process complete! Droidcam has been successfully installed and configured."
}