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Screen sharing and recording
Ferese includes a ScreenCast portal backend, xdg-desktop-portal-ferese.
Applications use the standard desktop portal to request a display, then receive
video through PipeWire. A recorder or conferencing application handles encoding,
saving files, or sending video; those tasks do not run inside the compositor.
Record from the top bar
- Click the screen-recording icon in the top bar, then Record display.
- Choose a monitor in the native picker and click Share.
- The icon changes to a stop square and shows elapsed time. Click it to stop.
The recorder finishes the video before reporting it saved. Open the recording
menu again to see its saved path. Videos are saved as VP8 WebM files under
Videos/Ferese (using your configured XDG Videos folder). Audio is off.
The icon uses the same theme accent, hover effect, and corner radius as the
other bar controls.
Encoding runs in a separate native ferese-record process using GStreamer.
The shell remains responsive while a file is recorded or finalized. If saving
fails, an error appears in the recording menu; an unfinished .webm.part file
may remain at the path shown in the error.
Start sharing
Use a Wayland screen-sharing or recording source in your application. Ferese opens a display picker. Select a display and press Share. Nothing is selected by default. Applications that request multiple displays can share up to four. The picker uses your Ferese theme colors, font, and shell corner radius.
A screen sharing window remains visible while sharing. Press Stop sharing or close that window to revoke the session. Closing the requesting application, locking Ferese, disconnecting the selected display, or changing its capture size also ends sharing. A new request needs fresh consent; selections are not saved. Everything visible on a shared display, including notifications, is included.
Installation
The standard installer builds and installs the backend, its
D-Bus activation entry, and a Ferese-specific portal preference file. Install
pipewire, a PipeWire session manager such as wireplumber,
xdg-desktop-portal, and xdg-desktop-portal-gtk using your distribution's package
manager. The GTK backend supplies other portal interfaces such as file selection.
The built-in recorder also needs GStreamer’s PipeWire, base, and good plugins
(pipewiresrc, videoconvert, vp8enc, and webmmux). The installation guide
includes these packages.
Log into a new Ferese session after installation. The session launcher imports its Wayland display into the D-Bus activation environment. Nested previews leave the host activation environment alone.
Existing custom window rules can float the picker and sharing indicator:
window-rule app-id="dev.ferese.ScreenShare" floating=#true
The packaged example configuration already includes this rule. Existing user configuration is preserved during installation.
Current capabilities
- Monitor capture, one PipeWire stream per selected display, at up to 30 fps.
- Hidden or embedded pointer, as requested by the application.
- Bounded frame storage and reusable shared-memory buffers.
- Cancellation during selection, an explicit stop control, and process cleanup.
- ScreenCast backend version 3, without persistent or automatic consent.
Window-only sharing, region selection, and audio capture in Ferese’s recorder are not implemented yet. Other recording applications can handle audio separately. Video currently uses CPU copies through the compositor's shared-memory screencopy path, not DMA-BUF zero-copy. High-resolution or multiple-display recording can therefore use significant CPU and memory bandwidth. A paused stream checks capture availability once per second so locking also ends sessions without an active consumer.
Development checks
Build the backend after installing the native dependencies in the installation guide:
cargo build --release --locked -p xdg-desktop-portal-ferese
cargo test --locked -p xdg-desktop-portal-ferese
# Exercise real video encoding and playback (requires the plugins above):
cargo test --locked -p xdg-desktop-portal-ferese --bin ferese-record encoder_finishes_a_real_webm -- --ignored
The opt-in integration test opens a temporary nested compositor and uses a
private D-Bus session. It requires built Ferese and locker binaries, Python
GI/GStreamer with pipewiresrc, dbus-daemon, xdg-desktop-portal, and bwrap.
It checks capture delivery and timestamps, cancellation, frontend loss, and lock
revocation:
FERESE_TEST_PORTAL=1 \
FERESE_TEST_PORTAL_BINARY=target/release/xdg-desktop-portal-ferese \
python3 scripts/tests/test_portal_isolated.py
Add FERESE_TEST_PORTAL_CONSENT=1 to exercise the native picker and restricted
PipeWire connection. Select the temporary display and click Share when
prompted. Tests capture only the nested preview and leave host PAM policies and
D-Bus activation unchanged.
Troubleshooting
Confirm that XDG_CURRENT_DESKTOP contains Ferese, PipeWire is running, and
FERESE_ENABLE_SCREENCOPY was not set to 0 before launching the session.
The installed preference is
/usr/share/xdg-desktop-portal/ferese-portals.conf. A user override under
~/.config/xdg-desktop-portal/ can take precedence. Its ScreenCast preference
should name ferese:
[preferred]
default=gtk;
org.freedesktop.impl.portal.ScreenCast=ferese;
If capture dimensions change, stop and start sharing again. Ferese ends the old session instead of feeding incorrectly sized frames to the application.
For development, xdg-desktop-portal-ferese --sources lists displays available
on the current WAYLAND_DISPLAY. This command does not start a stream.