Fit an app window to a video shape (16:9, 9:16, 1:1, 4:3) and record it, ready to upload. No cropping, no black bars, no editing afterwards.

Command: srec (or the long name simple-recorder).

Watch the 47-second video. Full guide: thetechbasket.com/simple-recorder.

$ srec chrome

  Window   google-chrome | Docs - Google Chrome
  Preset   youtube window 16:9 video 1920x1080 at 60 fps
  Audio    microphone
  Encoder  h264_nvenc (NVIDIA GPU)
  File     ~/Videos/simple-recorder/google-chrome-youtube-2026-10-01-201500.mkv

  ● REC  00:01:12    18MB   60.0 fps  7 dropped   1.00x   q to stop

1. You pick a window: by name (srec firefox) or from a list (srec).
2. You pick a preset: YouTube, Shorts, square and others. Enter takes the default.
3. srec resizes the window to the exact shape of the preset, as large as your screen allows. It removes the title bar, brings the window to the front and keeps it on top, so a window you click cannot cover the recording.
4. ffmpeg records only that window and scales it to the video size, for example 1920x1080.
5. Press q to stop. The title bar comes back and on-top goes back to how it was.

The recording follows the window, so you can move it while you record.

npm install -g simple-recorder

Or without npm (the script from the latest release; releases/download/v0.1.0/srec for a fixed version, SHA256SUMS next to it to check the download):

curl -fLo ~/.local/bin/srec https://github.com/Amitind/simple-recorder/releases/latest/download/srec
chmod +x ~/.local/bin/srec

Fedora RPM: build it yourself or publish it on COPR, see packaging/README.md.

sudo dnf install ffmpeg xprop qt6-qttools fzf pulseaudio-utils      # Fedora (ffmpeg from RPM Fusion)
sudo apt install ffmpeg x11-utils qdbus-qt6 fzf pulseaudio-utils    # Debian, Ubuntu
sudo pacman -S ffmpeg xorg-xprop qt6-tools fzf libpulse             # Arch

• Wayland does not work yet. On the login screen, pick "Plasma (X11)".
• PipeWire works too (through its PulseAudio layer, the default on current distros).
• On Fedora, the stock ffmpeg-free has no libx264. Install ffmpeg from RPM Fusion (sudo dnf swap ffmpeg-free ffmpeg --allowerasing).
• Debian and Ubuntu put qdbus at /usr/lib/qt6/bin/qdbus. srec finds it there.

If something is missing, srec lists every problem at once with the install command for your distro.

srec                       # pick window and preset from lists
srec chrome                # window by class or title
srec -p shorts discord     # preset by name, no list
srec -a both chrome        # audio: mic | sys | both | none
srec -f 30 chrome          # frames per second
srec chrome demo.mkv       # choose the output file (demo-2.mkv if it exists)
srec -r chrome             # resize only, do not record
srec setup                 # choose your defaults step by step (runs on first start)
srec config                # edit every setting
srec config reset          # fresh config with all defaults (old one kept as .bak)
srec -h                    # help

Your own presets go in the config under ## Your presets and are listed first when you pick. A built-in preset you change shows as edited in the list, with its original values next to it, and as (edited) on the recording screen. srec config reset asks whether to keep yours.

A ratio window (16:9) becomes the largest window of that shape that fits between your panels. The video is then scaled to the preset size. For sharp, unscaled video, use an exact size and set your panels to auto-hide.

~/.config/simple-recorder/config, in the key = value format that mpv, git and systemd use. The first start runs srec setup, which asks for the main choices and writes the file. The file holds every setting with its default, grouped as Basic and Advanced:

## Basic
default_preset = youtube             # preset used when you press Enter (default: youtube)
ask_preset = yes                     # show the preset list each run (default: yes)
fps = 60                             # frames per second (default: 60)
mic = yes                            # record the microphone (default: yes)
system_audio = no                    # record the sound your computer plays (default: no)
ask_audio = yes                      # show the audio list each run (default: yes)
out_dir = ~/Videos/simple-recorder   # where videos are saved (default: ~/Videos/simple-recorder)

## Advanced (most people never change these)
mic_device = default                 # default, or a source name (srec setup lists them)
separate_audio = no                  # also save mic and system sound as their own .m4a files
encoder = auto                       # auto, libx264 (CPU) or h264_nvenc (NVIDIA GPU)
quality = 18                         # lower is better and bigger
speed = veryfast                     # libx264 only
audio_bitrate = 192k
show_cursor = yes
container = mkv                      # mkv, mp4 or mov
no_border = yes                      # hide the title bar while recording
keep_above = yes                     # keep the window on top while recording
restore_after = yes                  # give both back when done

## Your presets
[preset.mine]                        # listed first when you pick
window = 21:9
video  = 2560x1080

srec checks every line. An unknown setting, a bad value or a broken preset gives a warning with the line number, and srec uses the default for that value, so a typo never stops a recording.

• ENCODER=auto uses the NVIDIA GPU encoder when it works, which leaves the CPU free for the app.
• ffmpeg drops a few frames (about 5 to 20) while it starts. After that, the dropped count turns yellow if more frames are lost, and the speed turns yellow below 0.95x.
• With no audio, the file has no audio track at all.

• KDE Plasma on X11 only. Wayland and other desktops are not supported yet.
• Two windows of the same app with the same title are both resized.
• A minimized window is restored first, because X11 cannot record a minimized window.
• Check that nothing private is visible before you record.

One bash script. A KWin script (sent over D-Bus) resizes the window inside the screen's free area. ffmpeg x11grab -window_id records the window, and PulseAudio/PipeWire records the sound.

Similar tools: FFmpeg-Screen-Recorder (pads the video to 16:9 instead of resizing the window), shellrec, bashcaster. For a full GUI, use OBS Studio.

MIT