path: root/README.md

![](https://dec05eba.com/images/gpu_screen_recorder_logo_small.png)

# GPU Screen Recorder
This is a screen recorder that has minimal impact on system performance by recording your monitor using the GPU only,
similar to shadowplay on windows. This is the fastest screen recording tool for Linux.

This screen recorder can be used for recording your desktop offline, for live streaming and for nvidia shadowplay-like instant replay,
where only the last few minutes are saved.

Supported video codecs:
* H264 (default on Intel)
* HEVC (default on AMD and NVIDIA)
* AV1 (not currently supported on NVIDIA if you use GPU Screen Recorder flatpak)

Supported audio codecs:
* Opus (default)
* AAC
* FLAC

## Note
This software works with x11 and wayland, but when using Wayland then only monitors can be recorded.
### TEMPORARY ISSUES
1) screen-direct capture has been temporary disabled as it causes issues with stuttering. This might be a nvfbc bug.
2) Videos are in variable framerate format. Use MPV to play such videos, otherwise you might experience stuttering in the video if you are using a buggy video player. You can try saving the video into a .mkv file instead as some software may have better support for .mkv files (such as kdenlive). You can use the "-fm cfr" option to to use constant framerate mode.
3) HDR capture is supported (on wayland), but all GPU drivers have bugs that ignore HDR metadata so the HDR metadata will be missing in the video file. I will eventually patch the video file to workaround these GPU driver issues.
4) Opus and FLAC audio codecs are disabled at the moment because of temporary issues.
### AMD/Intel/Wayland root permission
When recording a window under AMD/Intel no special user permission is required, however when recording a monitor (or when using wayland) the program needs root permission (to access KMS).\
To make this safer, the part that needs root access has been moved to its own executable (to make it as small as possible).\
For you as a user this only means that if you installed GPU Screen Recorder as a flatpak then a prompt asking for root password will show up when you start recording.
# Performance
On a system with a i5 4690k CPU and a GTX 1080 GPU:\
When recording Legend of Zelda Breath of the Wild at 4k, fps drops from 30 to 7 when using OBS Studio + nvenc, however when using this screen recorder the fps remains at 30.\
When recording GTA V at 4k on highest settings, fps drops from 60 to 23 when using obs-nvfbc + nvenc, however when using this screen recorder the fps only drops to 58. The quality is also much better when using gpu screen recorder.\
GPU Screen Recorder also produces much smoother videos than OBS when GPU utilization is close to 100%, see comparison here: [https://www.youtube.com/watch?v=zfj4sNVLLLg](https://www.youtube.com/watch?v=zfj4sNVLLLg).\
It is recommended to save the video to a SSD because of the large file size, which a slow HDD might not be fast enough to handle. Using variable framerate mode (-fm vfr) which is the default is also recommended as this reduces encoding load. Ultra quality is also overkill most of the time, very high (the default) or lower quality is usually enough.
## Note about optimal performance on NVIDIA
NVIDIA driver has a "feature" (read: bug) where it will downclock memory transfer rate when a program uses cuda (or nvenc, which uses cuda), such as GPU Screen Recorder. To work around this bug, GPU Screen Recorder can overclock your GPU memory transfer rate to it's normal optimal level.\
To enable overclocking for optimal performance use the `-oc` option when running GPU Screen Recorder. You also need to have "Coolbits" NVIDIA X setting set to "12" to enable overclocking. You can automatically add this option if you run `sudo nvidia-xconfig --cool-bits=12` and then reboot your computer.\
Note that this only works when Xorg server is running as root, and using this option will only give you a performance boost if the game you are recording is bottlenecked by your GPU.\
Note! use at your own risk!

# Installation
If you are running an Arch Linux based distro, then you can find gpu screen recorder on aur under the name gpu-screen-recorder-git (`yay -S gpu-screen-recorder-git`).\
If you are running another distro then you can run `sudo ./install.sh`, but you need to manually install the dependencies, as described below.\
You can also install gpu screen recorder ([the gtk gui version](https://git.dec05eba.com/gpu-screen-recorder-gtk/)) from [flathub](https://flathub.org/apps/details/com.dec05eba.gpu_screen_recorder), which is the easiest method
to install GPU Screen Recorder on non-arch based distros.\
The only official ways to install GPU Screen Recorder is either from source, AUR or flathub. If you install GPU Screen Recorder from somewhere else and have an issue then try installing it
from one of the official sources before reporting it as an issue.
If you install GPU Screen Recorder flatpak, which is the gtk gui version then you can still run GPU Screen Recorder command line by using the flatpak command option, for example `flatpak run --command=gpu-screen-recorder com.dec05eba.gpu_screen_recorder -w screen -f 60 -o video.mp4`. Note that if you want to record your monitor on AMD/Intel then you need to install the flatpak system-wide (like so: `flatpak install flathub --system com.dec05eba.gpu_screen_recorder`).

# Dependencies
## AMD
libglvnd (which provides libgl and libegl)\
mesa\
ffmpeg (libavcodec, libavformat, libavutil, libswresample, libavfilter)\
x11 (libx11, libxcomposite, libxrandr, xfixes)\
libpulse\
vaapi (libva, libva-mesa-driver)\
libdrm\
libcap\
wayland-client
## Intel
libglvnd (which provides libgl and libegl)\
mesa\
ffmpeg (libavcodec, libavformat, libavutil, libswresample, libavfilter)\
x11 (libx11, libxcomposite, libxrandr, xfixes)\
libpulse\
vaapi (libva, intel-media-driver/libva-intel-driver)\
libdrm\
libcap\
wayland-client
## NVIDIA
libglvnd (which provides libgl and libegl)\
ffmpeg (libavcodec, libavformat, libavutil, libswresample, libavfilter)\
x11 (libx11, libxcomposite, libxrandr, xfixes)\
libpulse\
cuda runtime (libcuda.so.1) (libnvidia-compute)\
nvenc (libnvidia-encode)\
libva\
libdrm\
libcap\
wayland-client\
nvfbc (libnvidia-fbc1, when recording the screen on x11)\
xnvctrl (libxnvctrl0, when using the `-oc` option)

# How to use
Run `gpu-screen-recorder --help` to see all options.
## Recording
Here is an example of how to record all monitors and the default audio output: `gpu-screen-recorder -w screen -f 60 -a "$(pactl get-default-sink).monitor" -o ~/Videos/test_video.mp4` then stop the screen recorder with `Ctrl+C`, which will also save the recording. You can record a single monitor if you change `-w screen` to the name of a monitor, which you can find if you run the `xrandr`. An example of a monitor name is HDMI-1.
## Streaming
Streaming works the same as recording, but the `-o` argument should be path to the live streaming service you want to use (including your live streaming key). Take a look at scripts/twitch-stream.sh to see an example of how to stream to twitch.
## Replay mode
Run `gpu-screen-recorder` with the `-c mp4` and `-r` option, for example: `gpu-screen-recorder -w screen -f 60 -r 30 -c mp4 -o ~/Videos`. Note that in this case, `-o` should point to a directory.\
If `-mf yes` is set, replays are save in folders based on the date.
To save a video in replay mode, you need to send signal SIGUSR1 to gpu screen recorder. You can do this by running `killall -SIGUSR1 gpu-screen-recorder`.\
To stop recording send SIGINT to gpu screen recorder. You can do this by running `killall -SIGINT gpu-screen-recorder` or pressing `Ctrl-C` in the terminal that runs gpu screen recorder.\
To pause/unpause recording send SIGUSR2 to gpu screen recorder. You can do this by running `killall -SIGUSR2 gpu-screen-recorder`. This is only applicable and useful when recording (not streaming nor replay).\
The file path to the saved replay is output to stdout. All other output from GPU Screen Recorder is output to stderr.\
The replay buffer is stored in ram (as encoded video), so don't use a too large replay time and/or video quality unless you have enough ram to store it.
## Finding audio device name
You can find the default output audio device (headset, speakers (in other words, desktop audio)) with the command `pactl get-default-sink`. Add `monitor` to the end of that to use that as an audio input in gpu screen recorder.\
You can find the default input audio device (microphone) with the command `pactl get-default-source`. This input should not have `monitor` added to the end when used in gpu screen recorder.\
Example of recording both desktop audio and microphone: `gpu-screen-recorder -w screen -f 60 -a "$(pactl get-default-sink).monitor" -a "$(pactl get-default-source)" -o ~/Videos/test_video.mp4`.\
A name (that is visible to pipewire) can be given to an audio input device by prefixing the audio input with `<name>/`, for example `dummy/$(pactl get-default-sink).monitor`.\
Note that if you use multiple audio inputs then they are each recorded into separate audio tracks in the video file. If you want to merge multiple audio inputs into one audio track then separate the audio inputs by "|" in one -a argument,
for example `-a "$(pactl get-default-sink).monitor|$(pactl get-default-source)"`.

There is also a gui for the gpu screen recorder called [gpu-screen-recorder-gtk](https://git.dec05eba.com/gpu-screen-recorder-gtk/).
## Simple way to run replay without gui
Run the script `scripts/start-replay.sh` to start replay and then `scripts/save-replay.sh` to save a replay and `scripts/stop-replay.sh` to stop the replay. The videos are saved to `$HOME/Videos`.
You can use these scripts to start replay at system startup if you add `scripts/start-replay.sh` to startup (this can be done differently depending on your desktop environment / window manager) and then go into
hotkey settings on your system and choose a hotkey to run the script `scripts/save-replay.sh`. Modify `scripts/start-replay.sh` if you want to use other replay options.
## Run replay on system startup
If you installed GPU Screen Recorder from AUR or from source and you are running a distro that uses systemd then you will have a systemd service installed that can be started with `systemctl enable --now --user gpu-screen-recorder`. This systemd service runs GPU Screen Recorder on system startup.\
It's configured with `$HOME/.config/gpu-screen-recorder.env` (create it if it doesn't exist). You can look at [extra/gpu-screen-recorder.env](https://git.dec05eba.com/gpu-screen-recorder/plain/extra/gpu-screen-recorder.env) to see an example.
You can see which variables that you can use in the `gpu-screen-recorder.env` file by looking at the `extra/gpu-screen-recorder.service` file. Note that all of the variables are optional, you only have to set the ones that are you interested in.
You can use the `scripts/save-replay.sh` script to save a replay and by default the systemd service saves videos in `$HOME/Videos`.\
If you are using a NVIDIA GPU then it's recommended to set PreserveVideoMemoryAllocations=1 as mentioned in the section below.
## Examples
Look at the [scripts](https://git.dec05eba.com/gpu-screen-recorder/tree/scripts) directory for script examples. For example if you want to automatically save a recording/replay into a folder with the same name as the game you are recording.
# Issues
## NVIDIA
Nvidia drivers have an issue where CUDA breaks if CUDA is running when suspend/hibernation happens, and it remains broken until you reload the nvidia driver. To fix this, either disable suspend or tell the NVIDIA driver to preserve video memory on suspend/hibernate by using the `NVreg_PreserveVideoMemoryAllocations=1` option. You can run `sudo extra/install_preserve_video_memory.sh` to automatically add that option to your system.

# Reporting bugs
Issues are reported on this Github page: [https://github.com/dec05eba/gpu-screen-recorder-issues/issues](https://github.com/dec05eba/gpu-screen-recorder-issues/issues)
# Contributing patches
See [https://git.dec05eba.com/?p=about](https://git.dec05eba.com/?p=about)

# Demo
[![Click here to watch a demo video on youtube](https://img.youtube.com/vi/n5tm0g01n6A/0.jpg)](https://www.youtube.com/watch?v=n5tm0g01n6A)

# FAQ
## How is this different from using OBS with nvenc?
OBS only uses the gpu for video encoding, but the window image that is encoded is copied from the GPU to the CPU and then back to the GPU (video encoding unit). These operations are very slow and causes all of the fps drops when using OBS. OBS only uses the GPU efficiently on Windows 10 and Nvidia.\
This gpu screen recorder keeps the window image on the GPU and sends it directly to the video encoding unit on the GPU by using CUDA. This means that CPU usage remains at around 0% when using this screen recorder.
## How is this different from using OBS NvFBC plugin?
The plugin does everything on the GPU and gives the texture to OBS, but OBS does not know how to use the texture directly on the GPU so it copies the texture to the CPU and then back to the GPU (video encoding unit). These operations are very slow and causes a lot of fps drops unless you have a fast CPU. This is especially noticable when recording at higher resolutions than 1080p.
## How is this different from using FFMPEG with x11grab and nvenc?
FFMPEG only uses the GPU with CUDA when doing transcoding from an input video to an output video, and not when recording the screen when using x11grab. So FFMPEG has the same fps drop issues that OBS has.
## It tells me that my AMD/Intel GPU is not supported or that my GPU doesn't support h264/hevc, but that's not true!
Some linux distros (such as manjaro and fedora) disable hardware accelerated h264/hevc on AMD/Intel because of "patent license issues". If you are using an arch-based distro then you can install mesa-git instead of mesa and if you are using another distro then you may have to switch to a better distro. On fedora based distros you can follow this: [Hardware Accelerated Codec](https://rpmfusion.org/Howto/Multimedia).\
If you installed GPU Screen Recorder flatpak then you can try installing mesa-extra freedesktop runtime by running this command: `flatpak install --system org.freedesktop.Platform.GL.default//23.08-extra`
## I have an old nvidia GPU that supports nvenc but I get a cuda error when trying to record
Newer ffmpeg versions don't support older nvidia cards. Try installing GPU Screen Recorder flatpak from [flathub](https://flathub.org/apps/details/com.dec05eba.gpu_screen_recorder) instead. It comes with an older ffmpeg version which might work for your GPU.
## I get a black screen/glitches while live streaming
It seems like ffmpeg earlier than version 6.1 has some type of bug. Install ffmpeg 6.1 and then reinstall GPU Screen Recorder to fix this issue. The flatpak version of GPU Screen Recorder comes with ffmpeg 6.1 so no extra steps are needed.
## I can't play the video in my browser directly or in discord
Browsers and discord don't support hevc video codec at the moment. Choose h264 video codec instead with the -k h264 option.
Note that websites such as youtube support hevc so there is no need to choose h264 video codec if you intend to upload the video to youtube or if you want to play the video locally or if you intend to
edit the video with a video editor. Hevc allows for better video quality (especially at lower file sizes) so hevc (or av1) is recommended for source videos.
## I get a black bar on the right/bottom in the video
This is mostly an issue on AMD. For av1 it's a hardware issue, see: https://gitlab.freedesktop.org/mesa/mesa/-/issues/9185. For hevc it's a software issue that has been fixed but not released yet, see: https://gitlab.freedesktop.org/mesa/mesa/-/issues/10985.
If you get black bars then the workaround is to record with h264 video codec instead (using the -k h264 option).
## The video is glitched, looks like checkerboard pattern
This is an issue on some intel integrated gpus on wayland caused by power saving option. Right now the only way to fix this is to record on X11 instead.
## The video doesn't display or has a green/yellow overlay
This can happen if your video player is missing the H264/HEVC video codecs. Either install the codecs or use mpv.
## I get stutter in the video
Try recording to an SSD and make sure it's not using NTFS file system. Also record in variable framerate format.
## I get a black screen when recording
This can happen if you use software such as prime-run to run GPU Screen Recorder. Such software should not be used to run GPU Screen Recorder.
GPU Screen Recorder needs to run on the same GPU that you use to display your monitors graphics to work.

# Donations
If you want to donate you can donate via bitcoin or monero.
* Bitcoin: bc1qqvuqnwrdyppf707ge27fqz2n9y9gu7lf5ypyuf
* Monero: 4An9kp2qW1C9Gah7ewv4JzcNFQ5TAX7ineGCqXWK6vQnhsGGcRpNgcn8r9EC3tMcgY7vqCKs3nSRXhejMHBaGvFdN2egYet

# TODO
* Dynamically change bitrate/resolution to match desired fps. This would be helpful when streaming for example, where the encode output speed also depends on upload speed to the streaming service.
* Implement opengl injection to capture texture. This fixes VRR without having to use NvFBC direct capture.
* Always use direct capture with NvFBC once the capture issue in mpv fullscreen has been resolved (maybe detect if direct capture fails in nvfbc and switch to non-direct recording. NvFBC says if direct capture fails).