ERROR: Could not initialize SDL video: No available video device

[hamadzidani]

• I have read the FAQ.
• I have searched in existing issues.

Environment

• OS: Debian
• scrcpy version: [e.g. 1.12.1]
• installation method: Tried manual build, apt, snap
• device model: Samsung A04
• Android version: 13

Describe the bug

scrcpy 2.1.1 <https://github.com/Genymobile/scrcpy>
ERROR: Could not initialize SDL video: No available video device
ERROR: Could not start adb server

I have installed all the prerequisites as required from the Readme.MD, additionally, I installed dev libraries of x11 and Xorg
The command scrcpy --version shows

scrcpy 2.1.1 <https://github.com/Genymobile/scrcpy>

Dependencies (compiled / linked):
 - SDL: 2.0.22 / 2.0.22
 - libavcodec: 58.134.100 / 58.134.100
 - libavformat: 58.76.100 / 58.76.100
 - libavutil: 56.70.100 / 56.70.100
 - libavdevice: 58.13.100 / 58.13.100
 - libusb: - / 1.0.25

I have set scrcpy --display=0 because scrcpy --list-displays shows

scrcpy 2.1.1 <https://github.com/Genymobile/scrcpy>
INFO: ADB device found:
INFO:     -->   (usb)  R9WTA085GCE                     device  SM_A045F
/usr/local/share/scrcpy/scrcpy-server: 1 file pushed. 3.2 MB/s (56995 bytes in 0.017s)
[server] INFO: List of displays:
    --display=0    (720x1600)

I also exported with export SDL_VIDEODRIVER=x11 which again the same error occurred

scrcpy 2.1.1 <https://github.com/Genymobile/scrcpy>
ERROR: Could not initialize SDL video: x11 not available
ERROR: Could not start adb server

Not sure if this has anything to do with adb but adb --version is

Android Debug Bridge version 1.0.41
Version 28.0.2-debian
Installed as /usr/lib/android-sdk/platform-tools/adb

and adb devices

List of devices attached
R9WTA085GCE	device

I tried also over tcpip.

[rom1v]

From which graphical environment do you start scrcpy?

[hamadzidani]

From which graphical environment do you start scrcpy?

from Guake Terminal. I also start scrcpy from the desktop entry of docker applications. By the way, the Ubuntu flavor I'm running is called POP!_OS. And it was running a few months ago, I doubt some libraries might be updated or removed and then reinstalled under other versions. I remember I was installed Android Studio then I removed it along with Gradle and other SDKs.

[rom1v]

echo $XDG_SESSION_TYPE

[hamadzidani]

echo $XDG_SESSION_TYPE returns x11.

[rom1v]

OK, and:

echo $DISPLAY

[hamadzidani]

echo $DISPLAY returns :1

[rom1v]

Is it correct?

export DISPLAY=:0
scrcpy

Does it work better?

[hamadzidani]

unfortunately not. Tried with

export DISPLAY=:0
scrcpy

returns the same error

scrcpy 2.1.1 <https://github.com/Genymobile/scrcpy>
ERROR: Could not initialize SDL: No available video device
ERROR: Could not start adb daemon

Then tried with

export DISPLAY=:1
scrcpy

The same error keeps throwing.

[hamadzidani]

scrcpy --list-displays
scrcpy 2.1.1 <https://github.com/Genymobile/scrcpy>
INFO: ADB device found:
INFO:     --> (tcpip)  192.168.1.4:5555                device  SM_A045F
/usr/local/share/scrcpy/scrcpy-server: 1 file pushed. 1.2 MB/s (56995 bytes in 0.044s)
[server] INFO: List of displays:
    --display=0    (720x1600)

--display=0 means the Android interface display while

echo $DISPLAY
:1

is the display of the Linux system, right?

[rom1v]

Yes, --display= is the Android display.

Install xeyes, then run:

DISPLAY=:0 xeyes
DISPLAY=:1 xeyes

Does it work?

[hamadzidani]

the first command says Error: Can't open display: :0 while the latter one opens a small window that has eyes dynamic drawing following the mouse despite the display index being 0 for scrcpy.
If I understand this correctly, something odd with scrcpy which is not setting :1 as the default display.

I couldn't change the display id of scrcpy using scrcpy --display 1 because the previous command scrcpy --list-displays still shows --display=0 (720x1600).

[rom1v]

while the latter one opens a small window that has eyes dynamic drawing following the mouse

OK, so DISPLAY=:1 is correct.

Forget about scrcpy --display=, this has nothing to do with your X11 display (it's when you plug an external monitor on your Android device or when you configure a virtual display).

Create a file sample.c and compile it:

#include <SDL2/SDL.h>

int main(void) {
    if (SDL_Init(SDL_INIT_VIDEO) == -1) {
        fprintf(stderr, "SDL error: %s\n", SDL_GetError());
        return 1;
    }

    SDL_Quit();

    printf("ok\n");
    return 0;
}

Compile it:

gcc sample.c -lSDL -o sample

And run it:

./sample

What is the result?

[hamadzidani]

SDL error: No available video device as expected; one should find how to change the default x server to 0 instead of 1

[rom1v]

How did you install SDL2? Are you sure it is compiled with x11 support?

[hamadzidani]

sudo apt install libsdl2-2.0-0 and libsdl2-dev. I followed this answer and the first comment by recompiling SDL2 from the source code. After that, I encountered an Audio driver problem but resolved it with export SDL_AUDIODRIVER=dummy.

[UPDATE]:

I made a mistake by exporting: SDL_AUDIODRIVER=dummy (dummy has no sound output; as a muted audio driver); instead, one should export:
export SDL_AUDIODRIVER=alsa for Linux. But this should work only if ./configure detects alsa as an audio driver:
Audio drivers : disk dummy oss alsa(dynamic)
If alsa wasn't there, then one should install its dev libraries using sudo apt install libasound2-dev
Then proceed to:

./configure
make
sudo make install

to recompile the SDL from the source code.