ponty / pyscreenshot

Python screenshot library, replacement for the Pillow ImageGrab module on Linux.
BSD 2-Clause "Simplified" License
499 stars 89 forks source link

TL;DR: Use Pillow. If Pillow doesn't work or it's slow then try pyscreenshot.

The pyscreenshot module is obsolete in most cases. It was created because PIL ImageGrab module worked on Windows only, but now Linux and macOS are also supported by Pillow. There are some features in pyscreenshot which can be useful in special cases: flexible backends with the same interface, Wayland support, sometimes better performance, optional subprocessing.

The module can be used to copy the contents of the screen to a Pillow image memory using various back-ends. Replacement for the ImageGrab Module.

For handling image memory (e.g. saving to file, converting,..) please read Pillow documentation.

Links:

workflow

Goal: Pyscreenshot tries to allow to take screenshots without installing 3rd party libraries. It is cross-platform. It is only a pure Python wrapper, a thin layer over existing back-ends. Its strategy should work on most Linux distributions: a lot of back-ends are wrapped, if at least one exists then it works, if not then one back-end should be installed.

Features:

Known problems:

Comparison:

system pyscreenshot 3.1 pillow 9.4.0 mss 7.0.1
Ubuntu 22.04
Kubuntu 22.04
Xubuntu 22.04
Lubuntu 22.04
Ubuntu Server 22.04+sway+grim

Installation:

$ python3 -m pip install Pillow pyscreenshot

Examples

# pyscreenshot/examples/grabfullscreen.py

"Grab the whole screen"
import pyscreenshot as ImageGrab

# grab fullscreen
im = ImageGrab.grab()

# save image file
im.save("fullscreen.png")
# pyscreenshot/examples/grabbox.py

"Grab the part of the screen"
import pyscreenshot as ImageGrab

# part of the screen
im = ImageGrab.grab(bbox=(10, 10, 510, 510))  # X1,Y1,X2,Y2

# save image file
im.save("box.png")
# pyscreenshot/examples/virtdisp.py

"Create screenshot of xmessage with Xvfb"
from time import sleep

from easyprocess import EasyProcess
from pyvirtualdisplay import Display

import pyscreenshot as ImageGrab

with Display(size=(100, 60)) as disp:  # start Xvfb display
    # display is available
    with EasyProcess(["xmessage", "hello"]):  # start xmessage
        sleep(1)  # wait for displaying window
        img = ImageGrab.grab()
img.save("xmessage.png")

Image:

Performance

The performance can be checked with pyscreenshot.check.speedtest module. Backends are started in a subprocess with default (safest) settings which is necessary to isolate them from the main process and from each other. Disabling this option makes performance much better, but it may cause problems in some cases.

Test on Ubuntu 22.04 X11

Versions:

$ python3 -m pyscreenshot.check.versions
python               3.10.6
pyscreenshot         3.1
pil                  9.0.1
mss                  7.0.1
scrot                1.7
grim                 ?.?
maim                 5.6.3
imagemagick          6.9.11
pyqt5                5.15.6
pyside2              5.15.2
wx                   4.0.7
pygdk3               3.42.1
mac_screencapture    
mac_quartz           
freedesktop_dbus     ?.?
gnome_dbus           ?.?
gnome-screenshot     41.0

Backends are started in a subprocess (safest):

$ python3 -m pyscreenshot.check.speedtest

n=10
------------------------------------------------------
default                 1    sec    (  100 ms per call)
pil                     1.7  sec    (  167 ms per call)
mss                     2    sec    (  197 ms per call)
scrot                   1    sec    (  100 ms per call)
grim                    
maim                    1.4  sec    (  135 ms per call)
imagemagick             2.2  sec    (  221 ms per call)
pyqt5                   4    sec    (  403 ms per call)
pyside2                 3.9  sec    (  394 ms per call)
wx                      2.9  sec    (  293 ms per call)
pygdk3                  2.2  sec    (  218 ms per call)
mac_screencapture       
mac_quartz              
gnome_dbus              
gnome-screenshot        4    sec    (  401 ms per call)

Backends are started without subprocess (fastest):

$ python3 -m pyscreenshot.check.speedtest --childprocess 0

n=10
------------------------------------------------------
default                 0.13 sec    (   12 ms per call)
pil                     0.12 sec    (   11 ms per call)
mss                     0.2  sec    (   19 ms per call)
scrot                   1    sec    (   99 ms per call)
grim                    
maim                    1.3  sec    (  134 ms per call)
imagemagick             2.2  sec    (  218 ms per call)
pyqt5                   1    sec    (  104 ms per call)
pyside2                 1    sec    (  101 ms per call)
wx                      0.34 sec    (   33 ms per call)
pygdk3                  0.23 sec    (   23 ms per call)
mac_screencapture       
mac_quartz              
gnome_dbus              
gnome-screenshot        4.4  sec    (  437 ms per call)

You can force a backend:

import pyscreenshot as ImageGrab
im = ImageGrab.grab(backend="scrot")

You can force if subprocess is applied, setting it to False together with mss or pil gives the best performance in most cases:

# best performance
import pyscreenshot as ImageGrab
im = ImageGrab.grab(backend="mss", childprocess=False)

Wayland

Wayland is supported with these setups:

  1. using D-Bus (org.freedesktop.portal.Screenshot) on any desktop with xdg-desktop-portal.
  2. using D-Bus (org.gnome.Shell.Screenshot) on GNOME.
  3. using Grim on any Wayland compositor with wlr-screencopy-unstable-v1 support. (GNOME:no, KDE:no, Sway:yes)

If both Wayland and X are available then Wayland is preferred because Xwayland can not be used for screenshot. Rules for decision:

  1. use X if DISPLAY variable exists and XDG_SESSION_TYPE variable != "wayland"
  2. use Wayland if 1. is not successful

Dependencies

Only pure python modules are used:

  1. EasyProcess for calling programs
  2. entrypoint2 for generating command line interface
  3. MSS backend is added because it is very fast and pure and multiplatform
  4. jeepney for D-Bus calls

Test

Some Linux distributions can be tested with VirtualBox and Vagrant:

$ ./tests/vagrant/vagrant_boxes.py

Hierarchy

Alt text