ImageGrab Module (macOS and Windows only)¶
- doc
https://pillow.readthedocs.io/en/latest/reference/ImageGrab.html, http://effbot.org/imagingbook/imagegrab.htm
Functions¶
grab¶
Note
For now, this function can’t grab windows that are layered on top of your window (popups, tooltips, menus, and more) on Windows. See issue#2569.
This example does so-called “record desktop” or “screen cast” (using PyAV):
#! /bin/env python
import time
import signal
import argparse
import json
from multiprocessing import Process, Queue
from Queue import Empty
import av # https://github.com/mikeboers/PyAV
from PIL import ImageGrab
def _run_capture(args, q):
def _IntHandler(signum, frame):
q.put("done")
signal.signal(signal.SIGINT, _IntHandler)
bbox = json.loads(args.bbox) if args.bbox else None
ocont = av.open(args.recordfile, "w")
vstream = None
vrate = 24 #
print("start capturing.")
while True:
dimg = ImageGrab.grab(bbox=bbox)
#dimg = dimg.resize((dimg.width // 4 * 3, dimg.height // 4 * 3))
if vstream is None:
vstream = ocont.add_stream('h264', rate=vrate)
vstream.width = dimg.width
vstream.height = dimg.height
vstream.pix_fmt = 'yuv420p'
vframe = av.VideoFrame.from_image(dimg)
for p in vstream.encode(vframe):
ocont.mux(p)
try:
r = q.get(block=False, timeout=1.0 // vrate)
if r:
break
except Empty as e:
pass
try:
for p in vstream.encode():
ocont.mux(p)
except av.AVError as e: # End Of File
pass
print("done.")
ocont.close() # MUST!
if __name__ == '__main__':
parser = argparse.ArgumentParser()
parser.add_argument(
"--bbox", type=str,
help="for example, --bbox='[0, 0, 1280, 769]'")
parser.add_argument("--recordfile", default="recorded.mp4")
parser.add_argument(
"--countdown",
help="countdown for starting, in secs.", type=float, default=0.5)
args = parser.parse_args()
time.sleep(args.countdown)
q = Queue()
p = Process(target=_run_capture, args=(args, q,))
p.start()
p.join()
To stop this script, press Ctrl-C.
grabclipboard¶
Note
When using old Pillow (ex. 2.9.0) on recent Windows (ex. Windows 7), this function doesn’t work. Upgrade Pillow!
This example grabs the image in the clipboard when you press “ALT + [PRNT SCRN]”.
For monitoring keyboard inputs, this example uses pynput.
This example is basically for Windows (because of keyboard.Key.print_screen), but
I think it’s easy to modify this for your platform.
#
# NOTE:
# Please stop running other capturing applications like 'DropBox' before
# running this demonstration.
#
from PIL import Image, ImageGrab
# pynput: https://pypi.python.org/pypi/pynput
# pynput allows you to control and monitor input devices.
from pynput import keyboard
class KC(object):
def __init__(self):
self._alt_pressed = False
self._count = 0
def on_press(self, key):
if not self._alt_pressed and (
key == keyboard.Key.alt_l or
key == keyboard.Key.alt_r):
self._alt_pressed = True
def on_release(self, key):
if key == keyboard.Key.print_screen and self._alt_pressed:
# NOTE: old Pillow can't deal with 'BMP bitfields layout'
# of recent Windows. Update Pillow.
img = ImageGrab.grabclipboard()
if img and not isinstance(img, (list, )):
#img.show()
img.save("captured%04d.png" % self._count)
self._count += 1
elif key == keyboard.Key.alt_l or key == keyboard.Key.alt_r:
self._alt_pressed = False
elif key == keyboard.Key.esc:
# Stop listener
return False
if __name__ == '__main__':
kc = KC()
with keyboard.Listener(
on_press=kc.on_press,
on_release=kc.on_release) as listener:
listener.join()
Using PyAV, you can directly encode these images to movie like this:
#! /bin/env python
#
# NOTE:
# Please stop running other capturing applications like 'DropBox' before
# running this demonstration.
#
from __future__ import division
import sys
import logging
from PIL import Image
from PIL import ImageGrab
from PIL import ImageOps
# pynput: https://pypi.python.org/pypi/pynput
# pynput allows you to control and monitor input devices.
from pynput import keyboard
import av # https://github.com/mikeboers/PyAV
class CaptureTask(object):
def __init__(self, args):
from math import ceil
from fractions import gcd
self._alt_pressed = False
logging.debug(args)
self._container = av.open(args.recordfile, "w")
_gcd = gcd(args.duration_per_shot, 1000)
framerate = 1000 // _gcd
self._repeat = int(ceil(args.duration_per_shot / _gcd))
logging.info("framerate={}, repeat={}".format(
framerate, self._repeat))
self._vstream = self._container.add_stream(
'h264', rate=framerate)
self._vstream.width = 1280
self._vstream.height = 768
self._vstream.pix_fmt = 'yuv420p'
def on_press(self, key):
if not self._alt_pressed and (
key == keyboard.Key.alt_l or
key == keyboard.Key.alt_r):
self._alt_pressed = True
def on_release(self, key):
if key == keyboard.Key.print_screen and self._alt_pressed:
# NOTE: old Pillow can't deal with 'BMP bitfields layout'
# of recent Windows. Update Pillow.
img = ImageGrab.grabclipboard()
if img and not isinstance(img, (list, )):
dimg = ImageOps.expand(
img,
border=((self._vstream.width - img.width) // 2,
(self._vstream.height - img.height) // 2))
vframe = av.VideoFrame.from_image(dimg)
logging.debug(vframe)
for i in range(self._repeat):
for p in self._vstream.encode(vframe):
logging.debug(p)
self._container.mux(p)
elif key == keyboard.Key.alt_l or key == keyboard.Key.alt_r:
self._alt_pressed = False
elif key == keyboard.Key.esc:
try:
# flush the rest in queue.
for p in self._vstream.encode():
logging.debug(p)
self._container.mux(p)
except av.AVError as e: # End Of File
pass
self._container.close() # MUST!
# Stop listener
return False
if __name__ == '__main__':
import argparse
parser = argparse.ArgumentParser()
parser.add_argument("--recordfile", default="prntscrns.mp4")
parser.add_argument("--duration-per-shot", help="in millisecs", type=int, default=1000)
parser.add_argument("--verbose", action="store_true")
args = parser.parse_args()
logging.basicConfig(
stream=sys.stderr,
level=logging.DEBUG if args.verbose else logging.INFO)
ct = CaptureTask(args)
with keyboard.Listener(
on_press=ct.on_press,
on_release=ct.on_release) as listener:
listener.join()