In Linux on my Chromebook, I am trying to take a screenshot using the command line, but nothing seems to be working. I have tried ImageMagick...

sudo apt-get install imagemagick

import -window root filename.png
# "unable to read X window image 'root'"

import filename.png
# "unable to grab mouse '': No such file or directory"

And I have also tried scrot...

sudo apt-get install scrot

scrot -u filename.png
#"BadDrawable (invalid Pixmap or Window parameter)"

I tried several python methods, but the only one that I could successfully install and get to run without errors was pyscreeze (which uses scrot), and it produced nothing but a blank, black image, which is useless to me.

In terms of other python methods, I tried pyautogui which failed to install, telling me "Failed building wheel for Pillow." I tried pyscreenshot, which installed and ran but told me "All backends failed." I also tried ImageGrab, which told me "ImageGrab is MacOS and Windows only."

Does anyone know of a way to make this work?

Thanks in advance!

Javascript solution

Here is a way to take a screenshot of any part of the chromebook's screen, a chrome window, or a chrome tab.

Paste this into your browser console to take a screenshot.

async function takeScreenshot(format = "image/png") {
  const stream = await navigator.mediaDevices.getDisplayMedia({video:true});

  const video = document.createElement("video");
  video.srcObject = stream;
  video.muted = true;
  await video.play();

  const canvas = document.createElement("canvas");
  canvas.width = video.videoWidth;
  canvas.height = video.videoHeight;
  const context = canvas.getContext("2d");

  context.drawImage(video, 0, 0);

  const blob = await new Promise(resolve => canvas.toBlob(resolve, format));

  stream.getTracks().forEach(track => track.stop());

  return blob;
}

function download(blob, name = "Untitled") {
  const elt = document.createElement("a");
  elt.download = name;
  elt.href = URL.createObjectURL(blob);
  elt.click();
  URL.revokeObjectURL(elt.href);
}

takeScreenshot("image/png").then(blob => download(blob, "Screenshot.png"));