코랩(Colab) Camera Capture

@notepad_jj2

츄르사려고 코딩하는집사입니다.

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1. colab.research.google.com 사이트에 왼쪽 Sider bar <> 기호를 눌러 Camera Capture의 오른쪽 화살표 표시를 누른다.

 

2. 카메라 캡처를 하려면 총 4개의 코드를 돌려야 한다.

1) 카메라 캡처에 필요한 라이브러리 import 및 카메라 캡처 함수

from IPython.display import display, Javascript
from google.colab.output import eval_js
from base64 import b64decode

def take_photo(filename='photo.jpg', quality=0.8):
  js = Javascript('''
    async function takePhoto(quality) {
      const div = document.createElement('div');
      const capture = document.createElement('button');
      capture.textContent = 'Capture';
      div.appendChild(capture);

      const video = document.createElement('video');
      video.style.display = 'block';
      const stream = await navigator.mediaDevices.getUserMedia({video: true});

      document.body.appendChild(div);
      div.appendChild(video);
      video.srcObject = stream;
      await video.play();

      // Resize the output to fit the video element.
      google.colab.output.setIframeHeight(document.documentElement.scrollHeight, true);

      // Wait for Capture to be clicked.
      await new Promise((resolve) => capture.onclick = resolve);

      const canvas = document.createElement('canvas');
      canvas.width = video.videoWidth;
      canvas.height = video.videoHeight;
      canvas.getContext('2d').drawImage(video, 0, 0);
      stream.getVideoTracks()[0].stop();
      div.remove();
      return canvas.toDataURL('image/jpeg', quality);
    }
    ''')
  display(js)
  data = eval_js('takePhoto({})'.format(quality))
  binary = b64decode(data.split(',')[1])
  with open(filename, 'wb') as f:
    f.write(binary)
  return filename

 

2) 카메라 캡처 함수를 실행시켜 카메라 캡처 기능과 캡처한 사진 출력

from IPython.display import Image
try:
  filename = take_photo()
  print('Saved to {}'.format(filename))
  
  # Show the image which was just taken.
  display(Image(filename))
except Exception as err:
  # Errors will be thrown if the user does not have a webcam or if they do not
  # grant the page permission to access it.
  print(str(err))

 

아래의 사진처럼 캡처한 결과가 출력된다.

 

3) openCV 라이브러리를 이용한 imgshow

from google.colab.patches import cv2_imshow

!curl -o logo.png https://colab.research.google.com/img/colab_favicon_256px.png
import cv2
img = cv2.imread('logo.png', cv2.IMREAD_UNCHANGED)
cv2_imshow(img)