save image in different bitdepth matlab in javascript

main.m
% Load an image in MATLAB.
img = imread('example.jpg');

% Convert the image to grayscale.
grayImg = rgb2gray(img);

% Save the image in 8-bit grayscale.
imwrite(grayImg, 'example_8bit_grayscale.jpg', 'BitDepth', 8);

% Save the image in 16-bit grayscale.
imwrite(grayImg, 'example_16bit_grayscale.png', 'BitDepth', 16);
321 chars
12 lines

index.tsx
// Load an image in JavaScript.
var img = new Image();
img.src = 'example.jpg';

// Wait for the image to load.
img.addEventListener('load', function() {
  // Create a canvas element.
  var canvas = document.createElement('canvas');
  canvas.width = img.width;
  canvas.height = img.height;

  // Draw the image on the canvas element.
  var ctx = canvas.getContext('2d');
  ctx.drawImage(img, 0, 0);

  // Get the image data from the canvas.
  var imageData = ctx.getImageData(0, 0, canvas.width, canvas.height);

  // Create a new canvas element for the output image.
  var outputCanvas = document.createElement('canvas');
  outputCanvas.width = canvas.width;
  outputCanvas.height = canvas.height;

  // Draw the image data on the output canvas with 8-bit depth.
  var outputCtx = outputCanvas.getContext('2d');
  outputCtx.putImageData(imageData, 0, 0, 0, 0, canvas.width, canvas.height);
  outputCtx.drawImage(outputCanvas, 0, 0, canvas.width, canvas.height);

  // Save the 8-bit image.
  var link = document.createElement('a');
  link.download = 'example_8bit.png';
  link.href = outputCanvas.toDataURL('image/png');
  link.click();

  // Draw the image data on the output canvas with 16-bit depth.
  var outputCtx2 = outputCanvas.getContext('2d', {alpha: false});
  var imageData16 = Uint16Array.from(imageData.data);

  for (var i=0; i<imageData.data.length; i+=4) {
    var pixelValue = imageData.data[i];
    imageData16[i/4] = pixelValue * (65535/255);
  }

  imageData.data.set(new Uint8ClampedArray(imageData16.buffer));
  outputCtx2.putImageData(imageData, 0, 0, 0, 0, canvas.width, canvas.height);
  outputCtx2.drawImage(outputCanvas, 0, 0, canvas.width, canvas.height);

  // Save the 16-bit image.
  link.download = 'example_16bit.png';
  link.href = outputCanvas.toDataURL('image/png');
  link.click();
});
1825 chars
53 lines