切掉图片白边.js

gistfile1.txt

// write by openai chatgpt
const Jimp = require('jimp');

Jimp.read('./sample.jpg')
  .then((image) => {
    const width = image.bitmap.width;
    const height = image.bitmap.height;

    let left = 0;
    let top = 0;
    let right = width - 1;
    let bottom = height - 1;

    // Find left boundary
    for (let x = 0; x < width; x++) {
      let isEmptyColumn = true;
      for (let y = 0; y < height; y++) {
        const pixel = Jimp.intToRGBA(image.getPixelColor(x, y));
        if (pixel.r !== 255 || pixel.g !== 255 || pixel.b !== 255) {
          isEmptyColumn = false;
          break;
        }
      }
      if (!isEmptyColumn) {
        break;
      }
      left++;
    }

    // Find top boundary
    for (let y = 0; y < height; y++) {
      let isEmptyRow = true;
      for (let x = left; x <= right; x++) {
        const pixel = Jimp.intToRGBA(image.getPixelColor(x, y));
        if (pixel.r !== 255 || pixel.g !== 255 || pixel.b !== 255) {
          isEmptyRow = false;
          break;
        }
      }
      if (!isEmptyRow) {
        break;
      }
      top++;
    }

    // Find right boundary
    for (let x = width - 1; x >= left; x--) {
      let isEmptyColumn = true;
      for (let y = top; y <= bottom; y++) {
        const pixel = Jimp.intToRGBA(image.getPixelColor(x, y));
        if (pixel.r !== 255 || pixel.g !== 255 || pixel.b !== 255) {
          isEmptyColumn = false;
          break;
        }
      }
      if (!isEmptyColumn) {
        break;
      }
      right--;
    }

    // Find bottom boundary
    for (let y = height - 1; y >= top; y--) {
      let isEmptyRow = true;
      for (let x = left; x <= right; x++) {
        const pixel = Jimp.intToRGBA(image.getPixelColor(x, y));
        if (pixel.r !== 255 || pixel.g !== 255 || pixel.b !== 255) {
          isEmptyRow = false;
          break;
        }
      }
      if (!isEmptyRow) {
        break;
      }
      bottom--;
    }

    // Crop the image based on the boundaries
    image.crop(left, top, right - left + 1, bottom - top + 1);

    // Save the cropped image
    image.write('./output.jpg');
    console.log('Image cropped successfully!');
  })
  .catch((error) => {
    console.error('Error cropping image:', error);
  });