获取数组中的周围像素

function getSurroundingPixels(array, row, col) {
  var surroundingPixels = [];
  
  // 检查上方像素
  if (row > 0) {
    surroundingPixels.push(array[row - 1][col]);
  }
  
  // 检查下方像素
  if (row < array.length - 1) {
    surroundingPixels.push(array[row + 1][col]);
  }
  
  // 检查左侧像素
  if (col > 0) {
    surroundingPixels.push(array[row][col - 1]);
  }
  
  // 检查右侧像素
  if (col < array[row].length - 1) {
    surroundingPixels.push(array[row][col + 1]);
  }
  
  return surroundingPixels;
}

// 示例用法
var pixelArray = [
  [1, 2, 3],
  [4, 5, 6],
  [7, 8, 9]
];

var surroundingPixels = getSurroundingPixels(pixelArray, 1, 1);
console.log(surroundingPixels); // 输出 [2, 4, 6, 8]