[R语言] BitmapToASCii

using System;
using System.Collections.Generic;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace PicToASCii
{
  public static class ASCiiHelper
  {
    public static string Generate(Bitmap bitmap, int rowSize, int colSize, int type)
    {
      StringBuilder result = new StringBuilder();
      char[] charset = { ' ', '.', ',', ':', ';', 'i', '1', 'r', 's', '5', '3', 'A', 'H', '9', '8', '&', '@', '#' };
      if (type == 1)
      {
        //charset = new char[] { '8', '9', '6', '4', '3', '5', '7', '0', '2', '1', '.',' ' };
        charset = new char[] { ' ', '.', '1', '2', '0', '7', '5', '3', '4', '6', '9', '8' };
      }
      else if (type == 2)
      {
        charset = new char[] { '丶', '卜', '乙', '日', '瓦', '車', '馬', '龠', '齱', '龖' };
      }
      int bitmapH = bitmap.Height;
      int bitmapW = bitmap.Width;
      for (int h = 0; h < bitmapH / rowSize; h++)
      {
        int offsetY = h * rowSize;
        for (int w = 0; w < bitmapW / colSize; w++)
        {
          int offsetX = w * colSize;
          float averBright = 0;
          for (int j = 0; j < rowSize; j++)
          {
            for (int i = 0; i < colSize; i++)
            {
              try
              {
                Color color = bitmap.GetPixel(offsetX + i, offsetY + j);
                averBright += color.GetBrightness();
              }
              catch (ArgumentOutOfRangeException)
              {
                averBright += 0;
              }
            }
          }
          averBright /= (rowSize * colSize);
          int index = (int)(averBright * charset.Length);
          if (index == charset.Length)
            index--;
          result.Append(charset[charset.Length - 1 - index]);
        }
        result.Append("\r\n");
      }
      return result.ToString();
    }
  }
}