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();

        }

    }

}