How to convert a bitmap photo to Hexadecimal color codes?

问题

I'm trying to create a program for my resume But I have a problem with converting bitmap photo that is greyscale photo to hexadecimal or better calls it the codes if the colors are anyone who can help me?

I tried to convert it with base64string but it didn't work.

openFileDialog1=new OpenFileDialog();
OpenFileDialog dlg = new OpenFileDialog();

dlg.Title = "Open Image";
dlg.Filter = "bmp files (*.bmp)|*.bmp";

if (dlg.ShowDialog() == DialogResult.OK)
{
     Rectangle bounds = Screen.GetBounds(Point.Empty);
     Bitmap bitmap = new Bitmap(bounds.Width, bounds.Height);

using (Graphics g = Graphics.FromImage(bitmap))
{
     g.CopyFromScreen(Point.Empty, Point.Empty, bounds.Size);
}

// Convert the image to byte[]
System.IO.MemoryStream stream = new System.IO.MemoryStream();
bitmap.Save(stream, System.Drawing.Imaging.ImageFormat.Bmp);
byte[] imageBytes = stream.ToArray();

// Convert byte[] to Base64 String
string base64String = Convert.ToBase64String(imageBytes);

// Write the bytes (as a Base64 string) to the textbox
textBox1.Text = base64String.ToString();

I expected to see a bunch of numbers like A9C or 255 but the thing that I saw is nothing.

回答1:

It works with .bmp files as in your code and gives AARRGGBB codes of pixels.

using System;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Windows.Forms;

namespace WindowsFormsApp2
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            using (OpenFileDialog dlg = new OpenFileDialog())
            {
                dlg.Title = "Open Image";
                dlg.Filter = "bmp files (*.bmp)|*.bmp";

                if (dlg.ShowDialog() == DialogResult.OK)
                {
                    var colorCodes = this.GetColorCodes(dlg.FileName);
                    var str = string.Join(Environment.NewLine,
                                          colorCodes.Select<int[], string>(line => string.Join(" ", line.Select<int, string>(code => string.Format("{0:X8}", code))))); // string.Format("{0:X6}", code & 0x00FFFFFF) if you want RRGGBB format
                    textBox1.Text = str; // requires textBox1.Multiline = true, better have monospaced font
                }
            }
        }

        private int[][] GetColorCodes(string path)
        {
            var bitmap = new Bitmap(path);
            return Enumerable.Range(0, bitmap.Height)
                             .Select<int, int[]>(y => Enumerable.Range(0, bitmap.Width)
                                                    .Select<int, int>(x => bitmap.GetPixel(x, y).ToArgb())
                                                    .ToArray())
                             .ToArray();
        }
    }
}

来源：https://stackoverflow.com/questions/55656218/how-to-convert-a-bitmap-photo-to-hexadecimal-color-codes

标签

hex

bmp

converters