It splits two images from given image file.

split_jpg.cs

using System;
using System.Drawing;

namespace split_jpg {
  class Program {
    static void Main (string[] args) {
      try {
        string filename = args[0];
        Bitmap src = Image.FromFile(filename) as Bitmap;
        int split = 2;
        int width = src.Width / split;
        for (int i = 0; i < split; ++i) {
          int x = width * i;
          Rectangle crop = new Rectangle(x, 0, width, src.Height);
          Bitmap target = new Bitmap(crop.Width, crop.Height);
          using (Graphics g = Graphics.FromImage(target)) {
            g.DrawImage(src, new Rectangle(0, 0, crop.Width, crop.Height), crop, GraphicsUnit.Pixel);
          }
          target.Save(string.Format("{0}_{1}.jpg", filename, i + 1), System.Drawing.Imaging.ImageFormat.Jpeg);
        }
      } catch (Exception ex) {
        Console.WriteLine(ex.Message);
      }
    }
  }
}