Form1.cs

using System;
using System.Drawing;
rmusing System.Drawing.Imaging;
using System.Windows.Forms;

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

        private void button2_Click(object sender, EventArgs e)
        {
            CreateOffScreenBitmap();
        }

        private void CreateOffScreenBitmap()
        {
            Console.WriteLine("Create bitmap: width={0} height={1}", Width, Height);

            Bitmap offScreenBitmap = new Bitmap(Width, Height, PixelFormat.Format16bppRgb555);
            Graphics graphics = Graphics.FromImage(offScreenBitmap);

            Console.WriteLine("Done!");
        }
    }
}

Form1.Designer.cs

namespace GraphicsTestApp
{
    partial class Form1
    {
        /// <summary>
        /// Required designer variable.
        /// </summary>
        private System.ComponentModel.IContainer components = null;

        /// <summary>
        /// Clean up any resources being used.
        /// </summary>
        /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
        protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose();
            }
            base.Dispose(disposing);
        }

        #region Windows Form Designer generated code

        /// <summary>
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// </summary>
        private void InitializeComponent()
        {
            this.button2 = new System.Windows.Forms.Button();
            this.SuspendLayout();
            //
            // button2
            //
            this.button2.Location = new System.Drawing.Point(12, 12);
            this.button2.Name = "button2";
            this.button2.Size = new System.Drawing.Size(75, 23);
            this.button2.TabIndex = 1;
            this.button2.Text = "start";
            this.button2.UseVisualStyleBackColor = true;
            this.button2.Click += new System.EventHandler(this.button2_Click);
            //
            // Form1
            //
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(347, 159);
            this.Controls.Add(this.button2);
            this.Name = "Form1";
            this.Text = "Graphics Test App";
            this.ResumeLayout(false);

        }

        #endregion
        private System.Windows.Forms.Button button2;
    }
}

Program.cs

using System;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace GraphicsTestApp
{
    static class Program
    {
        /// <summary>
        /// The main entry point for the application.
        /// </summary>
        [STAThread]
        static void Main()
        {
            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);
            Application.Run(new Form1());
        }
    }
}