Tried to fix the offset between clicks and the actual zone but its still not perfect. And you can delete the zones

TestVideo/Extraction.cs

@@ -73,26 +73,35 @@ namespace TestVideo
         }
         public void RemoveZone(int idZone)
         {
-            Zones.RemoveAt(idZone);
+            if (Zones.Count > idZone)
+                Zones.RemoveAt(idZone);
         }
 
         public Rectangle GetZoneArea(int idZone)
         {
-            return Zones[idZone].ZoneArea;
+            if (Zones.Count > idZone)
+                return Zones[idZone].ZoneArea;
+            return new Rectangle(new Point(0,0),new Size(0, 0));
         }
 
         public Bitmap GetZoneData(int idZone)
         {
-            return Zones[idZone].ZoneData;
+            if (Zones.Count > idZone)
+                return Zones[idZone].ZoneData;
+            return new Bitmap(1,1);
         }
 
         public string GetZoneRawText(int idZone)
         {
-            return Zones[idZone].RawText;
+            if(Zones.Count > idZone)
+                return Zones[idZone].RawText;
+            return "";
         }
         public string[] GetZonesCleanText(int idZone)
         {
-            return Zones[idZone].CleanText;
+            if (Zones.Count > idZone)
+                return Zones[idZone].CleanText;
+            return new string[] { "" };
         }
         private Bitmap ScreenShot()
         {
@@ -116,7 +125,7 @@ namespace TestVideo
             {
                 foreach (Zone zone in Zones)
                 {
-                    g.DrawRectangle(new Pen(Color.Red,3),zone.ZoneArea);
+                    g.DrawRectangle(new Pen(Color.Green,3),zone.ZoneArea);
                 }
             }
         }

TestVideo/Form1.Designer.cs

@@ -37,7 +37,7 @@
             this.tbxResult = new System.Windows.Forms.TextBox();
             this.lsbZones = new System.Windows.Forms.ListBox();
             this.btnCreateZone = new System.Windows.Forms.Button();
-            this.button2 = new System.Windows.Forms.Button();
+            this.btnDeleteZone = new System.Windows.Forms.Button();
             this.lsbZoneTypes = new System.Windows.Forms.ListBox();
             this.label1 = new System.Windows.Forms.Label();
             this.label2 = new System.Windows.Forms.Label();
@@ -121,14 +121,15 @@
             this.btnCreateZone.UseVisualStyleBackColor = true;
             this.btnCreateZone.Click += new System.EventHandler(this.btnCreateZone_Click);
             // 
-            // button2
+            // btnDeleteZone
             // 
-            this.button2.Location = new System.Drawing.Point(978, 453);
+            this.btnDeleteZone.Location = new System.Drawing.Point(978, 453);
-            this.button2.Name = "button2";
+            this.btnDeleteZone.Name = "btnDeleteZone";
-            this.button2.Size = new System.Drawing.Size(482, 37);
+            this.btnDeleteZone.Size = new System.Drawing.Size(482, 37);
-            this.button2.TabIndex = 7;
+            this.btnDeleteZone.TabIndex = 7;
-            this.button2.Text = "Delete Zone";
+            this.btnDeleteZone.Text = "Delete Zone";
-            this.button2.UseVisualStyleBackColor = true;
+            this.btnDeleteZone.UseVisualStyleBackColor = true;
+            this.btnDeleteZone.Click += new System.EventHandler(this.btnDeleteZone_Click);
             // 
             // lsbZoneTypes
             // 
@@ -195,7 +196,7 @@
             this.Controls.Add(this.label2);
             this.Controls.Add(this.label1);
             this.Controls.Add(this.lsbZoneTypes);
-            this.Controls.Add(this.button2);
+            this.Controls.Add(this.btnDeleteZone);
             this.Controls.Add(this.btnCreateZone);
             this.Controls.Add(this.lsbZones);
             this.Controls.Add(this.tbxResult);
@@ -222,7 +223,7 @@
         private System.Windows.Forms.TextBox tbxResult;
         private System.Windows.Forms.ListBox lsbZones;
         private System.Windows.Forms.Button btnCreateZone;
-        private System.Windows.Forms.Button button2;
+        private System.Windows.Forms.Button btnDeleteZone;
         private System.Windows.Forms.ListBox lsbZoneTypes;
         private System.Windows.Forms.Label label1;
         private System.Windows.Forms.Label label2;

TestVideo/Form1.cs

@@ -12,6 +12,7 @@ using Emgu.CV;
 using Emgu.CV.OCR;
 using Emgu.CV.Structure;
 using System.IO;
+using System.Runtime.InteropServices;
 
 namespace TestVideo
 {
@@ -29,6 +30,8 @@ namespace TestVideo
         public Form1()
         {
             InitializeComponent();
+            SetDpiAwareness();
+
             screens = Screen.AllScreens;
             extraction = new Extraction(screens[0]);
             currentZoneIndex = -1;
@@ -97,10 +100,13 @@ namespace TestVideo
             if (creatingZone)
             {
                 //Convert coordinates to image coordinates
-                Rectangle screenSize = extraction.CurrentScreen.Bounds;
+                
-                float xRatio = (float)screenSize.Width / (float)pbxInput.Width;
+                //Rectangle screenSize = extraction.CurrentScreen.Bounds;
-                float yRatio = (float)screenSize.Height / (float)pbxInput.Height;
+                float xRatio = (float)pbxInput.Image.Width / (float)pbxInput.Width;
+                float yRatio = (float)pbxInput.Image.Height / (float)pbxInput.Height;
                 Point tmpPoint = pbxInput.PointToClient(MousePosition);
+                //MouseEventArgs me = (MouseEventArgs)e;
+                //Point tmpPoint = me.Location;
                 Point newPoint = new Point(Convert.ToInt32((float)tmpPoint.X * xRatio),Convert.ToInt32((float)tmpPoint.Y * yRatio));
 
                 if (newZonePoints[0] == new Point(-1,-1))
@@ -148,5 +154,40 @@ namespace TestVideo
                 currentZoneIndex = lsbZones.SelectedIndex;
             }
         }
+
+        private void btnDeleteZone_Click(object sender, EventArgs e)
+        {
+            if (lsbZones.SelectedIndex != -1)
+                extraction.RemoveZone(lsbZones.SelectedIndex);
+            RefreshUi();
+        }
+
+        //ProcessDPIAwarness, SetProcessDpiAwarness and SetDpi Awarness are not coded by me 
+        //They have been found on stack overflow https://stackoverflow.com/questions/27987085/screen-resolution-not-matching-screen-bounds
+        //To fix a problem where Screen.Bounds returned false values
+        //You use it just by callinf SetDpiAwarness() before calling Screen.Bounds
+        private enum ProcessDPIAwareness
+        {
+            ProcessDPIUnaware = 0,
+            ProcessSystemDPIAware = 1,
+            ProcessPerMonitorDPIAware = 2
+        }
+
+        [DllImport("shcore.dll")]
+        private static extern int SetProcessDpiAwareness(ProcessDPIAwareness value);
+
+        private static void SetDpiAwareness()
+        {
+            try
+            {
+                if (Environment.OSVersion.Version.Major >= 6)
+                {
+                    SetProcessDpiAwareness(ProcessDPIAwareness.ProcessPerMonitorDPIAware);
+                }
+            }
+            catch (EntryPointNotFoundException)//this exception occures if OS does not implement this API, just ignore it.
+            {
+            }
+        }
     }
 }