 |
Course CVCis: Computer Vision with C#
Chapter C4: The Complete Code of the Simple Recognition Project
Copyright © by V. Miszalok, last update: 2011-09-13
|
Main Menu after start of VC# 2010 Express: File -> New Project... -> Visual Studio installed templates: Windows Forms Application
Name: simple_recogn1 -> Location: C:\temp -> Create directory for solution: switch off -> OK
Delete two superfluous files: Form1.Designer.cs and Program.cs.
Replace the preprogrammed code of Form1.cs by:
using System;
using System.Drawing;
using System.Windows.Forms;
using System.Collections;
public class Form1 : Form
{ [STAThread] static void Main() { Application.Run( new Form1() ); }
const Int32 xSize = 11;
const Int32 ySize = 12;
Byte[,] i0 = new Byte[ySize ,xSize ];
Byte[,] c1v = new Byte[ySize ,xSize+1];
Brush[] brush = new Brush[10];
Brush blackbrush = SystemBrushes.ControlText;
Brush redbrush = new SolidBrush( Color.Red );
Brush bluebrush = new SolidBrush( Color.Blue );
Pen redpen = new Pen( Color.Red, 5 );
Pen whitepen;
Font arial10 = new Font( "Arial", 10 );
Font arial20 = new Font( "Arial", 20 );
Int32 i, x, y, dx, dy;
Byte threshold = 1;
Button[] button = new Button[ySize];
Point p0, p1, start = new Point();
ArrayList all_crackcodes = new ArrayList();
struct crackcode
{ public Byte no;
public Point start;
public String cracks;
public Int32 perimeter, area, xmin, xmax, ymin, ymax;
}
Int32 recogn_result;
Graphics g;
ArrayList pointArray = new ArrayList();
public Form1()
{ BackColor = Color.White;
Text = "Simple Numeral Recognition";
SetStyle( ControlStyles.ResizeRedraw, true );
Width = 800;
Height = 600;
for ( i=0; i < 10; i++ )
brush[i] = new SolidBrush( Color.FromArgb( i*25, i*25, i*25 ) );
for ( y=0; y < ySize; y++ )
{ button[y] = new Button();
Controls.Add( button[y] );
button[y].BackColor = Color.Gray;
button[y].Text = "nothing";
button[y].Name = y.ToString();
button[y].Click += new EventHandler( do_it );
}
button[0].Name = button[0].Text = "Digitize";
button[1].Name = button[1].Text = "Crack Code 8";
button[2].Name = button[2].Text = "Recognize";
button[3].Name = "Threshold";
button[4].Name = button[4].Text = "Noise";
button[5].Name = button[5].Text = "Clear";
button[3].Text = String.Format( "Threshold={0:#}", threshold );
}
protected override void OnPaint( PaintEventArgs e )
{ g = e.Graphics;
String s;
Rectangle r = ClientRectangle;
dx = r.Width / (xSize+2);
dy = ( r.Height - 2 * FontHeight ) / ySize;
for ( y=0; y < ySize; y++ )
{ button[y].Top = y*dy+1;
button[y].Left = xSize*dx+1;
button[y].Width = r.Width - button[y].Left - 2;
button[y].Height = dy-2;
}
for ( y=0; y < ySize; y++ )
for ( x=0; x < xSize; x++ )
g.FillRectangle( brush[i0[y,x]], x*dx, y*dy, dx, dy );
if ( all_crackcodes.Count == 0 )
{ s = "Draw a 0,1,2,..9 -> Digitize -> Crack Code 8 -> Recognize !";
g.DrawString( s, arial10, redbrush, (xSize*dx)/4, 0 );
return;
}
for ( i=0; i < all_crackcodes.Count; i++ )
{ crackcode c = (crackcode)all_crackcodes[i];
x = c.start.X;
y = c.start.Y;
for ( Int32 ii = 0; ii < c.perimeter; ii++ )
switch ( c.cracks[ii] )
{ case 'e': g.DrawLine( redpen, x*dx, y*dy, (x+1)*dx, y*dy ); x++; break;
case 's': g.DrawLine( redpen, x*dx, y*dy, x*dx, (y+1)*dy ); y++; break;
case 'w': g.DrawLine( redpen, x*dx, y*dy, (x-1)*dx, y*dy ); x--; break;
case 'n': g.DrawLine( redpen, x*dx, y*dy, x*dx, (y-1)*dy ); y--; break;
}
g.FillRectangle( bluebrush, x*dx-5, y*dy-5, 11, 11 );
if ( recogn_result >= 0 ) s = "This is a " + recogn_result.ToString() + ".";
else s = "I don't know what it is.";
g.DrawString( s, arial20, redbrush, 0, button[ySize-1].Top + button[ySize-1].Height + 2 );
}
}
protected override void OnMouseDown( MouseEventArgs e )
{ p0.X = e.X;
p0.Y = e.Y;
pointArray.Add( p0 );
whitepen = new Pen( Color.White, dx > dy ? dx : dy );
whitepen.StartCap = whitepen.EndCap = System.Drawing.Drawing2D.LineCap.Round;
}
protected override void OnMouseMove( MouseEventArgs e )
{ if ( e.Button == MouseButtons.None ) return;
p1.X = e.X;
p1.Y = e.Y;
//Insert an additional point if the distance is too far
if ( Math.Abs( p1.X - p0.X ) >= dx || Math.Abs( p1.Y - p0.Y ) >= dy )
pointArray.Add( new Point( (p1.X + p0.X)/2, (p1.Y + p0.Y)/2 ) );
pointArray.Add( p1 );
g = this.CreateGraphics();
g.DrawLine( whitepen, p0, p1 );
p0 = p1;
}
protected void do_it( object sender, System.EventArgs e )
{ switch( ((Button)sender).Name)
{ case "Digitize"://***********************************
i0 = new Byte[ySize,xSize];
for ( i = 0; i < pointArray.Count; i++ )
{ Point vertex = (Point)pointArray[i];
x = vertex.X / dx;
y = vertex.Y / dy;
try { if ( i0[y,x] < 9 ) i0[y,x]++; } catch{};
}
all_crackcodes.Clear(); recogn_result = -1; break;
case "Threshold"://*************************************
if ( ++threshold > 9 ) threshold = 1;
button[3].Text = "Threshold=" + threshold.ToString();
all_crackcodes.Clear(); recogn_result = -1; break;
case "Noise"://****************************************
Random random = new Random();
for ( y=0; y < ySize; y++ )
for ( x=0; x < xSize; x++ )
{ Int32 noise = random.Next() % 3 - 1;//gives -1 or 0 or +1
noise += i0[y,x];//add former gray value
if (noise < 0) i0[y,x] = 0;
else if (noise > 9) i0[y,x] = 9;
else i0[y,x] = (Byte)noise;
}
all_crackcodes.Clear(); recogn_result = -1; break;
case "Clear"://*******************************************
for ( y=0; y < ySize; y++ )
for ( x=0; x < xSize; x++ ) i0[y,x] = 0;
threshold = 1; button[3].Text = "Threshold=1";
all_crackcodes.Clear(); pointArray.Clear(); recogn_result = -1; break;
case "Crack Code 8": crackcode_finder(); break;
case "Recognize":
if ( all_crackcodes.Count == 0 ) { recogn_result = -1; Invalidate(); break; }
ArrayList shape_crackcodes = new ArrayList();
Int32 area = 0, index_biggest_cc = 0;
for ( i=0; i < all_crackcodes.Count; i++ )
{ crackcode c = (crackcode)all_crackcodes[i];
if ( c.area > area ) { area = c.area; index_biggest_cc = i; }
}
shape_crackcodes.Add(all_crackcodes[index_biggest_cc]);
for ( i=0; i < all_crackcodes.Count; i++ )
{ crackcode c = (crackcode)all_crackcodes[i];
if ( c.area < 0 )
{ Int32 count = 0;
for ( x=c.start.X+1; x < xSize; x++ )
if ( c1v[c.start.Y,x] == index_biggest_cc+1 ) count++;
if ( count%2 == 1 ) shape_crackcodes.Add( all_crackcodes[i] );
}
}
all_crackcodes.Clear();
for ( i=0; i < shape_crackcodes.Count; i++ )
all_crackcodes.Add( shape_crackcodes[i] );
shape_crackcodes.Clear();
if ( all_crackcodes.Count > 3 ) { recogn_result = -1; break; }
if ( all_crackcodes.Count == 3 ) { recogn_result = 8; break; }
crackcode cc = (crackcode)all_crackcodes[0];
if ( all_crackcodes.Count == 2 )
{ crackcode ci = (crackcode)all_crackcodes[1];
Single sdx = (Single)(cc.xmax+cc.xmin)/2.0f - (Single)(ci.xmax+ci.xmin)/2.0f;
Single sdy = (Single)(cc.ymax+cc.ymin)/2.0f - (Single)(ci.ymax+ci.ymin)/2.0f;
Single distance = (Single)Math.Sqrt( sdx*sdx - sdy*sdy );
if ( distance < (cc.ymax-cc.ymin)/5.0f ) { recogn_result = 0; break; }
if ( sdy < 0.0f ) recogn_result = 6; else recogn_result = 9; break;
}
//one crack code only
if ( (cc.ymax-cc.ymin) > 3*(cc.xmax-cc.xmin) ) { recogn_result = 1; break; }
Single thickness_top=0, thickness_mid=0, thickness_bottom=0;
Int32 one_third = (3*cc.ymin + cc.ymax-cc.ymin)/3;
Int32 two_third = (3*one_third + cc.ymax-cc.ymin)/3;
Int32 left=0, right=0, n_top=0, n_mid=0, n_bottom=0;
for ( y=cc.ymin; y < cc.ymax; y++ )
{ for ( x=cc.xmin; x < cc.xmax; x++ )
if ( c1v[y,x] == cc.no ) { left = x; break; }
for ( x=cc.xmax; x >= cc.xmin; x-- )
if ( c1v[y,x] == cc.no ) { right = x; break; }
if ( y < one_third ) { thickness_top += right-left; n_top++; } else
if ( y <= two_third ) { thickness_mid += right-left; n_mid++; } else
{ thickness_bottom += right-left; n_bottom++;};
}
if ( n_top <= 0 || n_mid <= 0 || n_bottom <= 0 ) { recogn_result = -1; break; }
thickness_top /= n_top;
thickness_mid /= n_mid;
thickness_bottom /= n_bottom;
if ( thickness_bottom < 2f )
if ( thickness_top > thickness_mid ) { recogn_result = 7; break; }
else { recogn_result = 4; break; }
if ( thickness_mid < 2f ) { recogn_result = 2; break; }
//The following decision between 3 and 5 is based on vector graphics !
//When both start & end points are at the left side -> 3 otherwise -> 5
Int32 startx = ((Point)pointArray[0]).X;
Int32 endx = ((Point)pointArray[pointArray.Count-1]).X;
Int32 minx = startx, maxx = startx;
for ( i=1; i < pointArray.Count; i++ )
{ if ( ((Point)pointArray[i]).X < minx ) minx = ((Point)pointArray[i]).X;
if ( ((Point)pointArray[i]).X > maxx ) maxx = ((Point)pointArray[i]).X;
}
if ( Math.Abs(endx-startx) < (maxx-minx)/3 )
{ recogn_result = 3; break; }
else
{ recogn_result = 5; break; }
} // end of cases, end of switch
Invalidate();
} // end of protected void do_it( object sender, System.EventArgs e )
private void crackcode_finder()
{ all_crackcodes.Clear();
for ( y=0; y < ySize; y++ )
for ( x=0; x <= xSize; x++ ) c1v[y,x] = 0;
start.X = start.Y = 0;
for ( Byte cc_no = 1; start_crack_search(); cc_no++ )
{ crackcode cc = new crackcode();
System.Text.StringBuilder cracks = new System.Text.StringBuilder();
cc.start = start; cracks.Append('s'); cc.area = 0; cc.no = cc_no;
x = cc.xmin = cc.xmax = start.X;
cc.ymin = start.Y;
y = cc.ymax = start.Y+1;
Char last_crack = 's';
do
{ switch ( last_crack )
{ case 'e': if ( x == xSize ) goto n;
if ( y < ySize && i0[y ,x ] >= threshold) goto s;
if ( i0[y-1,x ] >= threshold) goto e; goto n;
case 's': if ( y == ySize ) goto e;
if ( x > 0 && i0[y ,x-1] >= threshold) goto w;
if ( i0[y ,x ] >= threshold) goto s; goto e;
case 'w': if ( x == 0 ) goto s;
if ( y > 0 && i0[y-1,x-1] >= threshold) goto n;
if ( i0[y ,x-1] >= threshold) goto w; goto s;
case 'n': if ( y == 0 ) goto w;
if ( x < xSize && i0[y-1,x ] >= threshold) goto e;
if ( i0[y-1,x-1] >= threshold) goto n; goto w;
}
e: last_crack = 'e'; cracks.Append( 'e' ); x++; cc.area += y;
if ( x > cc.xmax) cc.xmax = x; continue;
s: last_crack = 's'; cracks.Append( 's' ); y++; c1v[y-1,x] = cc_no;
if ( y > cc.ymax) cc.ymax = y; continue;
w: last_crack = 'w'; cracks.Append( 'w' ); x--; cc.area -= y;
if ( x < cc.xmin ) cc.xmin = x; continue;
n: last_crack = 'n'; cracks.Append( 'n' ); y--; c1v[y ,x] = cc_no;
if ( y < cc.ymin ) cc.ymin = y; continue;
} while ( x != start.X || y != start.Y ); //end of do
cc.cracks = cracks.ToString();
cc.perimeter = cc.cracks.Length;
all_crackcodes.Add( cc );
} // end of for
}
private Boolean start_crack_search()
{ Byte left;
for ( y=start.Y; y < ySize; y++ )
for ( x=0; x < xSize; x++ )
{ if ( x > 0 ) left = i0[y,x-1]; else left = 0;
if ( left < threshold && i0[y,x] >= threshold && c1v[y,x] == 0 )
{ start.X = x; start.Y = y; c1v[y,x] = 1; return true; }
}
return false;
}
}
 |