private static List <Rect> GetBelowHorizontalFlagRect(Rect belowFlgRect, Bitmap image)
{
List <Rect> result = new List <Rect>();
Rect rect;
bool[,] marker = new bool[image.Width, image.Height];
int y = belowFlgRect.GetCenterPoint().y;
int x = belowFlgRect.GetCenterPoint().x;
int totalFlgRect = Constant.BELOW_HORIZONTAL_FLAG_RECT;
Point p;
while (result.Count < totalFlgRect)
{
p = new Point(x, y);
if (!p.IsValidPoint())
{
throw new Exception(ErrorUtils.getError(ErrorUtils.CAN_NOT_GET_ENOUGH_HORIZONTAL_FLAG_RECT, "Can not get enough horizontal flag rect!!"));
}
if (!marker[x, y] && CommonImageProcessing.IsBlackColor(new Point(x, y), image))
{
rect = CommonImageProcessing.ExpandTheRectBlackPixel(new Point(x, y), image, ref marker);
if (rect == null)
{
throw new Exception(ErrorUtils.getError(ErrorUtils.CAN_NOT_GET_ENOUGH_HORIZONTAL_FLAG_RECT, "Can not get enough horizontal flag rect!!"));
}
if (CommonImageProcessing.IsFlagRectangle(rect))
{
result.Add(rect);
}
}
x--;
}
return(result);
}
private static Rect DetectBottomRightCorner(Bitmap image)
{
var marker = new bool[image.Width, image.Height];
Point p = CommonImageProcessing.FindDifferentColorPoint(new Point(Constant.AS_RIGHT_BORDER, Constant.AS_BOTTOM_BORDER), image, Constant.WHITE, ref marker);
Rect bottomRightRect = CommonImageProcessing.ExpandTheRectBlackPixel(p, image, ref marker);
if (bottomRightRect == null)
{
p = CommonImageProcessing.FindDifferentColorPoint(new Point(Constant.AS_RIGHT_BORDER, Constant.AS_BOTTOM_BORDER), image, Constant.WHITE, ref marker);
bottomRightRect = CommonImageProcessing.ExpandTheRectBlackPixel(p, image, ref marker);
if (bottomRightRect == null)
{
throw new Exception(ErrorUtils.getError(ErrorUtils.CAN_NOT_FIND_THE_TOP_RIGHT_FLAG_RECT, "Can not detect the top right flag rectangle. Tried 2 attempts!!"));
}
else
{
ValidateBottomRightFlagRect(bottomRightRect);
return(bottomRightRect);
}
}
else
{
ValidateBottomRightFlagRect(bottomRightRect);
return(bottomRightRect);
}
}
private static Rect DetectTopRightFlagRect(Bitmap image)
{
//In case the points expanded not match the template rectangle. We need to mark the visited point, so we don't go to these point again
var marker = new bool[image.Width, image.Height];
Point p = CommonImageProcessing.FindDifferentColorPoint(new Point(Constant.AS_RIGHT_BORDER, Constant.AS_TOP_BORDER), image, Constant.WHITE, ref marker);
Rect topRightFlagRect = CommonImageProcessing.ExpandTheRectBlackPixel(p, image, ref marker);
if (topRightFlagRect == null)
{
p = CommonImageProcessing.FindDifferentColorPoint(new Point(Constant.AS_RIGHT_BORDER, Constant.AS_TOP_BORDER), image, Constant.WHITE, ref marker);
topRightFlagRect = CommonImageProcessing.ExpandTheRectBlackPixel(p, image, ref marker);
if (topRightFlagRect == null)
{
throw new Exception(ErrorUtils.getError(ErrorUtils.CAN_NOT_FIND_THE_TOP_RIGHT_FLAG_RECT, "Can not detect the top right flag rectangle. Tried 2 attempts!!"));
}
else
{
ValidateTopRightFlagRect(topRightFlagRect);
return(topRightFlagRect);
}
}
else
{
ValidateTopRightFlagRect(topRightFlagRect);
return(topRightFlagRect);
}
}
private static List <Rect> GetVerticalFlagRect(Rect aboveFlgRect, Bitmap image)
{
List <Rect> result = new List <Rect>();
Rect rect;
bool[,] marker = new bool[image.Width, image.Height];
int y = aboveFlgRect.GetCenterPoint().y;
int x = aboveFlgRect.GetCenterPoint().x;
int totalFlgRect = TemplateUtils.GetNumberOfVerticalFLagRect(Globals.currentTemplate);
Point p;
while (result.Count < totalFlgRect)
{
p = new Point(x, y);
if (!p.IsValidPoint())
{
throw new Exception(ErrorUtils.getError(ErrorUtils.CAN_NOT_GET_ENOUGH_VERTICAL_FLAG_RECT, "Can not get enough vertical flag rect!!"));
}
if (!marker[x, y] && CommonImageProcessing.IsBlackColor(new Point(x, y), image))
{
rect = CommonImageProcessing.ExpandTheRectBlackPixel(new Point(x, y), image, ref marker);
if (rect == null)
{
throw new Exception(ErrorUtils.getError(ErrorUtils.CAN_NOT_GET_ENOUGH_VERTICAL_FLAG_RECT, "Can not get enough vertical flag rect!!"));
}
if (CommonImageProcessing.IsFlagRectangle(rect))
{
result.Add(rect);
}
}
y++;
}
return(result);
}
private static Tuple <String, List <Circle> > DetectExamCode(Bitmap img, List <Rect> horizontalFlgRects, List <Rect> verticalFlgRects)
{
string examId = "";
List <Circle> lstCircles = new List <Circle>();
Circle c;
bool found;
for (int i = 1; i < 4; i++)
{
found = false;
for (int j = 1; j < 11; j++)
{
Rect r1 = horizontalFlgRects[i];
Rect r2 = verticalFlgRects[j];
Point c1 = r1.GetCenterPoint();
Point c2 = r2.GetCenterPoint();
c = new Circle(new Point(c1.x, c2.y), Constant.DEFAULT_CIRCLE_RADIUS);
int nOfBlackInCircle = CommonImageProcessing.CountNumberOfBlackPixelInCircle(img, c, -5);
if (nOfBlackInCircle >= Constant.NUMBER_OF_CIRCLE_BLACK_PIXEL_TO_BE_CONSIDERED_INFO_AS_CHOOSEN)
{
if (found)
{
examId = "-";
}
else
{
found = true;
if (examId != "-")
{
examId = (j - 1).ToString() + examId;
}
}
lstCircles.Add(c);
}
}
if (!found)
{
examId = examId + "*";
}
}
return(new Tuple <string, List <Circle> >(examId, lstCircles));
}
private static Bitmap PreProcess(Bitmap img)
{
i++;
//img.Save(@"D:\hello.jpg");
img = CommonImageProcessing.SmoothImage(img);
//img.Save(@"D:\hello_smooth.jpg");
img = CommonImageProcessing.ConvertToBinary(img);
img.Save(@"D:\hello_smooth_black1.jpg");
Rect topRightRect = DetectTopRightFlagRect(img);
Rect bottomRightRect = DetectBottomRightCorner(img);
double angle = calculateRotateAngle(topRightRect, bottomRightRect);
if (Math.Abs(topRightRect.bottomRight.x - bottomRightRect.bottomRight.x) > Constant.ACCEPTABLE_DIFF_BETWEEN_TOP_RIGHT_FLG_RECT_AND_BOTTOM_RIGHT_FLG_RECT)
{
img = CommonImageProcessing.RotateImage(img, angle - 90);
}
img.Save(@"D:\" + i + ".jpg");
return(img);
}
public static ProcessedAS ProcessAS(Bitmap img)
{
if (img.Width != Constant.AS_WIDTH || img.Height != Constant.AS_HEIGHT)
{
img = CommonImageProcessing.ResizeImage(img, Constant.AS_WIDTH, Constant.AS_HEIGHT);
}
Bitmap orgImg = img;
img = PreProcess(img);
Rect topRightRect = DetectTopRightFlagRect(img);
Rect bottomRightRect = DetectBottomRightCorner(img);
List <Rect> verticalFlagRects = GetVerticalFlagRect(topRightRect, img);
List <Rect> aboveHorizontalFlagRects = GetAboveHorizontalFlagRect(topRightRect, img);
List <Rect> belowHorizontalFlagRects = GetBelowHorizontalFlagRect(bottomRightRect, img);
Tuple <String, List <Circle> > studentCodeResult = DetectStudentCode(img, belowHorizontalFlagRects, verticalFlagRects);
Tuple <String, List <Circle> > examCodeResult = DetectExamCode(img, belowHorizontalFlagRects, verticalFlagRects);
Tuple <List <Char>, List <Circle>, List <Point> > studentAnswersResult = DetectStudentAnswer(img, aboveHorizontalFlagRects, verticalFlagRects);
String examId = examCodeResult.Item1;
String studentId = studentCodeResult.Item1;
ProcessedAS processedAS = new ProcessedAS();
processedAS.examId = examId;
processedAS.studentId = studentId;
StudentAnswer studentAnswer;
int numberOfQuestion = Globals.numberOfQuestion;
List <Char> answerText = studentAnswersResult.Item1;
List <Point> positions = studentAnswersResult.Item3;
List <StudentAnswer> studentAnswers = new List <StudentAnswer>();
for (int i = 1; i <= numberOfQuestion; i++)
{
Point p = positions[i];
// 300 x 38
// CvInvoke.Rectangle(outputImg, rect, new MCvScalar(255, 0, 255), 2);
studentAnswer = new StudentAnswer(answerText[i], new Point(p.x - 45, p.y - 18));
studentAnswers.Add(studentAnswer);
}
processedAS.answers = studentAnswers;
//List<Circle> tmp;
//tmp = studentCodeResult.Item2;
//Image<Bgr, Byte> outputImg = new Image<Bgr, Byte>(img);
//foreach (Circle circle in tmp)
//{
// CvInvoke.Circle(outputImg, new System.Drawing.Point(circle.center.x, circle.center.y), circle.radius - 2, new MCvScalar(0, 255, 0), 2);
//}
//tmp = examCodeResult.Item2;
//foreach (Circle circle in tmp)
//{
// CvInvoke.Circle(outputImg, new System.Drawing.Point(circle.center.x, circle.center.y), circle.radius - 2, new MCvScalar(0, 255, 0), 2);
//}
//tmp = studentAnswersResult.Item2;
//foreach (Circle circle in tmp)
//{
// CvInvoke.Circle(outputImg, new System.Drawing.Point(circle.center.x, circle.center.y), circle.radius-2, new MCvScalar(0, 255, 0), 2);
//}
processedAS.processedAnswerSheetImage = orgImg;
return(processedAS);
}
private static Tuple <List <Char>, List <Circle>, List <Point> > DetectStudentAnswer(Bitmap img, List <Rect> horizontalFlgRects, List <Rect> verticalFlgRects)
{
int numberOfQuestion = Globals.numberOfQuestion;
List <Char> answers = new List <Char>();
List <Circle> lstCircles = new List <Circle>();
List <Point> borderPoints = new List <Point>();
for (int i = 0; i < numberOfQuestion + 1; i++)
{
answers.Add('*');
borderPoints.Add(new Point(-100, -100));
}
int nHorizontalRect = horizontalFlgRects.Count;
int nVerticalRect = verticalFlgRects.Count;
Char currentAns = 'A';
int currentQuestion;
int colStartQuestion = 1;
int numberOfRow = (nVerticalRect - 12);
Circle c;
for (int i = nHorizontalRect - 1; i >= 1; i--)
{
currentQuestion = colStartQuestion;
for (int j = 11; j < nVerticalRect - 1; j++)
{
if (currentQuestion > numberOfQuestion)
{
break;
}
Rect r1 = horizontalFlgRects[i];
Rect r2 = verticalFlgRects[j];
Point c1 = r1.GetCenterPoint();
Point c2 = r2.GetCenterPoint();
if (currentAns == 'A')
{
borderPoints[currentQuestion] = new Point(c1.x, c2.y);
}
c = new Circle(new Point(c1.x, c2.y), Constant.DEFAULT_CIRCLE_RADIUS);
int nOfBlackInCircle = CommonImageProcessing.CountNumberOfBlackPixelInCircle(img, c, 8);
if (nOfBlackInCircle >= Constant.NUMBER_OF_CIRCLE_BLACK_PIXEL_TO_BE_CONSIDERED_ANSWER_AS_CHOOSEN)
{
if (answers[currentQuestion] == '*')
{
answers[currentQuestion] = currentAns;
}
else
{
answers[currentQuestion] = '-';
}
lstCircles.Add(c);
}
currentQuestion++;
if (currentQuestion > numberOfQuestion)
{
break;
}
}
if (currentAns == 'E')
{
currentAns = 'A';
colStartQuestion += numberOfRow;
}
else
{
currentAns++;
}
}
return(new Tuple <List <char>, List <Circle>, List <Point> >(answers, lstCircles, borderPoints));
}