/// <summary>
/// Get borders of meaning part of image
/// </summary>
/// <param name="angle">Skew angle of image</param>
/// <param name="completedWidth">Width to which the image was completed</param>
/// /// <param name="resultWidth">Width of result (deskewed) image</param>
/// <param name="resultHeight">Height of result (deskewed) image</param>
/// <param name="projectedImage">Projected image</param>
/// <param name="originalWidth">Width of original image</param>
/// <param name="originalHeight">Height of original image</param>
/// <returns>Rectangle which bounds meaning part of image</returns>
private static Rectangle GetImageBordersWithoutWhiteSpaces(double angle, int completedWidth, int resultWidth, int resultHeight, KrecImage projectedImage, int originalWidth, int originalHeight)
{
var smallImage = BitmapProcessor.RotateGrayscaleImage(projectedImage, -angle); // Для скорости, границы обрезки ищем на уменьшенном изображении
var smallBinary = BitmapProcessor.BinarizeGrayscaleImage(smallImage);
var cutBorders = ImagePartitioner.GetImageWithoutBorders(smallBinary);
var k = (double)originalWidth / completedWidth;
var preComplementWidth = (int)(originalWidth / k);
var preComplementHeight = (int)(originalHeight / k);
var scaleRect = GetUnprojectedRectangle(cutBorders, projectionSideWidth, projectionSideWidth,
preComplementWidth, preComplementHeight,
originalWidth, originalHeight, angle);
int scaleXError = resultWidth / projectionSideWidth; //Увеличиваем с учетом погрешности
int scaleYError = resultHeight / projectionSideWidth;
scaleRect.X = Math.Max(scaleRect.X - scaleXError, 0);
scaleRect.Y = Math.Max(scaleRect.Y - scaleYError, 0);
scaleRect.Width = Math.Min(scaleRect.Width + scaleXError, resultWidth - scaleRect.X);
scaleRect.Height = Math.Min(scaleRect.Height + scaleYError, resultHeight - scaleRect.Y);
return(scaleRect);
}
/// <summary>
/// Get angle to right image orientation (Multiples Pi/2, from -Pi/2 to Pi)
/// </summary>
/// <param name="image">Deskewed mage which nedd to be oriented</param>
/// <returns>Angle to right orientation</returns>
public static double GetAngleToRightOrientation(KrecImage image)
{
var binary = BitmapProcessor.BinarizeGrayscaleImage(image);
var result90 = Get90AngleToRightOrientation(binary, image.HorizontalResolution, image.VerticalResolution);
bool isCorrect90Oriented = result90.Item1;
var lines = result90.Item2.Lines;
// Not enough information to perform calculations of rotation angle
// All lines contains less than one char inside
if (lines.All(line => line.Chars.Length <= 1))
{
return(0);
}
if (!isCorrect90Oriented)
{
binary = RotateMatrixBy90(binary);
}
CleanUpBinaryFromNoise(binary, result90.Item2.BadChars);
var linesSum = GetBluredBoundingRectsSums(lines.Select(line => line.BoundingRect), binary);
double orientSum = 0;
for (var i = 0; i < linesSum.Count; ++i)
{
orientSum += GetLineOrientation(lines[i].BoundingRect, binary, linesSum[i], result90.Item2.MaxCharHeight);
}
double expectation = orientSum / linesSum.Count;
bool isCorrect180Oriented = (Math.Abs(expectation) < 0.011) || orientSum >= 0; //при мат. ожидании меньше 0.011 результаты данной оценки недостоверны, а статистически вероятнее всего изображение ориентировано правильно
if (!isCorrect180Oriented && !isCorrect90Oriented)
{
return(-Math.PI / 2);
}
if (!isCorrect180Oriented)
{
return(Math.PI);
}
if (!isCorrect90Oriented)
{
return(Math.PI / 2);
}
return(0);
}
/// <summary>
/// Initialize processor for grayscale image
/// </summary>
/// <param name="image">Grayscale image</param>
public RectanglesProcessor(KrecImage image)
: this(BitmapProcessor.BinarizeGrayscaleImage(image), image.VerticalResolution)
{
}
