Erosion operator from Mathematical Morphology.
The filter assigns minimum value of surrounding pixels to each pixel of the result image. Surrounding pixels, which should be processed, are specified by structuring element: 1 - to process the neighbor, -1 - to skip it.
The filter especially useful for binary image processing, where it removes pixels, which are not surrounded by specified amount of neighbors. It gives ability to remove noisy pixels (stand-alone pixels) or shrink objects.
For processing image with 3x3 structuring element, there are different optimizations available, like Erosion3x3 and BinaryErosion3x3.
The filter accepts 8 and 16 bpp grayscale images and 24 and 48 bpp color images for processing.
Sample usage:
// create filter Erosion filter = new Erosion( ); // apply the filter filter.Apply( image ); Initial image:
Result image:
private string reconhecerCaptcha(Image img)
{
Bitmap imagem = new Bitmap(img);
imagem = imagem.Clone(new Rectangle(0, 0, img.Width, img.Height), System.Drawing.Imaging.PixelFormat.Format24bppRgb);
Erosion erosion = new Erosion();
Dilatation dilatation = new Dilatation();
Invert inverter = new Invert();
ColorFiltering cor = new ColorFiltering();
cor.Blue = new AForge.IntRange(200, 255);
cor.Red = new AForge.IntRange(200, 255);
cor.Green = new AForge.IntRange(200, 255);
Opening open = new Opening();
BlobsFiltering bc = new BlobsFiltering();
Closing close = new Closing();
GaussianSharpen gs = new GaussianSharpen();
ContrastCorrection cc = new ContrastCorrection();
bc.MinHeight = 10;
FiltersSequence seq = new FiltersSequence(gs, inverter, open, inverter, bc, inverter, open, cc, cor, bc, inverter);
pictureBox.Image = seq.Apply(imagem);
string reconhecido = OCR((Bitmap)pictureBox.Image);
return reconhecido;
}
private void cBFilters_SelectedIndexChanged(object sender, EventArgs e)
{
Bitmap pictureTransform = (Bitmap)pbChoose.Image;
if ((string)cBFilters.SelectedItem == "HSL_Filter")
{
AForge.Imaging.Filters.SaturationCorrection filter = new SaturationCorrection(0.1);
Bitmap newImage = filter.Apply(pictureTransform);
pbChoose.SizeMode = PictureBoxSizeMode.CenterImage;
pBNew.Image = newImage;
}
if ((string)cBFilters.SelectedItem == "Mediana")
{
AForge.Imaging.Filters.Median filter = new Median();
Bitmap newImage = filter.Apply(pictureTransform);
pbChoose.SizeMode = PictureBoxSizeMode.CenterImage;
pBNew.Image = newImage;
}
/*if ((string)cBFilters.SelectedItem == "Fourier_Transformation")
{
Complex[] dst = new Complex[n];
AForge.Math.FourierTransform filter = AForge.Math.FourierTransform.DFT();// .FromBitmap(pictureTransform);
Bitmap newImage = filter.Apply();
pbChoose.SizeMode = PictureBoxSizeMode.CenterImage;
pBNew.Image = newImage;
}*/
if ((string)cBFilters.SelectedItem == "Binarization")
{
pictureTransform = Grayscale.CommonAlgorithms.BT709.Apply(pictureTransform);
Threshold threshold = new Threshold(127);
threshold.ApplyInPlace(pictureTransform);
pbChoose.SizeMode = PictureBoxSizeMode.CenterImage;
pBNew.Image = pictureTransform;
}
if ((string)cBFilters.SelectedItem == "Grayscale")
{
AForge.Imaging.Filters.Grayscale filter = new AForge.Imaging.Filters.Grayscale(0.2125, 0.7154, 0.0721);
Bitmap newImage = filter.Apply(pictureTransform);
pbChoose.SizeMode = PictureBoxSizeMode.CenterImage;
pBNew.Image = newImage;
}
if ((string)cBFilters.SelectedItem == "FillHoles")
{
pictureTransform = Grayscale.CommonAlgorithms.BT709.Apply(pictureTransform);
Threshold threshold = new Threshold(127);
threshold.ApplyInPlace(pictureTransform);
AForge.Imaging.Filters.FillHoles filter = new AForge.Imaging.Filters.FillHoles();
filter.MaxHoleHeight = 5;
filter.MaxHoleWidth = 15;
filter.CoupledSizeFiltering = false;
Bitmap newImage = filter.Apply(pictureTransform);
pbChoose.SizeMode = PictureBoxSizeMode.CenterImage;
pBNew.Image = newImage;
}
if ((string)cBFilters.SelectedItem == "Opening")
{
AForge.Imaging.Filters.Opening filter = new AForge.Imaging.Filters.Opening();
Bitmap newImage = filter.Apply(pictureTransform);
pbChoose.SizeMode = PictureBoxSizeMode.CenterImage;
pBNew.Image = newImage;
}
if ((string)cBFilters.SelectedItem == "Closing")
{
AForge.Imaging.Filters.Closing filter = new AForge.Imaging.Filters.Closing();
Bitmap newImage = filter.Apply(pictureTransform);
pbChoose.SizeMode = PictureBoxSizeMode.CenterImage;
pBNew.Image = newImage;
}
if ((string)cBFilters.SelectedItem == "Erosion")
{
AForge.Imaging.Filters.Erosion filter = new AForge.Imaging.Filters.Erosion();
Bitmap newImage = filter.Apply(pictureTransform);
pbChoose.SizeMode = PictureBoxSizeMode.CenterImage;
pBNew.Image = newImage;
}
if ((string)cBFilters.SelectedItem == "Dilatation")
{
AForge.Imaging.Filters.Dilatation filter = new AForge.Imaging.Filters.Dilatation();
Bitmap newImage = filter.Apply(pictureTransform);
pbChoose.SizeMode = PictureBoxSizeMode.CenterImage;
pBNew.Image = newImage;
}
if ((string)cBFilters.SelectedItem == "Edges")
{
AForge.Imaging.Filters.Edges filter = new AForge.Imaging.Filters.Edges();
Bitmap newImage = filter.Apply(pictureTransform);
pbChoose.SizeMode = PictureBoxSizeMode.CenterImage;
pBNew.Image = newImage;
}
}
public VideoProcessor()
{
background = null;
pixelateFilter = new Pixellate();
pixelateFilter.PixelSize = 10;
differenceFilter = new Difference();
thresholdFilter = new Threshold(15);
grayscaleFilter = new Grayscale(0.2125, 0.7154, 0.0721);
erosionFilter = new Erosion();
moveTowardsFilter = new MoveTowards();
filters1 = new FiltersSequence();
filters1.Add(pixelateFilter);
filters1.Add(grayscaleFilter);
filters2 = new FiltersSequence();
filters2.Add(differenceFilter);
filters2.Add(thresholdFilter);
filters2.Add(erosionFilter);
rat1 = new Tracker(640 / 2, 480 / 2, Color.Red);
rat2 = new Tracker(400, 300, Color.Green);
counter = 0;
}
public Closing(short[,] se)
{
this.errosion = new Erosion();
this.dilatation = new Dilatation();
this.errosion = new Erosion(se);
this.dilatation = new Dilatation(se);
}
public Bitmap process(Bitmap bmp)
{
Bitmap newImage = (Bitmap)bmp.Clone();
newImage = new AForge.Imaging.Filters.GrayscaleY().Apply(newImage);
newImage = new AForge.Imaging.Filters.Threshold(50).Apply(newImage);
newImage = new AForge.Imaging.Filters.Median().Apply(newImage);
newImage = new AForge.Imaging.Filters.Median().Apply(newImage);
newImage = new AForge.Imaging.Filters.Dilatation().Apply(newImage);
newImage = new AForge.Imaging.Filters.Median().Apply(newImage);
newImage = new AForge.Imaging.Filters.Erosion().Apply(newImage);
newImage = new AForge.Imaging.Filters.Erosion().Apply(newImage);
return(newImage);
}
public double GetTemperature()
{
var temp = 0.0;
var image = Image.FromFile(filename);
var grayscale = new Grayscale(0.2125, 0.7154, 0.0721);
image = grayscale.Apply(image);
var invert = new Invert();
image = invert.Apply(image);
var stats = new ImageStatistics(image);
var levelsLinear = new LevelsLinear
{
InGray = stats.Gray.GetRange(2.90)
};
image = levelsLinear.Apply(image);
var contrast = new ContrastStretch();
image = contrast.Apply(image);
var erosion = new Erosion();
image = erosion.Apply(image);
var blur = new GaussianBlur(2, 3);
image = blur.Apply(image);
var threshold = new Threshold(79);
image = threshold.Apply(image);
image.Save(processedFileName, System.Drawing.Imaging.ImageFormat.Jpeg);
image.Dispose();
var text = Recognise();
double.TryParse(text.Replace(',', '.'), out temp);
return temp;
}
public void video_NewFrame(object sender, NewFrameEventArgs eventArgs)
{
// get new frame
CheckForIllegalCrossThreadCalls = false;
Bitmap bitmap = (Bitmap)eventArgs.Frame.Clone();
if (pictureBox1.Image == null)
{
bitmap.Save(@"modelo0.jpg");
bgFrame = bitmap;
}
else
{
try
{
bgFrame = (Bitmap)pictureBox1.Image.Clone();
//bitmap.Save(@"currImage.jpg");
currentFrame = (Bitmap)bitmap.Clone();
Bitmap gcurrent = Grayscale.CommonAlgorithms.BT709.Apply(bitmap);
Bitmap gbground = Grayscale.CommonAlgorithms.BT709.Apply(bgFrame);
Difference differenceFilter = new Difference();
differenceFilter.OverlayImage = gbground;
Bitmap currentImg = differenceFilter.Apply(gcurrent);
//bloqueo temporal de current image
BitmapData currentData = currentImg.LockBits(new Rectangle(0, 0, framesProcessing.fWidth,
framesProcessing.fHeight), ImageLockMode.ReadWrite, PixelFormat.Format8bppIndexed);
//**Thresholdfilter
Threshold thresholdFilter = new Threshold(15);
thresholdFilter.ApplyInPlace(currentData);
IFilter erosionFilter = new Erosion();
Bitmap tmp2 = erosionFilter.Apply(currentData);
currentImg.UnlockBits(currentData);
i = framesProcessing.CalculateWhitePixels(tmp2);
if (i > 300)
{
mov = mov2 = true;
}
else
mov = false;
pictureBox2.Image = currentImg;
}
catch{//MessageBox.Show(ex.Message.ToString());
}
}
pictureBox1.Image = bitmap;
}
public static Bitmap Erosion(Bitmap bmp)
{
// create filter
Erosion filter = new Erosion();
// apply the filter
filter.Apply(bmp);
return bmp;
}
private void cBFilters_SelectedIndexChanged(object sender, EventArgs e)
{
Bitmap pictureTransform = (Bitmap)pbChoose.Image;
if ((string)cBFilters.SelectedItem == "HSL_Filter")
{
AForge.Imaging.Filters.SaturationCorrection filter = new SaturationCorrection(0.1);
Bitmap newImage = filter.Apply(pictureTransform);
pbChoose.SizeMode = PictureBoxSizeMode.CenterImage;
pBNew.Image = newImage;
}
if ((string)cBFilters.SelectedItem == "Mediana")
{
AForge.Imaging.Filters.Median filter = new Median();
Bitmap newImage = filter.Apply(pictureTransform);
pbChoose.SizeMode = PictureBoxSizeMode.CenterImage;
pBNew.Image = newImage;
}
/*if ((string)cBFilters.SelectedItem == "Fourier_Transformation")
* {
* Complex[] dst = new Complex[n];
*
* AForge.Math.FourierTransform filter = AForge.Math.FourierTransform.DFT();// .FromBitmap(pictureTransform);
* Bitmap newImage = filter.Apply();
* pbChoose.SizeMode = PictureBoxSizeMode.CenterImage;
* pBNew.Image = newImage;
* }*/
if ((string)cBFilters.SelectedItem == "Binarization")
{
pictureTransform = Grayscale.CommonAlgorithms.BT709.Apply(pictureTransform);
Threshold threshold = new Threshold(127);
threshold.ApplyInPlace(pictureTransform);
pbChoose.SizeMode = PictureBoxSizeMode.CenterImage;
pBNew.Image = pictureTransform;
}
if ((string)cBFilters.SelectedItem == "Grayscale")
{
AForge.Imaging.Filters.Grayscale filter = new AForge.Imaging.Filters.Grayscale(0.2125, 0.7154, 0.0721);
Bitmap newImage = filter.Apply(pictureTransform);
pbChoose.SizeMode = PictureBoxSizeMode.CenterImage;
pBNew.Image = newImage;
}
if ((string)cBFilters.SelectedItem == "FillHoles")
{
pictureTransform = Grayscale.CommonAlgorithms.BT709.Apply(pictureTransform);
Threshold threshold = new Threshold(127);
threshold.ApplyInPlace(pictureTransform);
AForge.Imaging.Filters.FillHoles filter = new AForge.Imaging.Filters.FillHoles();
filter.MaxHoleHeight = 5;
filter.MaxHoleWidth = 15;
filter.CoupledSizeFiltering = false;
Bitmap newImage = filter.Apply(pictureTransform);
pbChoose.SizeMode = PictureBoxSizeMode.CenterImage;
pBNew.Image = newImage;
}
if ((string)cBFilters.SelectedItem == "Opening")
{
AForge.Imaging.Filters.Opening filter = new AForge.Imaging.Filters.Opening();
Bitmap newImage = filter.Apply(pictureTransform);
pbChoose.SizeMode = PictureBoxSizeMode.CenterImage;
pBNew.Image = newImage;
}
if ((string)cBFilters.SelectedItem == "Closing")
{
AForge.Imaging.Filters.Closing filter = new AForge.Imaging.Filters.Closing();
Bitmap newImage = filter.Apply(pictureTransform);
pbChoose.SizeMode = PictureBoxSizeMode.CenterImage;
pBNew.Image = newImage;
}
if ((string)cBFilters.SelectedItem == "Erosion")
{
AForge.Imaging.Filters.Erosion filter = new AForge.Imaging.Filters.Erosion();
Bitmap newImage = filter.Apply(pictureTransform);
pbChoose.SizeMode = PictureBoxSizeMode.CenterImage;
pBNew.Image = newImage;
}
if ((string)cBFilters.SelectedItem == "Dilatation")
{
AForge.Imaging.Filters.Dilatation filter = new AForge.Imaging.Filters.Dilatation();
Bitmap newImage = filter.Apply(pictureTransform);
pbChoose.SizeMode = PictureBoxSizeMode.CenterImage;
pBNew.Image = newImage;
}
if ((string)cBFilters.SelectedItem == "Edges")
{
AForge.Imaging.Filters.Edges filter = new AForge.Imaging.Filters.Edges();
Bitmap newImage = filter.Apply(pictureTransform);
pbChoose.SizeMode = PictureBoxSizeMode.CenterImage;
pBNew.Image = newImage;
}
}
// 선 굵게, 24비트로 넣어줘야함
public static Bitmap thick(Bitmap source)
{
///////////// ini 객체 생성 시작 /////////////////////////////////////////////////////
//현재 프로그램이 실행되고 있는정보 가져오기: 디버깅 모드라면 bin/debug/프로그램명.exe
FileInfo exefileinfo = new FileInfo(@"C:\Program Files\PLOCR\PLOCR.exe");
string pathini = exefileinfo.Directory.FullName.ToString(); //프로그램 실행되고 있는데 path 가져오기
string fileName = @"\PLOCRconfig.ini"; // 환경설정 파일명
string filePath = pathini + fileName; //ini 파일 경로
PLOCR.IniUtil ini = new PLOCR.IniUtil(filePath); // 만들어 놓았던 iniUtil 객체 생성(생성자 인자로 파일경로 정보 넘겨줌)
//////////// ini 객체 생성 끝 /////////////////////////////////////////////////////////
int order = int.Parse(ini.GetIniValue("선굵기값", "굵게횟수"));
for (int i = 0; i < order; i++)
{
Bitmap tmp = (Bitmap)source; // 중요! 한번 이미지 처리가 끝난 비트맵 source 는 clone 함수로 보내기 전에 다시 한번 (Bitmap) 처리 해줘야함, 이유는 잘 모르겠음
// convert to 24 bits per pixel
source = ImageProcess.Clone(tmp, PixelFormat.Format24bppRgb);
// delete old image
tmp.Dispose();
Erosion filter = new Erosion();
filter.ApplyInPlace(source); ;
}
return source;
}
/// <summary>
/// processes Frame for Motion Detection based on frame comparison
/// </summary>
/// <param name="frame">
/// Takes in 2 Bitmap parameters, currentFrame and backgroundFrame
/// </param>
/// <returns>
/// frame in which motion is marked
/// </returns>
public Bitmap processFrame(params Bitmap[] frame)
{
Bitmap currentFrame = frame[0];
// create grayscale filter (BT709)
Grayscale filter = new Grayscale(0.2125, 0.7154, 0.0721);
Bitmap GScurrentFrame = filter.Apply(currentFrame);
if (this.backgroundFrame == null)
{
this.backgroundFrame = (Bitmap)GScurrentFrame.Clone();
GScurrentFrame.Dispose();
return currentFrame;
}
else
{
Difference differenceFilter = new Difference();
IFilter thresholdFilter = new Threshold(15);
// set backgroud frame as an overlay for difference filter
differenceFilter.OverlayImage = backgroundFrame;
Bitmap tmp = thresholdFilter.Apply(differenceFilter.Apply(GScurrentFrame));
//reduce noise
IFilter erosionFilter = new Erosion();
Bitmap tmp1 = erosionFilter.Apply(tmp);
tmp.Dispose();
// Highlight Motions
IFilter extractChannel = new ExtractChannel(RGB.G);
Bitmap redChannel = extractChannel.Apply(currentFrame);
Merge mergeFilter = new Merge();
mergeFilter.OverlayImage = tmp1;
Bitmap t3 = mergeFilter.Apply(redChannel);
ReplaceChannel rc = new ReplaceChannel(RGB.G, t3);
t3 = rc.Apply(currentFrame);
this.backgroundFrame = (Bitmap)GScurrentFrame.Clone();
redChannel.Dispose();
tmp1.Dispose();
GScurrentFrame.Dispose();
return t3;
}
}
public Closing()
{
this.errosion = new Erosion();
this.dilatation = new Dilatation();
}
/// <summary>
/// Initializes a new instance of the <see cref="Opening"/> class.
/// </summary>
///
/// <param name="se">Structuring element.</param>
///
/// <remarks><para>See documentation to <see cref="Erosion"/> and <see cref="Dilatation"/>
/// classes for information about structuring element constraints.</para></remarks>
///
public Opening(short[,] se)
{
errosion = new Erosion(se);
dilatation = new Dilatation(se);
}
// 선 굵게
private void button34_Click(object sender, EventArgs e)
{
///////////// ini 객체 생성 시작 /////////////////////////////////////////////////////
//현재 프로그램이 실행되고 있는정보 가져오기: 디버깅 모드라면 bin/debug/프로그램명.exe
FileInfo exefileinfo = new FileInfo(@"C:\Program Files\PLOCR\PLOCR.exe");
string pathini = exefileinfo.Directory.FullName.ToString(); //프로그램 실행되고 있는데 path 가져오기
string fileName = @"\PLOCRconfig.ini"; // 환경설정 파일명
string filePath = pathini + fileName; //ini 파일 경로
DocumentAnalysis.IniUtil ini = new DocumentAnalysis.IniUtil(filePath); // 만들어 놓았던 iniUtil 객체 생성(생성자 인자로 파일경로 정보 넘겨줌)
//////////// ini 객체 생성 끝 /////////////////////////////////////////////////////////
Bitmap source = Global.source;
Bitmap tmp = source;
// convert to 24 bits per pixel
source = imageProcess.Clone(tmp, PixelFormat.Format24bppRgb);
// delete old image
tmp.Dispose();
Erosion filter = new Erosion();
filter.ApplyInPlace(source);
Global.source = source;
pictureBox1.Image = Global.source;
pictureBox1.Refresh();
textBox24.Text = (int.Parse(textBox24.Text) + 1).ToString();
ini.SetIniValue("선굵기값", "굵게횟수", textBox24.Text.ToString());
//string path = calculator.CreateFileCheck("C:\\Program Files\\PLOCR\\prescription.png");
//pictureBox1.Image.Save(path);
}
private Bitmap XXX(Bitmap bmpBefore, Bitmap bmpAfter)
{
var filter = new Grayscale(0.2125, 0.7154, 0.0721);
bmpBefore = filter.Apply(bmpBefore);
bmpAfter = filter.Apply(bmpAfter);
// create filters
var differenceFilter = new Difference();
IFilter thresholdFilter = new Threshold(15);
// set backgroud frame as an overlay for difference filter
differenceFilter.OverlayImage = bmpBefore;
// apply the filters
Bitmap tmp1 = differenceFilter.Apply(bmpAfter);
Bitmap tmp2 = thresholdFilter.Apply(tmp1);
IFilter erosionFilter = new Erosion();
// apply the filter
Bitmap tmp3 = erosionFilter.Apply(tmp2);
IFilter pixellateFilter = new Pixellate();
// apply the filter
Bitmap tmp4 = pixellateFilter.Apply(tmp3);
return tmp4;
}
/// <summary>
/// Initializes a new instance of the <see cref="Opening"/> class.
/// </summary>
///
/// <param name="se">Structuring element.</param>
///
/// <remarks><para>See documentation to <see cref="Erosion"/> and <see cref="Dilatation"/>
/// classes for information about structuring element constraints.</para></remarks>
///
public Opening( short[,] se )
{
errosion = new Erosion( se );
dilatation = new Dilatation( se );
}
public static Bitmap ApplyErosion(Bitmap pBitmap)
{
Erosion filter = new Erosion();
return filter.Apply(pBitmap);
}
private void DetectMotion()
{
if ((_previousFrame != null) && (_currentFrame != null))
{
Grayscale grayscaleFilter = new Grayscale(0.2125, 0.7154, 0.0721);
using (Bitmap frame1GS = grayscaleFilter.Apply(_previousFrame))
{
using (Bitmap frame2GS = grayscaleFilter.Apply(_currentFrame))
{
Difference differenceFilter = new Difference();
IFilter thresholdFilter = new Threshold(15);
// set backgroud frame as an overlay for difference filter
differenceFilter.OverlayImage = (Bitmap)frame1GS;
// apply the filters
using (Bitmap tmp1 = differenceFilter.Apply((Bitmap)frame2GS))
{
using (Bitmap tmp2 = thresholdFilter.Apply(tmp1))
{
IFilter erosionFilter = new Erosion();
// apply the filter
using (Bitmap tmp3 = erosionFilter.Apply(tmp2))
{
int whitePixelsCount = CalculateWhitePixels(tmp3);
if (whitePixelsCount > 1000)
{
MotionDetectionEvent motionEvent = new MotionDetectionEvent()
{
CameraDevice = _camera,
NumberOfPixelsDetected = whitePixelsCount,
InputDevice = _camera
};
MotionDetectedEventArgs args = new MotionDetectedEventArgs(motionEvent);
OnMotionDetected(args);
}
//// extract red channel from the original image
//IFilter extrachChannel = new ExtractChannel(RGB.R);
//Bitmap redChannel = extrachChannel.Apply(frame2);
//// merge red channel with motion regions
//Merge mergeFilter = new Merge();
//mergeFilter.OverlayImage = tmp3;
//Bitmap tmp4 = mergeFilter.Apply(redChannel);
//// replace red channel in the original image
//ReplaceChannel replaceChannel = new ReplaceChannel(RGB.R, tmp4);
//replaceChannel.ChannelImage = tmp4;
//Bitmap tmp5 = replaceChannel.Apply(frame2);
}
}
}
}
}
}
}