Re: Need a help for image processing - C# Discussion Boards

Need a help for image processing

30-Aug-05 23:05

Hello

The best way to do it is to use DirectShow. You can try to interop it or to use managed extension of DirectShow 9.

There are couple of article on CP about DirectShow usage in C# applications, for example here is one [^].

You can look at my "Motion Detection" article for a sample of communication with local capture device such as USB webcam.

With best regards,
Andrew

Re: Multimedia

Lars Niedziolka31-Aug-05 14:38

Lars Niedziolka

31-Aug-05 14:38

I belief, that most Webcams support TWAIN and/or WIA as interface. Here in CodeProject you finds Wrappers for TWAIN and WIA.

TWAIN is a normed API to read still images like scanner and webcams.
WIA is the newer API (and supported since Windows 2K).

See: .NET TWAIN image scanner
See: WIA Scripting and .NET

Lars Niedziolka

msmkumar30-Aug-05 20:30

30-Aug-05 20:30

Hai
Im selvamuthukumar i need a help about image processing using c#.Net Win Application.Actulay i have a image that is face of a man.I want to divide a face in to various zones. Input: Skin segmentation image, 3 coordinates that provide the location of the center of the eyes and mouth. Output: The face should be divide in to various zones for Example draw a curve in one eye is one zone . Pixels within each zone must be uniquely identified.

Thanks & Regard's
m.selvamuthukumar

Andrew Kirillov30-Aug-05 23:17

30-Aug-05 23:17

Hello

I think that my article "Image Processing Lab in C#" can be a good start for you. Also there is series of article from Christian Graus about image processing.

So, first of all you can try some color filtering techniques to locate face skin regions. It can be done using RGB or HSL color space. There are filters in my lab for it. Or you can try other color spaces to achieve this task.

For eyes localization you can try also some combinations of color filtering. After binarization you can use blob counter/extractor to locate each object (eyes in your case). The idea of blob extractor can be inspired by Connected Component Labeling.

With best regards,
Andrew

People are strange

Andrew Kirillov31-Aug-05 2:45

31-Aug-05 2:45

Strange people are here sometimes. Just put the "1" mark without any comments and that's all.

I've made so bad comment? There is something wrong? So, why not just to reply me with your ideas? I thought that it is the place for sharing ideas. And if one's idea is not the same as yours, than it is not a reason just to put "1".

May be I am wrong? So, correct me, please.

With best regards,
Andrew

Re: People are strange

msmkumar31-Aug-05 3:03

31-Aug-05 3:03

Hai
im ver sorry for that.
Thanks
m.smskumar

msmkumar31-Aug-05 3:00

31-Aug-05 3:00

Hai
Thanks for ur quick reply. but i can't get clear idea. i also download ur image processing lab in c# demo. But i can't run that application i got error. how can i run that demo application .it has one exe and six Dlls.

Thanks & Regard's
m.selvamuthukumar

Andrew Kirillov31-Aug-05 3:07

31-Aug-05 3:07

Hello

What sort of error did you get ? Maybe you are missing .NET Framework ?

Andrew

msmkumar31-Aug-05 3:32

31-Aug-05 3:32

Hai
i run ilab exe i got the error System.IO.FileNotFoundException in the Just in time debugging window how can i solve this plz reply me.

Thanks
m.kumar

Andrew Kirillov31-Aug-05 3:37

31-Aug-05 3:37

Are all DLLs in the same directory as the main executable module? If they are, then the application should work. If they are not, then you will get the described exception.

Andrew

Andrew Kirillov31-Aug-05 3:29

31-Aug-05 3:29

About idea.

You can define a color range for face skin. For example, you can define a range around yellow color and use it for filtering. So, only pixels, which color falls into the specified range, are preserved and other pixels are filled with background color.

There are many works utilizing the idea. And different color spaces were researched for applying to the task.

You can look at the survey for more information:
"Detecting Faces in Images: A Survey - M. Yang, N. Ahuja, D. Kriegman"

With best regards,
Andrew

msmkumar31-Aug-05 21:19

31-Aug-05 21:19

Hello
Thanks for ur reply. Now i got a center coordinate[center coordinate of a image is image.width/2 and image.hight/2 is it correct] of a imge.using this cooridinate to i filter the color of a image and get a edge of a image. i need a sample coding for filtering the image using that center coodinate.
can i send a mail to you? Because i think mail is better way for explain my problem also i can send the sample images. I expect your reply.

Thanks & Regards,
M.selvamuthukumar

Andrew Kirillov31-Aug-05 22:14

31-Aug-05 22:14

Hello

Yes, you can send me an email.

Andrew

msmkumar1-Sep-05 20:17

1-Sep-05 20:17

Hello
Thanks for ur reply. I send a mail to you. I expert your reply.
Thanks
M.selvamuthukumar

msmkumar4-Sep-05 17:54

4-Sep-05 17:54

Hello
Did you get my mail and that attached document? Please give me a good idea and smple code for me. i expert your reply.

Thanks & Regards
m.kumar

msmkumar8-Sep-05 21:38

8-Sep-05 21:38

Hello
I hvae a series of points using that ponit to draw a lines using drawlines method it will draw a line but the pen start from the corner of the bitmapimage. after draw the line it will go to the corner. i want only draw a line only in the series of lines .how i do.my coding is

Point[] pt1 = new Point[m_Bitmap.Height];

Graphics g = Graphics.FromImage(m_Bitmap);
Pen pen = new Pen(Color.Blue,2);

for(int y=0;y< m_Bitmap.Height;++y)
{
for(int x=0; x < m_Bitmap.Width; ++x )
{
if( m_Bitmap.GetPixel(x,y).R != 0 & m_Bitmap.GetPixel(x,y).G != 0 & m_Bitmap.GetPixel(x,y).B != 0 )
{

pt1[y] = new Point(x,y);
break;
}

}

}

g.DrawLines(pen,pt1);

Thanks & Regard's
M.selvamuthukumar

msmkumar9-Sep-05 18:22