Custom border color for Textbox is not working when using WS_EX_COMPOSITED style to the windows forms - C# Discussion Boards

Sorry, I didn't quite understand how colormatrix works. Thought it might help since it seems to convert images to greyscale faster than manually iterating through pixels.

Using some of your articles and they've helped a lot thanks.

It does convert to grayscale but that is not going to tell you what an image contains. I assume you are trying to get to the point where you either have back or white pixels (two-tone).

This method is naturally a first instinct for image processing as you can hope to get a 'shape' from this data. But it's not so simple, where do you draw the line for the contrast? you cant use a fixes value because the image will change depending on the lighting.

How is it you intend to detect the shapes of the hands in the image? (assuming you are still attempting the sign language application)

Life goes very fast. Tomorrow, today is already yesterday.

Yes, you are probably right, a binary image will most likely be my next step. One idea that comes to mind for this is to normalize the image tones and then using a range corresponding to skin tone to extract the hand.

Although I doubt this will be the best method as I'm sure there are better ones out there.

With regards to shapes, "cascade classifiers" is something I am going to have a look at and see if it works. I know it works for face recognition, but will have to see if I can get results on the sign language.

Well you sure have a big challenge on your hands...

I take it you have seen the bitmap functions for GetPixel() and SetPixel()? This is slow and as you have mentioned using unsafe code - this should be faster. I don't think I have seen any example of another method to obtain/assign pixel data from an image.

One thing that does come to mind (Not tested so can't say it will be good idea) is to just create a 2D array of pixel data from the image and use that data. I don't see you will ever need to set the pixel data back to the image at any point so maybe this is something worth looking into (performance wise)

All the best with your task anyway Wink | ;)

Life goes very fast. Tomorrow, today is already yesterday.

Thanks

I did actually think of that, so it's good to know I'm not the only one that thinks it might work Smile | :)

At the moment I'm getting 30FPS using the unsafe code, so hopefully won't have to resort to that, but will let you know if I end up trying it.

tvbarnard wrote:
At the moment I'm getting 30FPS using the unsafe code

At the moment it seems you are only converting to grayscale which is relatively quick compared to the processing your going to need to throw at it to get your desired end results. Your FPS will soon start to drop Wink | ;)

Life goes very fast. Tomorrow, today is already yesterday.

lol true

I am trying to give the custom boder color for the text box in C#. I am using XP operating system and visual studio 2008. I have subclassed the Textbox and override the WndProc method to handle the WM_PAINT message to give the custom border color to the text box.

// Text box code
public class SampleTextBox : TextBox
    {
        public SampleTextBox()
        {
            BorderStyle = BorderStyle.FixedSingle;
        }

        protected override void WndProc(ref Message m)
        {
            switch (m.Msg)
            {
                case 0x000F: // WM_PAINT
                    base.WndProc(ref m);
                        
                    Control control = Control.FromHandle(Handle);
                    Graphics g = Graphics.FromHwnd(Handle);

                    ControlPaint.DrawBorder(g, control.ClientRectangle, Color.YellowGreen, ButtonBorderStyle.Solid);
                  
                    g.Dispose();
                    break;                
                default:
                    base.WndProc(ref m);
                    break;
            }
        }
    }

// Form code

public class SampleForm : Form
    {
        public SampleForm()
        {
            BackColor = Color.SteelBlue;
        }

        protected override CreateParams CreateParams
        {
            get
            {
                CreateParams cp = base.CreateParams;
                cp.ExStyle |= 0x02000000; /*WS_EX_COMPOSITED*/
                return cp;
            }
        }
    }


public class Form2 : SampleForm
    {
        private SampleTextBox textbox1;

        public Form2()
        {

            textbox1 = new SampleTextBox();
            textbox1.Location = new Point(50, 50);

            this.Controls.Add(textbox1);

        }
    }

I am using WS_EX_COMPOSITED extened window style to my form to avoid the filckering because i am doing custom painting in my form. If i use WS_EX_COMPOSITED style with form , the border color of Text box comes with default color, that is black color while opening the form . But if i click and move the mouse in the non client area like border or titlebar of the form, the border color changes to color (Color.YellowGreen) which i specified in the Paint message of Textbox.

If I comment the "cp.ExStyle |= 0x02000000; /*WS_EX_COMPOSITED*/ " line, then the border always comes with the color what i specified in the Paint message of Textbox.

Can anyone please tell why this is happening and how can I achieve the custom border for the text box when WS_EX_COMPOSITED style applied to its parent control(form)?

Thanks in advance.

Mutpan.

Instead of WS_EX_COMPOSITED you can try like this to reduce flickering:

public class Form2 : SampleForm
    {
        private SampleTextBox textbox1;

        public Form2()
        {
            this.SetStyle(ControlStyles.AllPaintingInWmPaint |
                ControlStyles.ResizeRedraw | ControlStyles.OptimizedDoubleBuffer, true);
            this.UpdateStyles();

            textbox1 = new SampleTextBox();
            textbox1.Location = new Point(50, 50);

            this.Controls.Add(textbox1);

        }
    }

using the styles "this.SetStyle(ControlStyles.AllPaintingInWmPaint | ControlStyles.ResizeRedraw | ControlStyles.OptimizedDoubleBuffer, true);" is not reducing the flickering in the non client area like title bar. So i should use WS_EX_COMPOSITED style.

i have a problem when i use the httpwebrequest for a page the page is displayed correctly and when but ispostback is always false.
i m sending the viewstate data too but it is still false
how can i make it to true so that i can access the full data.
the code is as follow

static CookieContainer cookieJar = new CookieContainer();

public string PostContenct(string dataPost, string srcuri)
       {
           Uri uri = new Uri(srcuri);
           string data = dataPost;
           //if (uri.Scheme == Uri.UriSchemeHttp)
           //{


            HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(uri);
               request.CookieContainer = cookieJar;
               request.AllowAutoRedirect = true;
               request.Method = WebRequestMethods.Http.Post;
               request.ContentLength = data.Length;
               //request.AllowAutoRedirect = true;
               request.ContentType = "application/x-www-form-urlencoded";

               StreamWriter writer = new StreamWriter(request.GetRequestStream());
               writer.Write(data);
               writer.Close();

               HttpWebResponse response = (HttpWebResponse)request.GetResponse();
               int cookiecount = cookieJar.Count;
               StreamReader reader = new StreamReader(response.GetResponseStream());
               string str = response.StatusDescription;
               string tmp = reader.ReadToEnd();
               response.Close();
               return tmp;
           //}
           //else
           //{
           //    return "";
           //}

       }

thanks

amirzada

Don't you think this question is more appropriate for ASP.Net forum.

Manas Bhardwaj
Please remember to rate helpful or unhelpful answers, it lets us and people reading the forums know if our answers are any good.

yea it is system.net class and can b used in both asp.net and c#

thanx alot i have made it.

thanx

amirzada

I have a variable

byte[] rxData;

And VS is complaining that it is unassigned. However i dont want to assign it as this is done in the switch statement that follows.

does anyone know why it still complains

;switch (rxMessage[3])
              {
                 case 0x46: // full Display Area
                    for (int i = 4; i &amp;amp;lt;= 1028; i++)
                    {rxData[i - 4] = rxMessage[i];}
                    break;
                 case 0x42: // This command shall switch off the LCD and clear the LCD RAM
                    rxData[0] = 0;
                    break;
                 case 0x4f: // LCD On Off
                    rxData[0] = rxMessage[4];
                    break;
                 case 0x43:
                    rxData[0] = rxMessage[4];
                    break;
                 default:
                    //error
                    throw new InvalidDataException("Error: Incorrect Subcommand type may have been found");
              }

Hi,

maybe you have to initialise rxData first. It is set to null by default, but to assign values to the array (using an index like 0 at nul won't work). It must be initialised like this:

byte[] rxData = new byte[1024];

Regards
Sebastian

It's not a bug, it's a feature!

Check out my CodeProject article Permission-by-aspect.

Me in Softwareland.

You have not defined the array.

byte[] rxData = new byte[someNumber];

Thanx For both of your answers this does allow the code to compile.

Was just hoping i could declaire it and give it a value in the switch without it complaining. The flow was being forced through the switch so though it would work.

Thanx for your time

gwithey wrote:
Was just hoping i could declaire it and give it a value in the switch without it complaining. The flow was being forced through the switch so though it would work.

No, it wouldn't work: that is the whole point.
To cut down your code a little:

byte[] rxData;
rxData[0] = rxMessage[4];

You would still get your compile error, since rxData is null, thus rxData[0] does not exist. This is why the compiler complains.

byte[] rxData = new byte[1024];
rxData[0] = rxMessage[4];

Is fine, since rxData is no longer null, and rxData[0] (through rxData[1023]) exists and can be assigned.

No trees were harmed in the sending of this message; however, a significant number of electrons were slightly inconvenienced.

This message is made of fully recyclable Zeros and Ones

Yeah that makes sense thanx it is clearer now

please any one can tell me how can i show a preview of the webcam video in a panel or picturebox using WIA or WIAVideo Li or in any other way.....

thanks....

Here is exactly what you want: [^].
The provided source code uses avicap32.dll, so if you want a WIA solution check this article: [^].

I hope these links help you, Smile | :)

Nuri

thanks for help...but in that way have to use a commen dialog box. isn't it? but i want to show my webcam preview in a panal or picturebox without using commen dialog box...is there a way to do that....?

A S E L A

S K Y wrote:
but i want to show my webcam preview in a panal or picturebox without using commen dialog box...

I don't understand that.

The source code from the second link uses exactly the PictureBox control to show the captured video (picture by picture using timer). Please check out the provided source code for the article. The are 2 versions of the code available (for C# and VB). You can use the provided technique and place the PictureBox wherever you want.

Best wishes! Smile | :)

Nuri

hi...i couldn't download the zip file bcz got server error. do you have that zip file with you...(first article)

A S E L A

I also have the server error for the first article. Frown | :(

But i have downloaded and tested the source from the second one. It uses exactly the WIA, the PictureBox control and it is working! Smile | :)