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This is a really good job for a profiler, the difference may be something subtle like the way the C# compiler generates MSIL versus the VB one. Yes, even a line-for-line translation of exactly the same code as you've done above will have different MSIL (in contrast to what your other answer has given).
There are some performance improvements you can implement above. You convert the pixel data from an integer, to a color, back to an integer, then back to a color, then back to an integer
Pixel Data->ToARGB->BT_601->Convert.ToInt32->FromARGB->ToArgb
In my mind it would be simpler to use bit level math for this. Make the BT_601 take the integer data, like:
private static int BT_601(int c)
{
int gs = (((0x00FF0000 & c) >> 16) * 0.299) << 16) +
(((0x0000FF00 & c) >> 8 ) * 0.587) << 8) +
(((0x000000FF & c) * 0.114);
return (0xFF000000 & c) | (gs << 16) | (gs << 8) | gs;
}
Which is much faster compiler wise than trying to use all those conversions and function calls.
You may also want to do LockBits twice, once with read permission (not read/write) and the next time with write permission (not read). The one-way access helps optimize access to the buffer. You can also get about a 2 time increase by using pointers and unsafe code. You can also try to wrap your for loop in an unchecked block, which will keep the framework from doing bounds checks each time you access the array.
modified 10-Jun-13 1:14am.
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Ron,
Thank you for the well deserved kick in the pants on optimizing the individual grayscale calculations. 
I was too pleased with myself for figuring out that I could read/write the color as an integer versus the separate alpha, red, green, blue bytes and performance boost that yielded as those individual bytes are then re-assembled to recreate that integer value in the Color structure.
As I am writing this, I have realized that my logic (and attempt to optimize) was completely flawed from the start as it was all premised on creating and using a Color structure. There is absolutely no need for this structure other than as a pretty box. Oh-well, back to the drawing board. 
I have never used a profiler, but I will look into it. Unless someone else has an explanation, I will have to chalk this up to the VB compiler optimizing this code segment better than the C# compiler.
Thanks again, you made me re-think this and also made me realize that I have become susceptible to falling for the shiny box.
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Hi
I am creating a complaint system, I am able to get the complaint details, and have employees leave comments, but I am unable to display the comments left on a case, as more than one person may pick up the case and leave their own comments, so I need a good way to display the comments left, the database will only have 4 columns, 1st with case ID, 2nd with employee name 3rd with date and 4th is the message columns, So i need to display 2nd, 3rd and 4th columns, I have looked at using the datagridview, but as the message columns is a memo field, it is not display as i want it to.
I would like the comments to be displayed as follows
Employees name
Date
Message
e.g
testuser1
09/06/2013
Test message about a sale made on the 31/05/13
-------------------------------------------------------------
testuser2
10/09/13
customer have been send a replacement item on 01/06/13
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You could think of using a rich text box for your memo field.
You can also try and load just a porting of this text in a grid view column for the memo.
One a user clicks on the column display a popup with complete memo data.
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Hello.
Some buddy help me for .How to search the data from database.(sqlserver) .in Asp.net
Thanks
Please help me
Raj kaushal
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Wrong forum, try ASP.NET, Database or Javscript.
Use the best guess
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If you need JavaScript help, there is a JavaScript forum as well.
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The first hit I found in Google was this[^].
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Hi,
I am used to programming in MFC42. This environment has various wizards. I used (an abused) them, but was at any stage aware of what they were supposed to do. C#.Net exposes me to some 'God'idea It seems to determine what I'm allowed to write, and what not! How do I defeat this.
Regards,
Bram van Kampen
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It would be nice if you descibed what you meant by "God idea". It's pretty much impossible to tell you what's going on without that.
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I'm sorry Bram, but you will have to be a lot more specific than that. It may be apparent to you what is currently frustrating you, but I have no idea what area you are working on so I can't even begin to imagine what is causing this angst for you.
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Bram van Kampen wrote: How do I defeat this.
You don't: whatever this might be. You learn the system and work within the rules. And, from a personal point of view, my experience of learning C# is that it also has wizards which are extremely useful, and allows you to do what you want when you want; I have not come across anything like you describe.
Use the best guess
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Hi Richard,
Richard MacCutchan wrote: You don't: whatever this might be. You learn the system and work within
the rules. And, from a personal point of view, my experience of learning C# is
that it also has wizards which are extremely useful, and allows you to do what
you want when you want; I have not come across anything like you describe.
Well, I've cooled down now! Sorry for the outburst. What you say makes eminent sense. It was one of those occasions that I was ready to throw the laptop tru the plate glass window beside me. It does not happen often, but, there you go. I take it that you never had that emotion.
I am trying to establish a core SQL DB, with certain core fixed data. (Table with User Name, Password, Authority, Privileges)Authority relates to a different DB table where roles are described.
In mfc42 I know what the wizzards do, can replicate it by hand if needed.
In C#.NET,I find it difficult to determine what the code generators do, an why.
Aspects take on a'God' like nature, when the compiler takes's own course,rather than the course I thought I steered it in.
Reading more,learning more...
Bram.
Bram van Kampen
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Bram van Kampen wrote: I take it that you never had that emotion.
You take it wrong; ask anyone who ever worked with me.
Bram van Kampen wrote: Aspects take on a'God' like nature, when the compiler takes's own course,rather than the course I thought I steered it in.
I disagree. The wizards are there to help, but you do need to understand what they are trying to help you with. I have not used MFC for a long time but I do recall being totally lost the first time I used it, but only because I had not spent time reading the documentation first.
I'm far from being experienced with databases in .NET, but there are a number of different options, so you do need to understand in advance which option it is trying to build for you.
Given that you are obviously thinking about the problem, you are bound to succeed. And there are plenty of very clever people here who will help you with your (calm and reasonable) questions.
Use the best guess
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Possibly toggle Intellisense ... Edit/Toggle Completion Mode. I'm guessing ...
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hi, I want to make a online class but I don't know how can I do that.
please help me.
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Your first step is to actually forget about the code you think you need. Start off by working out what it is you actually need for this online class. Gather your requirements. For instance, off the top of my head:
Do you have to register for a class?
Does it need to be interactive?
Does it need to allow a question section?
Is it interactive?
Do you need to record the sessions?
Do you have to pay for courses?
How many people will be able to view a class at one time?
These are only a few of the things you need to answer before you think of writing a single line.
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ok, I want to make a online class with 6 or 8 students per class and they should pay for class.
but that's not my problem.
I can't make a voice chat for class. I need a code for voice chat for 6-8 people.
please help me, now.
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And what's the platform? Is it web based?
Seriously, you need to break the problem down a lot more before you try and write code. You still have a lot of questions to answer first.
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Yes, it is web base.
I know that is hard and a big project.
now I need to know how can I send and resive voice and video in web. like a chat room.
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This[^] might be a good starting point for you.
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I didn't understand that.
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What didn't you understand?
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no, that link can't help me. becuase that will be lock soon. I need to make it myself and upload it in a Iranin host. if I used a site or app like that that will be locked soon.
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