C# Discussion Boards - CodeProject

19-Mar-06 5:46

Hi , i am currently working on the steganography Project for My B.Tech Final Year Project .plz could any one help me out , i am facing problems in understanding the code that i have downloaded from codeproject .....plz guide me .!!! i have a very little time left .............. Confused | :confused:

AMAN ANWAR

Dave Kreskowiak19-Mar-06 7:12

Dave Kreskowiak

19-Mar-06 7:12

If you have questions about the code the author posted, post a question in that articles message board. Go to the bottom of the article to post it.

nwr_mn wrote:
i have a very little time left

Don't get me started! Hmmm | :|

RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome

Ed.Poore19-Mar-06 7:13

Ed.Poore

19-Mar-06 7:13

nwr_mn wrote:
i am facing problems in understanding the code that i have downloaded from codeproject

You shouldn't have too much trouble since they're accompanied by usually excellent articles and the code should be commented. If the article is brief then it's because the code is easy to understand.

nwr_mn wrote:
i have a very little time left

Might help a tiny bit if you give us a specific problem, the world of programming is very very very very very very large indeed.

Ed

nwr_mn19-Mar-06 8:08

19-Mar-06 8:08

sir, it is very nice of u to respond to my query , i am actually facing the problem of how to read the LSB of the bitmaps.the code is no doubt commented but i am an average programmer so i am facing problems in understanding it ...plz could u help me out .
I am also having problems in writing the entire message lenght in to the first pixel of the bitmap .....plz help help Confused | :confused:

AMAN ANWAR

Ed.Poore19-Mar-06 8:33

Ed.Poore

19-Mar-06 8:33

Provide the code snippet which you're having trouble with and then we will be able to help you.

Ed

SQLite DB Experience Anyone?

leppie19-Mar-06 18:21

leppie

19-Mar-06 18:21

nwr_mn wrote:
i have a very little time left

Welcome to the real world, your holiday is over now, dont they teach you responsibility at university? Sigh | :sigh:

xacc.ide-0.1.3.2

redfish3419-Mar-06 5:44

redfish34

19-Mar-06 5:44

It sounds like SQLite is a nice database for standalone applications. Is this true for C#/NET apps? There are several NET wrappers out there for the DLL. Can someone give me some advice about what works and what does not? What NET wrapper should i get? Are there any pitfalls regarding set up and use that i should be aware of when developing C# apps?

Re: SQLite DB Experience Anyone?

Michael P Butler19-Mar-06 6:39

Michael P Butler

19-Mar-06 6:39

I use this library[^] for my Sqlite work. Seems to do the job well enough.

Michael

CP Blog [^] Development Blog [^]

Help Required in Steganography Project In C#

nwr_mn19-Mar-06 5:43

19-Mar-06 5:43

AMAN ANWAR

Dave Kreskowiak19-Mar-06 7:06

Dave Kreskowiak

19-Mar-06 7:06

You might want to ask an actual question.

About the only thing we can say to you is Google[^].

RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome

nwr_mn19-Mar-06 8:15

19-Mar-06 8:15

using System;
using System.IO;
using System.Text;

namespace Steganography
{
public class BMPCoverFile : ICoverFile
{

private string fileName;

public BMPCoverFile(string fileName) {
this.fileName = fileName;
}

public IStegoFile CreateStegoFile(string stegoFileName, string message, string password) {

// Open the cover
FileStream inStream = new FileStream(fileName, FileMode.Open, FileAccess.Read);

// Check whether the cover is a bmp file
char b = (char) inStream.ReadByte();
char m = (char) inStream.ReadByte();
if (!(b=='B' && m=='M'))
throw new Exception("The file is not a bitmap!");

// Check whether the bitmap is 24bit
byte[] buffer = new byte[2];
inStream.Seek(28, 0);
inStream.Read(buffer,0,2);
Int16 nBit = BitConverter.ToInt16(buffer, 0);
if (nBit!=24)
throw new Exception("The file is not a 24bit bitmap!");

// Read the header from the cover
int offset = 54; // Header Size
byte[] header = new byte[offset];
inStream.Seek(0, 0);
inStream.Read(header, 0, offset);

// Write the header to the stego file
FileStream outStream = new FileStream(stegoFileName, FileMode.Create, FileAccess.Write);

outStream.Write(header, 0, offset);

// Create the unicode encoding
UnicodeEncoding unicode = new UnicodeEncoding();

// Add the length of the message inside the first 4 bytes
byte[] messageBytes = AddLengthAhead(unicode.GetBytes(message));

// Encrypt the message
messageBytes = CryptoHelper.Encrypt(messageBytes, password);

// Encode the cover using the LSB method
inStream.Seek(offset, 0);
LSBHelper.Encode(inStream, messageBytes, outStream);

inStream.Close();
outStream.Close();

// Return a new BMPStegoFile
return new BMPStegoFile(stegoFileName, password);

}

private byte[] AddLengthAhead(byte[] messageBytes) {
int len = messageBytes.Length;
byte[] bLen = BitConverter.GetBytes(len);
byte[] ret = new byte[len + bLen.Length];
for (int i=0; i < bLen.Length; i++)
ret[i] = bLen[i];
for (int i=0; i < messageBytes.Length; i++)
ret[i+bLen.Length] = messageBytes[i];
return ret;
}

}

}

}

what is done in this code ?? it has been commented as Adding message bytes to the start of the pixels of the Bitmap.

AMAN ANWAR

Re: WinForms painting issue

Dave Kreskowiak19-Mar-06 12:42

Dave Kreskowiak

19-Mar-06 12:42

Once again, your best source for information is the person who wrote the code!

RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome

chloh19-Mar-06 5:13

chloh

19-Mar-06 5:13

> I guess it might have to caputre any Paint event in teh
> application and ignore it when this window is moving or resizing
But how do you know when the moving or resizing has finished?

I guess you should optimize your heavy painting code in the main form. You can start by enabling DoubleBuffer ControlStyles. Then optimize the paint code by only painting the invalidated portion.

reflexon

vatzcar19-Mar-06 2:48

19-Mar-06 2:48

hi,
i'm having error "Member not found." from the following code(in time of invoking member)..

<br />
foreach (MemberInfo mi in type.GetMember("test_mdi_Init"))<br />
{<br />
  type.InvokeMember (mi.Name.ToString(), <br />
  BindingFlags.Default | BindingFlags.InvokeMethod,<br />
  null,<br />
  ibaseObject,<br />
  arguments);<br />
}<br />

what could be the problem? thanx for help Smile | :)

Guffa19-Mar-06 3:01

Guffa

19-Mar-06 3:01

The flags of the member doesn't fit the flags that you have specified.

---
b { font-weight: normal; }

vatzcar19-Mar-06 5:20

19-Mar-06 5:20

the member "test_mdi_Init" is a public method. also if use 'BindingFlags.Public' it throws an exception "Attemp to access a missing member". so what do you suggest?

[Marc]19-Mar-06 6:38

[Marc]

19-Mar-06 6:38

BindingFlags.Default is 0, so you can remove that. I think you need BindingFlags.InvokeMethod | BindingFlags.Public | BindingFlags.Instance.

"..Commit yourself to quality from day one..it's better to do nothing at all than to do something badly.."
-- Mark McCormick

|| Fold With Us! || Pensieve || VG.Net ||

vatzcar19-Mar-06 17:46

19-Mar-06 17:46

thank you for your reply. BindingFlags.InvokeMethod works fine. i didn't make my method 'ststic', that's why i was having exception. Sorry, my mistake Frown | :(

vatzcar19-Mar-06 17:47