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信息隐藏指在设计和确定模块时,使得一个模块内包含的特定信息(过程或数据),对于不需要这些信息的其他模块来说,是透明的。
传统的信息隐藏起源于古老的隐写术。如在古希腊战争中,为了安全地传送军事情报,奴隶主剃光奴隶 的头发,将情报文在奴隶的头皮上,待头发长起后再派出去传送消息。我国古代也早有以藏头诗、藏尾诗、漏格诗以及绘画等形式,将要表达的意思和“密语”隐藏在诗文或画卷中的特定位置,一般人只注意诗或画的表面意境,而不会去注意或破解隐藏其中的密语。 信息隐藏的发展历史可以一直追溯到"匿形术(Steganography)"的使用。"匿形术"一词来源于古希腊文中"隐藏的"和"图形"两个词语的组合。虽然"匿形术"与"密码术(Cryptography)"都是致力于信息的保密技术,但是,两者的设计思想却完全不同。"密码术"主要通过设计加密技术,使保密信息不可读,但是对于非授权者来讲,虽然他无法获知保密信息的具体内容,却能意识到保密信息的存在。而"匿形术"则致力于通过设计精妙的方法,使得非授权者根本无从得知保密信息的存在与否。相对于现代密码学来讲,信息隐藏的最大优势在于它并不限制对主信号的存取和访问,而是致力于签字信号的安全保密性。
我们来实践一个基于一阶Bézier曲线的信息隐藏编程实例 ,需要一定的数学基础,请见代码分析。
- #ifdef _DEBUG
- #define new DEBUG_NEW
- #undef THIS_FILE
- static char THIS_FILE[] = __FILE__;
- #endif
- /////////////////////////////////////////////////////////////////////////////
- // CAboutDlg dialog used for App About
- class CAboutDlg : public CDialog
- {
- public:
- CAboutDlg();
- // Dialog Data
- //{{AFX_DATA(CAboutDlg)
- enum { IDD = IDD_ABOUTBOX };
- //}}AFX_DATA
- // ClassWizard generated virtual function overrides
- //{{AFX_VIRTUAL(CAboutDlg)
- protected:
- virtual void DoDataExchange(CDataExchange* pDX); // DDX/DDV support
- //}}AFX_VIRTUAL
- // Implementation
- protected:
- //{{AFX_MSG(CAboutDlg)
- //}}AFX_MSG
- DECLARE_MESSAGE_MAP()
- };
- CAboutDlg::CAboutDlg() : CDialog(CAboutDlg::IDD)
- {
- //{{AFX_DATA_INIT(CAboutDlg)
- //}}AFX_DATA_INIT
- }
- void CAboutDlg::DoDataExchange(CDataExchange* pDX)
- {
- CDialog::DoDataExchange(pDX);
- //{{AFX_DATA_MAP(CAboutDlg)
- //}}AFX_DATA_MAP
- }
- BEGIN_MESSAGE_MAP(CAboutDlg, CDialog)
- //{{AFX_MSG_MAP(CAboutDlg)
- // No message handlers
- //}}AFX_MSG_MAP
- END_MESSAGE_MAP()
- /////////////////////////////////////////////////////////////////////////////
- // CDataHideInBMPBZDlg dialog
- CDataHideInBMPBZDlg::CDataHideInBMPBZDlg(CWnd* pParent /*=NULL*/)
- : CDialog(CDataHideInBMPBZDlg::IDD, pParent)
- {
- //{{AFX_DATA_INIT(CDataHideInBMPBZDlg)
- // NOTE: the ClassWizard will add member initialization here
- //}}AFX_DATA_INIT
- // Note that LoadIcon does not require a subsequent DestroyIcon in Win32
- m_hIcon = AfxGetApp()->LoadIcon(IDR_MAINFRAME);
- }
- void CDataHideInBMPBZDlg::DoDataExchange(CDataExchange* pDX)
- {
- CDialog::DoDataExchange(pDX);
- //{{AFX_DATA_MAP(CDataHideInBMPBZDlg)
- // NOTE: the ClassWizard will add DDX and DDV calls here
- //}}AFX_DATA_MAP
- }
- BEGIN_MESSAGE_MAP(CDataHideInBMPBZDlg, CDialog)
- //{{AFX_MSG_MAP(CDataHideInBMPBZDlg)
- ON_WM_SYSCOMMAND()
- ON_WM_PAINT()
- ON_WM_QUERYDRAGICON()
- ON_BN_CLICKED(IDC_BASEBMP_HIDE, OnBasebmpHide)
- ON_BN_CLICKED(IDC_HIDEFILE, OnHidefile)
- ON_BN_CLICKED(IDC_DOHIDE, OnDohide)
- ON_BN_CLICKED(IDC_BASEBMP_RESUME, OnBasebmpResume)
- ON_BN_CLICKED(IDC_BASEFILE, OnBasefile)
- ON_BN_CLICKED(IDC_RESUMEDATA, OnResumedata)
- //}}AFX_MSG_MAP
- END_MESSAGE_MAP()
- /////////////////////////////////////////////////////////////////////////////
- // CDataHideInBMPBZDlg message handlers
- BOOL CDataHideInBMPBZDlg::OnInitDialog()
- {
- CDialog::OnInitDialog();
- // Add "About..." menu item to system menu.
- // IDM_ABOUTBOX must be in the system command range.
- ASSERT((IDM_ABOUTBOX & 0xFFF0) == IDM_ABOUTBOX);
- ASSERT(IDM_ABOUTBOX < 0xF000);
- CMenu* pSysMenu = GetSystemMenu(FALSE);
- if (pSysMenu != NULL)
- {
- CString strAboutMenu;
- strAboutMenu.LoadString(IDS_ABOUTBOX);
- if (!strAboutMenu.IsEmpty())
- {
- pSysMenu->AppendMenu(MF_SEPARATOR);
- pSysMenu->AppendMenu(MF_STRING, IDM_ABOUTBOX, strAboutMenu);
- }
- }
- // Set the icon for this dialog. The framework does this automatically
- // when the application's main window is not a dialog
- SetIcon(m_hIcon, TRUE); // Set big icon
- SetIcon(m_hIcon, FALSE); // Set small icon
-
- // TODO: Add extra initialization here
- t=0.035; //融合系数
- m_bBaseBMPHide=false;
- m_bBaseBMPResume=false;
- m_bHidefile=false;
- m_bBasefile=false;
- GetDlgItem(IDC_DOHIDE)->EnableWindow(m_bBaseBMPHide && m_bHidefile);
- GetDlgItem(IDC_RESUMEDATA)->EnableWindow(m_bBaseBMPResume && m_bBasefile);
- return TRUE; // return TRUE unless you set the focus to a control
- }
- void CDataHideInBMPBZDlg::OnSysCommand(UINT nID, LPARAM lParam)
- {
- if ((nID & 0xFFF0) == IDM_ABOUTBOX)
- {
- CAboutDlg dlgAbout;
- dlgAbout.DoModal();
- }
- else
- {
- CDialog::OnSysCommand(nID, lParam);
- }
- }
- // If you add a minimize button to your dialog, you will need the code below
- // to draw the icon. For MFC applications using the document/view model,
- // this is automatically done for you by the framework.
- void CDataHideInBMPBZDlg::OnPaint()
- {
- if (IsIconic())
- {
- CPaintDC dc(this); // device context for painting
- SendMessage(WM_ICONERASEBKGND, (WPARAM) dc.GetSafeHdc(), 0);
- // Center icon in client rectangle
- int cxIcon = GetSystemMetrics(SM_CXICON);
- int cyIcon = GetSystemMetrics(SM_CYICON);
- CRect rect;
- GetClientRect(&rect);
- int x = (rect.Width() - cxIcon + 1) / 2;
- int y = (rect.Height() - cyIcon + 1) / 2;
- // Draw the icon
- dc.DrawIcon(x, y, m_hIcon);
- }
- else
- {
- CDialog::OnPaint();
- }
- }
- // The system calls this to obtain the cursor to display while the user drags
- // the minimized window.
- HCURSOR CDataHideInBMPBZDlg::OnQueryDragIcon()
- {
- return (HCURSOR) m_hIcon;
- }
- unsigned char CDataHideInBMPBZDlg::HideCalculate(unsigned char B, unsigned char H)
- {
- unsigned char R=(int)((1-t)*B+0.5f)+(int)(t*H+0.5f);
- return R;
- }
- unsigned char CDataHideInBMPBZDlg::ShowCalculate(unsigned char C, unsigned char B)
- {
- unsigned char R=(int)((C- (int)((1-t)*B+0.5f))/t+0.5f);
- if(R%32>15)
- R+=15;
- R=(int)(R/32.0f+0.5f);
- return R;
- }
- void CDataHideInBMPBZDlg::OnBasebmpHide()
- {
- // TODO: Add your control notification handler code here
- CFileDialog dlg(TRUE,"bmp","*.bmp",OFN_HIDEREADONLY|OFN_OVERWRITEPROMPT,"载体位图文件(*.bmp)|*.bmp||",NULL);
- if(dlg.DoModal()==IDOK)
- {
- m_bBaseBMPHide=true;
- m_sCarrierFileHide=dlg.GetPathName();
- GetDlgItem(IDC_BASEBMP_HIDE)->SetWindowText(m_sCarrierFileHide);
- }
- else
- m_bBaseBMPHide=false;
- GetDlgItem(IDC_DOHIDE)->EnableWindow(m_bBaseBMPHide && m_bHidefile);
- }
- void CDataHideInBMPBZDlg::OnHidefile()
- {
- // TODO: Add your control notification handler code here
- CFileDialog dlg(TRUE,"*","*.*",OFN_HIDEREADONLY|OFN_OVERWRITEPROMPT,"待隐藏文件(*.*)|*.*||",NULL);
- if(dlg.DoModal()==IDOK)
- {
- m_bHidefile=true;
- m_sHideFile=dlg.GetPathName();
- m_sHideFileName=dlg.GetFileName();
- GetDlgItem(IDC_HIDEFILE)->SetWindowText(m_sHideFileName);
- }
- else
- m_bHidefile=false;
- GetDlgItem(IDC_DOHIDE)->EnableWindow(m_bBaseBMPHide && m_bHidefile);
- }
- void CDataHideInBMPBZDlg::OnDohide()
- {
- // TODO: Add your control notification handler code here
- CFile BaseFile,HideFile;
- DWORD BaseFileLen,HideFileLen;
-
- unsigned char* BaseData;
- unsigned char* HideData;
-
- if(m_bBaseBMPHide==true && m_bHidefile==true)
- {
- BaseFile.Open(m_sCarrierFileHide,CFile::modeReadWrite);
- BaseFileLen=BaseFile.GetLength();
- HideFile.Open(m_sHideFile,CFile::modeReadWrite);
- HideFileLen=HideFile.GetLength();
-
- //信息头:文件名*文件长*
- CString InfoHead;
- InfoHead.Format("%s*%d*",m_sHideFileName,HideFileLen);
- int HeadLen=InfoHead.GetLength();
-
- if(BaseFileLen<((HeadLen+HideFileLen)*8)/3+100)
- {
- AfxMessageBox("待隐藏文件过大!请换一较大载体位图文件。");
- return;
- }
- BaseData=new unsigned char[BaseFileLen];
- BaseFile.Read(BaseData,BaseFileLen);
- HideData=new unsigned char[BaseFileLen];
- //对明文进行组帧
- for(int k=0;k<HeadLen;k++)
- HideData[k]=InfoHead.GetAt(k);
- HideFile.Read(HideData+HeadLen,HideFileLen);
- for(DWORD kk=HeadLen+HideFileLen;kk<BaseFileLen;kk++)
- HideData[kk]=0;
- if(BaseData[28]!=24)
- {
- AfxMessageBox("载体文件格式错误!");
- BaseFile.Close();
- if(BaseData!=NULL)
- delete BaseData;
- return;
- }
- unsigned char Temp=0;
- DWORD j=0;
- for(DWORD i=54;i<BaseFileLen;i++)
- {
- Temp=((HideData[j]&224)>>5)<<5; //1
- BaseData[i]=HideCalculate(BaseData[i],Temp);
- i++;
- Temp=((HideData[j]&28)>>2)<<5; //2
- BaseData[i]=HideCalculate(BaseData[i],Temp);
- i++;
- Temp=(HideData[j]&3)<<1; //3
- j++;
- Temp|=(HideData[j]&128)>>7;
- Temp*=32;
- BaseData[i]=HideCalculate(BaseData[i],Temp);
- i++;
- Temp=((HideData[j]&112)>>4)<<5; //4
- BaseData[i]=HideCalculate(BaseData[i],Temp);
- i++;
- Temp=((HideData[j]&14)>>1)<<5; //5
- BaseData[i]=HideCalculate(BaseData[i],Temp);
- i++;
- Temp=(HideData[j]&1)<<2; //6
- j++;
- Temp|=(HideData[j]&192)>>6;
- Temp*=32;
- BaseData[i]=HideCalculate(BaseData[i],Temp);
- i++;
- Temp=((HideData[j]&56)>>3)<<5; //7
- BaseData[i]=HideCalculate(BaseData[i],Temp);
- i++;
- Temp=(HideData[j]&7)<<5; //8
- BaseData[i]=HideCalculate(BaseData[i],Temp);
- j++;
- }
- BaseFile.Close();
- HideFile.Close();
-
- CFile file;
- file.Open("融合图像.bmp",CFile::modeCreate|CFile::modeReadWrite);
- file.Write(BaseData,BaseFileLen);
- file.Close();
- AfxMessageBox("信息隐藏完毕!");
-
- if(BaseData!=NULL)
- delete BaseData;
- if(HideData!=NULL)
- delete HideData;
- }
- }
- void CDataHideInBMPBZDlg::OnBasebmpResume()
- {
- // TODO: Add your control notification handler code here
- CFileDialog dlg(TRUE,"bmp","*.bmp",OFN_HIDEREADONLY|OFN_OVERWRITEPROMPT,"载体位图文件(*.bmp)|*.bmp||",NULL);
- if(dlg.DoModal()==IDOK)
- {
- m_bBaseBMPResume=true;
- m_sCarrierFileResume=dlg.GetPathName();
- GetDlgItem(IDC_BASEBMP_RESUME)->SetWindowText(m_sCarrierFileResume);
- }
- else
- m_bBaseBMPResume=false;
- GetDlgItem(IDC_RESUMEDATA)->EnableWindow(m_bBaseBMPResume && m_bBasefile);
- }
- void CDataHideInBMPBZDlg::OnBasefile()
- {
- // TODO: Add your control notification handler code here
- CFileDialog dlg(TRUE,"bmp","*.bmp",OFN_HIDEREADONLY|OFN_OVERWRITEPROMPT,"原始文件(*.bmp)|*.bmp||",NULL);
- if(dlg.DoModal()==IDOK)
- {
- m_bBasefile=true;
- m_sBaseFile=dlg.GetPathName();
- GetDlgItem(IDC_BASEFILE)->SetWindowText(m_sBaseFile);
- }
- else
- m_bBasefile=false;
- GetDlgItem(IDC_RESUMEDATA)->EnableWindow(m_bBaseBMPResume && m_bBasefile);
- }
- void CDataHideInBMPBZDlg::OnResumedata()
- {
- // TODO: Add your control notification handler code here
- CFile BaseFile;
- CFile CarrierFile;
- DWORD BaseFileLen;
- DWORD CarrierFileLen;
-
- unsigned char* BaseData;
- unsigned char* CarrierData;
-
- if(m_bBaseBMPResume==true && m_bBasefile==true)
- {
- CarrierFile.Open(m_sCarrierFileResume,CFile::modeReadWrite);
- CarrierFileLen=CarrierFile.GetLength();
- BaseFile.Open(m_sBaseFile,CFile::modeReadWrite);
- BaseFileLen=BaseFile.GetLength();
- if(BaseFileLen!=CarrierFileLen)
- {
- AfxMessageBox("选取的不是充作载体的原始文件!");
- CarrierFile.Close();
- BaseFile.Close();
- return;
- }
-
- CarrierData=new unsigned char[CarrierFileLen];
- CarrierFile.Read(CarrierData,CarrierFileLen);
- BaseData=new unsigned char[CarrierFileLen];
- BaseFile.Read(BaseData,CarrierFileLen);
- if(CarrierData[28]!=24)
- {
- AfxMessageBox("载体文件格式错误!");
- CarrierFile.Close();
- BaseFile.Close();
- if(CarrierData!=NULL)
- delete CarrierData;
- if(BaseData!=NULL)
- delete BaseData;
- return;
- }
- if(BaseData[28]!=24)
- {
- AfxMessageBox("原始文件格式错误!");
- CarrierFile.Close();
- BaseFile.Close();
- if(CarrierData!=NULL)
- delete CarrierData;
- if(BaseData!=NULL)
- delete BaseData;
- return;
- }
- unsigned char Temp=0;
- DWORD j=0;
- for(DWORD i=54;i<CarrierFileLen;i++)
- {
- Temp=(ShowCalculate(CarrierData[i],BaseData[i])&7)<<5;
- i++;
- Temp|=(ShowCalculate(CarrierData[i],BaseData[i])&7)<<2;
- i++;
- Temp|=(ShowCalculate(CarrierData[i],BaseData[i])&6)>>1;
- CarrierData[j]=Temp;
- j++;
- Temp=(ShowCalculate(CarrierData[i],BaseData[i])&1)<<7;
- i++;
- Temp|=(ShowCalculate(CarrierData[i],BaseData[i])&7)<<4;
- i++;
- Temp|=(ShowCalculate(CarrierData[i],BaseData[i])&7)<<1;
- i++;
- Temp|=(ShowCalculate(CarrierData[i],BaseData[i])&4)>>2;
- CarrierData[j]=Temp;
- j++;
- Temp=(ShowCalculate(CarrierData[i],BaseData[i])&3)<<6;
- i++;
- Temp|=(ShowCalculate(CarrierData[i],BaseData[i])&7)<<3;
- i++;
- Temp|=ShowCalculate(CarrierData[i],BaseData[i])&7;
- CarrierData[j]=Temp;
- j++;
- }
- BaseFile.Close();
- CarrierFile.Close();
- j=0;
- CString FileName="";
- while(true)
- {
- if(CarrierData[j]=='*')
- {
- j++;
- break;
- }
- else
- {
- FileName+=CString(CarrierData[j]);
- j++;
- }
- }
- CString FileLen="";
- while(true)
- {
- if(CarrierData[j]=='*')
- {
- j++;
- break;
- }
- else
- {
- FileLen+=CString(CarrierData[j]);
- j++;
- }
- }
- BaseFileLen=atoi(FileLen);
- CFile file;
- file.Open(FileName,CFile::modeCreate|CFile::modeReadWrite);
- file.Write(CarrierData+j,BaseFileLen);
- file.Close();
- AfxMessageBox("信息恢复完毕!");
- if(BaseData!=NULL)
- delete BaseData;
- if(CarrierData!=NULL)
- delete CarrierData;
- }
- }
复制代码 作者:yincheng01 发表于2011-12-15 7:46:03 原文链接
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