PLUGIN ECHO POUR WINAMP

#include <stdio.h>
#include <windows.h>
#include <commctrl.h>
#include "dsp.h"
#include "resource.h"

#define NB_ECHO_BUFFERS 10 // 

BOOL WINAPI _DllMainCRTStartup(HANDLE hInst, ULONG ul_reason_for_call, LPVOID lpReserved)
{
 return TRUE;
}

HWND echo_control_hwnd;

int quit_echo=0;

winampDSPModule *getModule(int which);

void config(struct winampDSPModule *this_mod);
int initecho(struct winampDSPModule *this_mod);
void quitecho(struct winampDSPModule *this_mod);
int modify_samples1(struct winampDSPModule *this_mod, short int *samples, int numsamples, int bps, int nch, int srate);

static BOOL CALLBACK echoProc (HWND hwndDlg, UINT uMsg, WPARAM wParam,LPARAM lParam);

winampDSPHeader hdr = { DSP_HDRVER, "Nullsoft DSP demo v0.3 for Winamp 2", getModule };

int volume_general;
int gain_echo_L1;
int gain_echo_R1;
short echo1_actif = 1;

//****************************************************************************

winampDSPModule mod =
{
 "echo",
 NULL,	// hwndParent
 NULL,	// hDllInstance
 config,
 initecho,
 modify_samples1,
 quitecho
};

//****************************************************************************

#ifdef __cplusplus
extern "C" {
#endif

__declspec( dllexport ) winampDSPHeader *winampDSPGetHeader2()
{
 return &hdr;
}
#ifdef __cplusplus
}
#endif

//****************************************************************************

winampDSPModule *getModule(int which)
{
  switch (which)
   {
    case 0: return &mod;
    default:return NULL;
   }
}

//****************************************************************************

void config(struct winampDSPModule *this_mod)
{
 MessageBox(this_mod->hwndParent,"Rock'n'roll :)","Configuration",MB_OK);
}

//****************************************************************************

// initialisation du module
int initecho(struct winampDSPModule *this_mod)
{
 quit_echo=0;		
 ShowWindow((echo_control_hwnd=CreateDialog(this_mod->hDllInstance,MAKEINTRESOURCE(IDD_DIALOG1),this_mod->hwndParent,echoProc)),SW_SHOW); 
 return 0;
}

//****************************************************************************

// fonction quit du module
void quitecho(struct winampDSPModule *this_mod)
{
 if (this_mod == &mod)
  {
   quit_echo=1;
   if (echo_control_hwnd)
    {
     DestroyWindow(echo_control_hwnd);
     echo_control_hwnd=0;
    }
  }
}

//****************************************************************************

int modify_samples1(struct winampDSPModule *this_mod, short int *samples, int numsamples, int bps, int nch, int srate)
 {
  static short buffer[NB_ECHO_BUFFERS][4096];
  static int i,j;

  if (bps == 16 && nch == 2)
   {

    // mettre le bloc entrant dans le dernier bloc du buffer
    for (i = 0; i < numsamples*nch; i+=2)
     {
      buffer[NB_ECHO_BUFFERS-1][i]   = samples[i];   // voie gauche
      buffer[NB_ECHO_BUFFERS-1][i+1] = samples[i+1]; // voie droite
     }


    // calculer l'echo avec le premier bloc et le bloc entrant
    for (i = 0; i < numsamples*nch; i+=2)
     {
      samples[i]   = buffer[0][i]   * echo1_actif * gain_echo_L1/100 + buffer[NB_ECHO_BUFFERS-1][i];   // voie gauche
      samples[i+1] = buffer[0][i+1] * echo1_actif * gain_echo_R1/100 + buffer[NB_ECHO_BUFFERS-1][i+1]; // voie droite
     }


    // volume general
    for (i = 0; i < numsamples*nch; i+=2)
     {
      samples[i]   = samples[i]   * volume_general/100; // voie gauche
      samples[i+1] = samples[i+1] * volume_general/100; // voie droite
     } 


    // memoriser le bloc sortant
    for (i = 0; i < numsamples*nch; i+=2)
     {
      buffer[NB_ECHO_BUFFERS-1][i]   = samples[i];   // voie gauche
      buffer[NB_ECHO_BUFFERS-1][i+1] = samples[i+1]; // voie droite
     }


    // decaler tous les blocs vers la gauche pour laisser la place au prochain bloc entrant    
    for (j = 0; j < NB_ECHO_BUFFERS-1; j++)    
     {
      for (i = 0; i < numsamples*nch; i+=2)
       {
        buffer[j][i]   = buffer[j+1][i];   // voie gauche
        buffer[j][i+1] = buffer[j+1][i+1]; // voie droite
       }
     }
   }

  return numsamples;
}


//****************************************************************************

// procedure fenetre echo
static BOOL CALLBACK echoProc(HWND hwndDlg, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
  
  if (uMsg == WM_DESTROY)
   {
   }
   
  if (uMsg == WM_COMMAND)
   {
    if(wParam == IDC_CHECK1)
     {
      if (IsDlgButtonChecked(hwndDlg , IDC_CHECK1) == BST_UNCHECKED)
       {
        SetDlgItemText(hwndDlg, IDC_CHECK1, "OFF");
        echo1_actif = 0;
       }
      if (IsDlgButtonChecked(hwndDlg , IDC_CHECK1) == BST_CHECKED)
       {
        SetDlgItemText(hwndDlg, IDC_CHECK1, "ON");
        echo1_actif = 1;
       }
     }
   }


  if (uMsg == WM_INITDIALOG)
   {    
    SetWindowPos(hwndDlg, HWND_TOP, 0, 0, 0, 0, SWP_NOSIZE); // positionner la fenetre en haut a gauche
        
    CheckDlgButton(hwndDlg, IDC_CHECK1, TRUE); // echo actif au demarrage
    SetDlgItemText(hwndDlg, IDC_CHECK1, "ON");

    SendDlgItemMessage(hwndDlg,IDC_SLIDER_VOLUME_GENERAL,TBM_SETRANGEMAX,0,100); // volume general a fond
    SendDlgItemMessage(hwndDlg,IDC_SLIDER_VOLUME_GENERAL,TBM_SETRANGEMIN,0,0);
    SendDlgItemMessage(hwndDlg,IDC_SLIDER_VOLUME_GENERAL,TBM_SETPOS,1,0);
    volume_general = 100-SendDlgItemMessage(hwndDlg,IDC_SLIDER_VOLUME_GENERAL,TBM_GETPOS,0,0);
     {
      char str[8];
      wsprintf(str,"%d",volume_general);
      SetDlgItemText(hwndDlg,IDC_STATIC_VOLUME_GENERAL,str);
     }

    SendDlgItemMessage(hwndDlg,IDC_SLIDER_GAINL1,TBM_SETRANGEMAX,0,100);
    SendDlgItemMessage(hwndDlg,IDC_SLIDER_GAINL1,TBM_SETRANGEMIN,0,0);
    SendDlgItemMessage(hwndDlg,IDC_SLIDER_GAINL1,TBM_SETPOS,1,50);
    gain_echo_L1 = 100-SendDlgItemMessage(hwndDlg,IDC_SLIDER_GAINL1,TBM_GETPOS,0,0);
     {
      char str[8];
      wsprintf(str,"%d",gain_echo_L1);
      SetDlgItemText(hwndDlg,IDC_STATIC_GAINL1,str);
     }

    SendDlgItemMessage(hwndDlg,IDC_SLIDER_GAINR1,TBM_SETRANGEMAX,0,100);
    SendDlgItemMessage(hwndDlg,IDC_SLIDER_GAINR1,TBM_SETRANGEMIN,0,0);
    SendDlgItemMessage(hwndDlg,IDC_SLIDER_GAINR1,TBM_SETPOS,1,50);
    gain_echo_R1 = 100-SendDlgItemMessage(hwndDlg,IDC_SLIDER_GAINR1,TBM_GETPOS,0,0);
     {
      char str[8];
      wsprintf(str,"%d",gain_echo_R1);
      SetDlgItemText(hwndDlg,IDC_STATIC_GAINR1,str);
     }
   }




  if (uMsg == WM_VSCROLL)
   {
    volume_general = 100-SendDlgItemMessage(hwndDlg,IDC_SLIDER_VOLUME_GENERAL,TBM_GETPOS,0,0);
     {
      char str[8];
      wsprintf(str,"%d",volume_general);
      SetDlgItemText(hwndDlg,IDC_STATIC_VOLUME_GENERAL,str);
     }    
    gain_echo_L1 = 100-SendDlgItemMessage(hwndDlg,IDC_SLIDER_GAINL1,TBM_GETPOS,0,0);
     {
      char str[8];
      wsprintf(str,"%d",gain_echo_L1);
      SetDlgItemText(hwndDlg,IDC_STATIC_GAINL1,str);
     }
    gain_echo_R1 = 100-SendDlgItemMessage(hwndDlg,IDC_SLIDER_GAINR1,TBM_GETPOS,0,0);
     {
      char str[8];
      wsprintf(str,"%d",gain_echo_R1);
      SetDlgItemText(hwndDlg,IDC_STATIC_GAINR1,str);
     }
   }





return 0;
}

//****************************************************************************