The VideoLAN Forums

Posted: **13 Oct 2009 09:34**

Hello !

I try to use libvlc.dll to send the video of my webcam to a vlc application.

I use the exemple given here : http://wiki.videolan.org/LibVLC_Visual_C

vlc.h

Code: Select all

#ifndef _INTERFAZ_LIB_VLC_21_NOV_2006
#define _INTERFAZ_LIB_VLC_21_NOV_2006
#include <windows.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <map>
using namespace std;
// Definición de las constantes de VLC
#define VLC_SUCCESS         0         // Sin error
#define VLC_ENOMEM         -1         // Memoria insuficiente
#define VLC_ETHREAD         -2         // Error de Thread
#define VLC_ETIMEOUT      -3         // Fuera de tiempo
#define VLC_ENOMOD         -10         // Módulo no localizado
#define VLC_ENOOBJ         -20         // Objeto no encontrado
#define VLC_EBADOBJ         -21         // Tipo de objeto inadecuado
#define VLC_ENOVAR         -30         // Variable no encontrada
#define VLC_EBADVAR         -31         // Valor de variable erróneo
#define VLC_EEXIT         -255      // El programa finalizó
#define VLC_EEXITSUCCESS   -999      // Se salió del programa con éxito
#define VLC_EGENERIC      -666      // Error genérico
#define VLC_FALSE         0   
#define VLC_TRUE         1
#define PLAYLIST_INSERT      1
#define PLAYLIST_APPEND      2
#define PLAYLIST_GO         4
#define PLAYLIST_PREPARSE   8
#define PLAYLIST_END      -666
#define EXITO            0
#define NO_LIB            -1
#define NO_ENCONTRADO      -2
#define FUNCION_FALLA      -3

#define 	VLC_PUBLIC_API   extern
#define 	VLC_DEPRECATED_API   VLC_PUBLIC_API

// Definición de tipos propios de VLC
typedef int vlc_bool_t;
typedef struct vlc_list_t vlc_list_t;
typedef struct vlc_object_t vlc_object_t;
typedef signed __int64 vlc_int64_t;
typedef union{
   int             i_int;
   vlc_bool_t      b_bool;
   float           f_float;
   char *          psz_string;
   void *          p_address;
   vlc_object_t *   p_object;
   vlc_list_t *    p_list;
   vlc_int64_t     i_time;
   
   struct {
      char *psz_name;
      int i_object_id;
   } var;
   /* Make sure the structure is at least 64bits */
   struct { char a, b, c, d, e, f, g, h; } padding;
} vlc_value_t;
typedef const char * (*_VLC_VERSION)(void);
typedef const char * (*_VLC_ERROR)(int);
typedef int (*_VLC_CREATE)(void);
typedef int (*_VLC_INIT)(int, int, char **);
typedef int (*_VLC_ADDINTF)(int, const char *, vlc_bool_t, vlc_bool_t);
typedef int (*_VLC_DIE)(int);
typedef int (*_VLC_CLEANUP)(int);
typedef int (*_VLC_DESTROY)(int);
typedef int (*_VLC_VARIABLESET)(int, char const *, vlc_value_t);
typedef int (*_VLC_VARIABLEGET)(int, char const *, vlc_value_t *);
typedef int (*_VLC_VARIABLETYPE)(int, char const *, int *);
typedef int (*_VLC_ADDTARGET)(int, char const *, char const **, int, int, int);
typedef int (*_VLC_PLAY)(int);
typedef int (*_VLC_PAUSE)(int);
typedef int (*_VLC_STOP)(int);
typedef vlc_bool_t (*_VLC_ISPLAYING)(int);
typedef float (*_VLC_POSITIONGET)(int);
typedef float (*_VLC_POSITIONSET)(int, float);
typedef int (*_VLC_TIMEGET)(int);
typedef int (*_VLC_TIMESET)(int, int, vlc_bool_t);
typedef int (*_VLC_LENGTHGET)(int);
typedef float (*_VLC_SPEEDFASTER)(int);
typedef float (*_VLC_SPEEDSLOWER)(int);
typedef int (*_VLC_PLAYLISTINDEX)(int);
typedef int (*_VLC_PLAYLISTNUMBEROFITEMS)(int);
typedef int (*_VLC_PLAYLISTNEXT)(int);
typedef int (*_VLC_PLAYLISTPREV)(int);
typedef int (*_VLC_PLAYLISTCLEAR)(int);
typedef int (*_VLC_VOLUMESET)(int, int);
typedef int (*_VLC_VOLUMEGET)(int);
typedef int (*_VLC_VOLUMEMUTE)(int);
typedef int (*_VLC_FULLSCREEN)(int);

// Definición de variables globales para acceder a las funciones
_VLC_VERSION VLC_Version;
_VLC_ERROR VLC_Error;
_VLC_CREATE VLC_Create;
_VLC_INIT VLC_Init;
_VLC_ADDINTF VLC_AddIntf;
_VLC_DIE VLC_Die;
_VLC_CLEANUP VLC_CleanUp;
_VLC_DESTROY VLC_Destroy;
_VLC_VARIABLESET VLC_VariableSet;
_VLC_VARIABLEGET VLC_VariableGet;
_VLC_VARIABLETYPE VLC_VariableType;
_VLC_ADDTARGET VLC_AddTarget;
_VLC_PLAY VLC_Play;
_VLC_PAUSE VLC_Pause;
_VLC_STOP VLC_Stop;
_VLC_ISPLAYING VLC_IsPlaying;
_VLC_POSITIONGET VLC_PositionGet;
_VLC_POSITIONSET VLC_PositionSet;
_VLC_TIMEGET VLC_TimeGet;
_VLC_TIMESET VLC_TimeSet;
_VLC_LENGTHGET VLC_LengthGet;
_VLC_SPEEDFASTER VLC_SpeedFaster;
_VLC_SPEEDSLOWER VLC_SpeedSlower;
_VLC_PLAYLISTINDEX VLC_PlaylistIndex;
_VLC_PLAYLISTNUMBEROFITEMS VLC_PlaylistNumberOfItems;
_VLC_PLAYLISTNEXT VLC_PlaylistNext;
_VLC_PLAYLISTPREV VLC_PlaylistPrev;
_VLC_PLAYLISTCLEAR VLC_PlaylistClear;
_VLC_VOLUMESET VLC_VolumeSet;
_VLC_VOLUMEGET VLC_VolumeGet;
_VLC_VOLUMEMUTE VLC_VolumeMute;
_VLC_FULLSCREEN VLC_FullScreen;

HINSTANCE libvlc;

#endif

testvlc.cpp :

Code: Select all

#include "stdafx.h"
#include <string.h>
#include "dshow.h"
#include <stdio.h>
#include "malloc.h"
#include "vlc.h"
#include "windows.h"


/**********************************************************************
 * loadLibrary: Carga la librería VLC
 **********************************************************************/
int loadLibrary(LPWSTR libreria) {   
   LPCWSTR lib = L"C:\\Program Files\\VideoLAN\\VLC\\libvlc.dll";
   DWORD tamano = GetCurrentDirectoryW(0, NULL);
   int liblen = lstrlenW(lib);

   printf("Tamano: %d, %d\n", tamano, liblen);   
   LPWSTR buffer = new WCHAR[tamano + liblen];
   tamano = GetCurrentDirectoryW(tamano, buffer);
  buffer[tamano] = 0;   
   lstrcatW(buffer, lib);
   printf("Buffer: %S\n", buffer);   
   
   if (libvlc == NULL) {
      libvlc = LoadLibraryW(libreria);   
     
	   printf("On vient de tenter de changer la librairie\n"); 
	  delete buffer;
   }
   if (libvlc != NULL) {
       printf("librarie chargée\n"); 
	   return EXITO;
      delete buffer;
   } else {
      printf("Libreria libvlc.dll no encontrada, %d\n", GetLastError());
      return NO_LIB;
      delete buffer;
   }
}

/**********************************************************************
 * freeLibrary: Libera la librería VLC
 **********************************************************************/
bool freeLibrary() {
   BOOL libera = false;
   if (libvlc != NULL) {
      printf("Liberando libreria libvlc.dll\n");
      libera = FreeLibrary(libvlc);
      if (!libera) {
         printf("Error al liberar\n");
      }
   }
   return (libera == VLC_TRUE);
}

/**********************************************************************
 * funcionFalla: Muestra un mensaje si una función no puede ser
 * obtenida desde la DLL
 **********************************************************************/
inline int funcionFalla(const char * msg) {
   printf("La funcion %s no pudo inicializarse\n", msg);
   freeLibrary();
   return FUNCION_FALLA;
}

/**********************************************************************
 * initLib: Carga todas las funciones desde la librería
 **********************************************************************/
int initLib(LPWSTR libreria) {

   if (libvlc == NULL) {
      if (loadLibrary(libreria) != EXITO) {
         return NO_LIB;
      }         
   }
 printf("librairie chargé *2\n"); 
   if ((VLC_Version = (_VLC_VERSION) GetProcAddress(libvlc, "VLC_Version")) == NULL)
      return funcionFalla("VLC_Version");
   if ((VLC_AddIntf = (_VLC_ADDINTF) GetProcAddress(libvlc, "VLC_AddIntf")) == NULL)
      return funcionFalla("VLC_AddIntf");
   if ((VLC_AddTarget = (_VLC_ADDTARGET) GetProcAddress(libvlc, "VLC_AddTarget")) == NULL)
      return funcionFalla("VLC_AddTarget");
   if ((VLC_CleanUp = (_VLC_CLEANUP) GetProcAddress(libvlc, "VLC_CleanUp")) == NULL)
      return funcionFalla("VLC_CleanUp");
   if ((VLC_Create = (_VLC_CREATE) GetProcAddress(libvlc, "VLC_Create")) == NULL)
      return funcionFalla("VLC_Create");
   if ((VLC_Destroy = (_VLC_DESTROY) GetProcAddress(libvlc, "VLC_Destroy")) == NULL)
      return funcionFalla("VLC_Destroy");
   if ((VLC_Die = (_VLC_DIE) GetProcAddress(libvlc, "VLC_Die")) == NULL)
      return funcionFalla("VLC_Die");
   if ((VLC_Error = (_VLC_ERROR) GetProcAddress(libvlc, "VLC_Error")) == NULL)
      return funcionFalla("VLC_Error");
   if ((VLC_FullScreen = (_VLC_FULLSCREEN) GetProcAddress(libvlc, "VLC_FullScreen")) == NULL)
      return funcionFalla("VLC_FullScreen");
   if ((VLC_Init = (_VLC_INIT) GetProcAddress(libvlc, "VLC_Init")) == NULL)
      return funcionFalla("VLC_Init");
   if ((VLC_IsPlaying = (_VLC_ISPLAYING) GetProcAddress(libvlc, "VLC_IsPlaying")) == NULL)
      return funcionFalla("VLC_IsPlaying");
   if ((VLC_LengthGet = (_VLC_LENGTHGET) GetProcAddress(libvlc, "VLC_LengthGet")) == NULL)
      return funcionFalla("VLC_LengthGet");
   if ((VLC_Pause = (_VLC_PAUSE) GetProcAddress(libvlc, "VLC_Pause")) == NULL)
      return funcionFalla("VLC_Pause");
   if ((VLC_Play = (_VLC_PLAY) GetProcAddress(libvlc, "VLC_Play")) == NULL)
      return funcionFalla("VLC_Play");
   if ((VLC_PlaylistClear = (_VLC_PLAYLISTCLEAR) GetProcAddress(libvlc, "VLC_PlaylistClear")) == NULL)
      return funcionFalla("VLC_PlaylistClear");
   if ((VLC_PlaylistIndex = (_VLC_PLAYLISTINDEX) GetProcAddress(libvlc, "VLC_PlaylistIndex")) == NULL)
      return funcionFalla("VLC_PlaylistIndex");
   if ((VLC_PlaylistNext = (_VLC_PLAYLISTNEXT) GetProcAddress(libvlc, "VLC_PlaylistNext")) == NULL)
      return funcionFalla("VLC_PlaylistNext");
   if ((VLC_PlaylistNumberOfItems = (_VLC_PLAYLISTNUMBEROFITEMS) GetProcAddress(libvlc, "VLC_PlaylistNumberOfItems")) == NULL)
      return funcionFalla("VLC_PlaylistNumberOfItems");
   if ((VLC_PlaylistPrev = (_VLC_PLAYLISTPREV) GetProcAddress(libvlc, "VLC_PlaylistPrev")) == NULL)
      return funcionFalla("VLC_PlaylistPrev");
   if ((VLC_PositionGet = (_VLC_POSITIONGET) GetProcAddress(libvlc, "VLC_PositionGet")) == NULL)
      return funcionFalla("VLC_PositionGet");
   if ((VLC_PositionSet = (_VLC_POSITIONSET) GetProcAddress(libvlc, "VLC_PositionSet")) == NULL)
      return funcionFalla("VLC_PositionSet");
   if ((VLC_SpeedFaster = (_VLC_SPEEDFASTER) GetProcAddress(libvlc, "VLC_SpeedFaster")) == NULL)
      return funcionFalla("VLC_SpeedFaster");
   if ((VLC_SpeedSlower = (_VLC_SPEEDSLOWER) GetProcAddress(libvlc, "VLC_SpeedSlower")) == NULL)
      return funcionFalla("VLC_SpeedSlower");
   if ((VLC_Stop = (_VLC_STOP) GetProcAddress(libvlc, "VLC_Stop")) == NULL)
      return funcionFalla("VLC_Stop");
   if ((VLC_TimeGet = (_VLC_TIMEGET) GetProcAddress(libvlc, "VLC_TimeGet")) == NULL)
      return funcionFalla("VLC_TimeGet");
   if ((VLC_TimeSet = (_VLC_TIMESET) GetProcAddress(libvlc, "VLC_TimeSet")) == NULL)
      return funcionFalla("VLC_TimeSet");
   if ((VLC_VariableGet = (_VLC_VARIABLEGET) GetProcAddress(libvlc, "VLC_VariableGet")) == NULL)
      return funcionFalla("VLC_VariableGet");
   if ((VLC_VariableSet = (_VLC_VARIABLESET) GetProcAddress(libvlc, "VLC_VariableSet")) == NULL)
      return funcionFalla("VLC_VariableSet");
   if ((VLC_VariableType = (_VLC_VARIABLETYPE) GetProcAddress(libvlc, "VLC_VariableType")) == NULL)
      return funcionFalla("VLC_VariableType");
 
   if ((VLC_VolumeGet = (_VLC_VOLUMEGET) GetProcAddress(libvlc, "VLC_VolumeGet")) == NULL)
      return funcionFalla("VLC_VolumeGet");
   if ((VLC_VolumeMute = (_VLC_VOLUMEMUTE) GetProcAddress(libvlc, "VLC_VolumeMute")) == NULL)
      return funcionFalla("VLC_VolumeMute");
   if ((VLC_VolumeSet = (_VLC_VOLUMESET) GetProcAddress(libvlc, "VLC_VolumeSet")) == NULL)
      return funcionFalla("VLC_VolumeSet");
   return EXITO;
}

/**********************************************************************
 * verError: Muestra un mensaje de error
 **********************************************************************/
void getError(int error) {
   fprintf(stderr, "Error: %s\n", (VLC_Error)(error));
} 


// Main
int main(int argc, char * argv[]) {

	int i;
   if (initLib(L"C:\\Program Files\\VideoLAN\\VLC\\libvlc.dll") != EXITO) {
      printf("impossible de charger la librarie\n");
     Sleep(5000);
	  return -1;
   }
     

   int id = -1;

   // It creates the VLC instance
    int i_ret = (VLC_Create)();
    if( i_ret < 0 ) {
      getError(i_ret);
        return i_ret;
    }   

   id = i_ret;
 
   // Inits the instance
 
  
   char ** commands = new char*[6];
   commands[0] = "testvlcconsole.exe";
   commands[1] = "dshow://";
   commands[2] = ":dshow-vdev=Logitech QuickCam Pro 3000 (08B0)";
   commands[3] = ":dshow-adev=";
   commands[4] = ":dshow-size=176x144";
   commands[5] = ":sout=#transcode{vcodec=h264,vb=1024,scale=1}:duplicate{dst=rtp{mux=ts,dst=192.168.0.155,port=1234}}";


    i_ret = (VLC_Init)(id, 6, commands );
   printf("%d\n", i_ret);
    if( i_ret < 0 ) {
      getError(i_ret);
        (VLC_Destroy)( id );
        return -1;
    }   

    // Start playing
    i_ret = (VLC_Play)(id);
   if( i_ret < 0 ) {
      getError(i_ret);
      return false;
   }
   
   getchar();

   while((VLC_IsPlaying)(id));
   (VLC_Die)(id);
   (VLC_CleanUp)(id);
   (VLC_Destroy)(id);
   freeLibrary();
   return 0;   
}

But I have somes problems :

this ligne return a "NULL" ( and all next too ...)
(VLC_Version = (_VLC_VERSION) GetProcAddress(libvlc, "VLC_Version")

Maybe it's because prefix of the fonction are not correct ?? ( http://www.videolan.org/developers/vlc/ ... __old.html )

I don't know what i have to do , how to implement it ...

sorry for my bad english

goffle

Posted: **13 Oct 2009 17:14**

As the page says, this uses the old API. No wonder it's not working with newer DLLs.

The VideoLAN Forums

using libvlc.dll

using libvlc.dll

Re: using libvlc.dll