Retrieving Media File Information for C++

This simple C++ example for using the ltmmMediaInfo object retrieves the source file properties and displays them in message boxes.

#include "ltmm.h"

#include <atlbase.h>

#include <atlconv.h>



void AddStringToMsg(char *pszTitle, BSTR sString, char *pszMsg);

void AddNumberToMsg(char *pszTitle, double dNumber, char *pszMsg, BOOL 
 bFloat);



int main()

{

   IltmmMediaInfo *pMediaInfo;

   BSTR sString;

   char szMsg[8196];

   long lStreams, lIndex, l;

   double d;



   CoInitialize(NULL);



   // create an ltmmMediaInfo object: 

   HRESULT hr = CoCreateInstance(CLSID_ltmmMediaInfo, NULL,

                                 
 CLSCTX_INPROC_SERVER, IID_IltmmMediaInfo,

               
                   (void**) 
 &pMediaInfo);



   memset(szMsg, 0, 8196);



   // set the source file: 

   sString = SysAllocString(L"C:\\Test.avi");

   pMediaInfo->put_SourceFile(sString);

   SysFreeString(sString);



   // general properties: 

   pMediaInfo->get_SourceFile(&sString);

   AddStringToMsg("Source file: ", sString, szMsg);

   SysFreeString(sString);



   pMediaInfo->get_SourceFileSize(&d);

   AddNumberToMsg("File size: ", d, szMsg, FALSE);



   pMediaInfo->get_OutputStreams(&lStreams);

   AddNumberToMsg("Number of streams: ", (double)lStreams, 
 szMsg, FALSE);



   pMediaInfo->get_SourceDuration(&d);

   AddNumberToMsg("File duration: ", d, szMsg, TRUE);



   pMediaInfo->get_SourceBitRate(&l);

   AddNumberToMsg("Source BitRate : ", (double)l, szMsg, 
 FALSE);



   pMediaInfo->get_SourceFormat(&l);

   AddNumberToMsg("Source format: ", (double)l, szMsg, 
 FALSE);



   pMediaInfo->get_SourceFormatName(&sString);

   AddStringToMsg("Source format name: ", sString, 
 szMsg);

   SysFreeString(sString);



   pMediaInfo->get_SourceFilterClassID(&sString);

   AddStringToMsg("Source filter CLSID: ", sString, 
 szMsg);

   SysFreeString(sString);



   pMediaInfo->get_SourceFilterName(&sString);

   AddStringToMsg("Source filter name: ", sString, 
 szMsg);

   SysFreeString(sString);



   pMediaInfo->get_Title(&sString);

   AddStringToMsg("Title   The name for a group of related video files (called "Chapters") on your DVD. For example, for a DVD called "My Summer Vacation," you might have the titles "Water Skiing," "New Friends," and "Hiking." For each of those titles, you might have one or more different video files.: ", sString, szMsg);

   SysFreeString(sString);



   pMediaInfo->get_Author(&sString);

   AddStringToMsg("Author: ", sString, szMsg);

   SysFreeString(sString);



   pMediaInfo->get_Description(&sString);

   AddStringToMsg("Description: ", sString, szMsg);

   SysFreeString(sString);



   pMediaInfo->get_Rating(&sString);

   AddStringToMsg("Rating: ", sString, szMsg);

   SysFreeString(sString);



   pMediaInfo->get_Copyright(&sString);

   AddStringToMsg("Copyright: ", sString, szMsg);

   SysFreeString(sString);



   MessageBox(0, szMsg, "MediaInfo Sample: General...", 
 0);



   // stream properties: 

   for( lIndex=0; lIndex<lStreams; lIndex++ )

   {

      memset(szMsg, 0, 8196);



      pMediaInfo->put_CurrentStream(lIndex);



      pMediaInfo->get_CurrentStream(&l);

      AddNumberToMsg("Stream number: ", 
 (double)l, szMsg, FALSE);



      pMediaInfo->get_StreamType(&sString);

      AddStringToMsg("Stream type: ", 
 sString, szMsg);

      SysFreeString(sString);



      pMediaInfo->get_StreamTypeName(&sString);

      AddStringToMsg("Stream type name: ", 
 sString, szMsg);

      SysFreeString(sString);



      pMediaInfo->get_StreamSubtype(&sString);

      AddStringToMsg("Stream subtype: ", 
 sString, szMsg);

      SysFreeString(sString);



      pMediaInfo->get_StreamSubtypeName(&sString);

      AddStringToMsg("Stream subtype name: 
 ", sString, szMsg);

      SysFreeString(sString);



      pMediaInfo->get_StreamDuration(&d);

      AddNumberToMsg("Stream duration: ", 
 d, szMsg, TRUE);



      // video specific 

      strcat(szMsg, "\n");

      strcat(szMsg, "\t*** Video specific 
 properties ***\n");



      pMediaInfo->get_VideoFrameRate(&d);

      AddNumberToMsg("Video frame rate: ", 
 d, szMsg, TRUE);



      pMediaInfo->get_VideoWidth(&l);

      AddNumberToMsg("Video width: ", 
 (double)l, szMsg, FALSE);



      pMediaInfo->get_VideoHeight(&l);

      AddNumberToMsg("Video height: ", 
 (double)l, szMsg, FALSE);



      pMediaInfo->get_VideoBitCount(&l);

      AddNumberToMsg("Video bit count: ", 
 (double)l, szMsg, FALSE);



      pMediaInfo->get_VideoCompression(&l);

      AddNumberToMsg("Video compression: 
 ", (double)l, szMsg, FALSE);



      pMediaInfo->get_VideoBitRate(&l);

      AddNumberToMsg("Video bit rate: ", 
 (double)l, szMsg, FALSE);



      pMediaInfo->get_VideoFrames(&l);

      AddNumberToMsg("Video frames count: 
 ", (double)l, szMsg, FALSE);



      // Audio specific 

      strcat(szMsg, "\n");

      strcat(szMsg, "\t*** Audio specific 
 properties ***\n");



      pMediaInfo->get_AudioFormatTag(&l);

      AddNumberToMsg("Audio format tag: ", 
 (double)l, szMsg, FALSE);



      pMediaInfo->get_AudioChannels(&l);

      AddNumberToMsg("Audio channels: ", 
 (double)l, szMsg, FALSE);



      pMediaInfo->get_AudioSamplesPerSec(&l);

      AddNumberToMsg("Audio frequency: ", 
 (double)l, szMsg, FALSE);



      pMediaInfo->get_AudioBitsPerSample(&l);

      AddNumberToMsg("Audio sample size: 
 ", (double)l, szMsg, FALSE);



      pMediaInfo->get_AudioAvgBytesPerSec(&l);

      AddNumberToMsg("Audio average bytes 
 per second: ", (double)l, szMsg, FALSE);



      MessageBox(0, szMsg, "MediaInfo Sample: 
 Streams...", 0);

   }





   pMediaInfo->ResetSource();

   pMediaInfo->Release();



   CoUninitialize();

                
 return 0;

}



void AddStringToMsg(char *pszTitle, BSTR sString, char *pszMsg)

{

   USES_CONVERSION;



   strcat(pszMsg, pszTitle);

   if( sString )

      strcat(pszMsg, W2A(sString));

   else

      strcat(pszMsg, "NA");

   strcat(pszMsg, " \n");

}



void AddNumberToMsg(char *pszTitle, double dNumber, char *pszMsg, BOOL 
 bFloat)

{

   char szNumber[64];



   if( bFloat )

      sprintf(szNumber, "%f", dNumber);

   else

      sprintf(szNumber, "%.f", dNumber);



   strcat(pszMsg, pszTitle);

   strcat(pszMsg, szNumber);

   strcat(pszMsg, " \n");

}