The following example shows how to capture a bitmap from video.

   USHORT usUserParm = 0;
   BITMAPINFOHEADER2 *pBMPhdr;
   ULONG   ulReturn;
   CHAR    szInfoStr[500];
   CHAR    szTempStr[100];
   ULONG   ulFlags = 0;

      ulFlags = MCI_CONVERT;

   /**********************************************************/
   /* Determine the length and characteristics of the buffer */
   /**********************************************************/
   memset ((PVOID)&mciImageParms, 0x00, sizeof (MCI_IMAGE_PARMS));
   mciImageParms.hwndCallback = hwndNotify;
   mciImageParms.ulBufLen = 0;
   mciImageParms.pPelBuffer = 0;

   ulReturn = mciSendCommand(usDeviceID, MCI_GETIMAGEBUFFER,
                  MCI_WAIT | ulFlags,
                  (PVOID)&mciImageParms,
                  usUserParm);
   /*************************************/
   /* Allocate memory for the buffer    */
   /*************************************/
   DosAllocMem (&mciImageParms.pPelBuffer,
                mciImageParms.ulBufLen,
                PAG_COMMIT | PAG_WRITE);

   /*********************************/
   /* Get the data from the buffer  */
   /*********************************/
   ulReturn = mciSendCommand(usDeviceID, MCI_GETIMAGEBUFFER,
                  MCI_WAIT | ulFlags,
                  (PVOID)&mciImageParms,
                  usUserParm);

   pBMPhdr = (BITMAPINFOHEADER2 *)mciImageParms.pPelBuffer;

Note: The digital video device returns BITMAPFILEHEADER2 instead of BITMAPINFOHEADER2.

The following code illustrates how to capture an OS/2 bitmap from the hardware using the digital video device.

#define INCL_GPI
#define INCL_GPIBITMAPS

#include <os2.h>
#include <pmbitmap.h>

#define  INCL_MMIO
#define  INCL_MMIO_CODEC
#define  INCL_MMIO_DOSIOPROC
#include <os2me.h>
#include <stdlib.h>

/*****************************************************************
 * Name : BMPCaptureBitmap
 *
 * Function: Capture bitmap from hardware
 *
 ******************************************************************/
 VOID BMPCaptureBitmap(PSWVRCB pCB, HWND hwnd)
 {
   MCI_IMAGE_PARMS  mciImageParms;
   PCHAR            pBuf=0L;
   HFILE            hBMP;
   ULONG            ulAction;
   ULONG            cBytes;
   LONG             rc;

   memset ((PVOID)&mciImageParms, 0x00, sizeof (MCI_IMAGE_PARMS));

   /* prepare structures */
   mciImageParms.pPelBuffer   = 0L;
   mciImageParms.ulBufLen     = 0L;

   mciImageParms.rect.xLeft   = pCB->recopts[usIndex].usCapPosX;
   mciImageParms.rect.yBottom = pCB->recopts[usIndex].usCapPosY;
   mciImageParms.rect.xRight  = pCB->recopts[usIndex].usCapSizeX +
                                pCB->recopts[usIndex].usCapPosX;
   mciImageParms.rect.yTop    = pCB->recopts[usIndex]usCapSizeY +
                                pCB->recopts[usIndex].usCapPosY;
   mciImageParms.ulPelBufferWidth  = pCB->recopts[usIndex].usMovieSizeX;
   mciImageParms.ulPelBufferHeight = pCB->recopts[usIndex].usMovieSizeY;

   rc = mciSendCommand( pCB->OutputMovie.usDeviceID,
                        MCI_GETIMAGEBUFFER,
                        MCI_WAIT | MCI_USE_HW_BUFFER | MCI_CONVERT,
                        (ULONG)&mciImageParms,
                        0);

   rc = DosAllocMem ( (PPVOID) &pBuf,
                      (ULONG)   mciImageParms.ulBufLen,
                      (ULONG)   PAG_COMMIT | PAG_READ | PAG_WRITE);
                      mciImageParms.pPelBuffer=(PVOID)pBuf;

   rc = mciSendCommand( pCB->OutputMovie.usDeviceID,
                        MCI_GETIMAGEBUFFER,
                        MCI_WAIT | MCI_USE_HW_BUFFER | MCI_CONVERT,
                        (ULONG)&mciImageParms,
                        0);
   if (!rc)
    {
     /* getimage buffer is successful open file and write out bitmap */
     rc = DosOpen ( (PSZ)pCB->szBitmapFilename, &hBMP, &ulAction, 0, FILE_NORMAL,
                    FILE_CREATE,
                    OPEN_ACCESS_WRITEONLY | OPEN_SHARE_DENYWRITE,
                    0L);

     rc = DosWrite (hBMP, (PVOID)pBuf,
                    mciImageParms.ulBufLen,
                    &cBytes);

     rc = DosClose (hBMP);
    }

    /* free buffers */
     DosFreeMem( pBuf );

 }

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