formatdata.cpp

完整的基于Conxant平台的USB电视棒的WIN驱动程序。

/*+++ *******************************************************************\ 
* 
*  Copyright and Disclaimer: 
*  
*     --------------------------------------------------------------- 
*     This software is provided "AS IS" without warranty of any kind, 
*     either expressed or implied, including but not limited to the 
*     implied warranties of noninfringement, merchantability and/or 
*     fitness for a particular purpose.
*     --------------------------------------------------------------- 
*   
*     Copyright (c) 2008 Conexant Systems, Inc. 
*     All rights reserved. 
*
\******************************************************************* ---*/ 

#include "FormatData.h"
#include "debug.h"

#define FCC_VBI     0xf72a76e0L 


FormatData::
FormatData():
    _image_height( 0 ),   
    _image_width( 0 ),    
    _stride_in_bytes( 0 ),
    _bit_count( 0 ),      
    _compression( 0 )    
{
}


FormatData::
FormatData( 
    const KS_VIDEOINFOHEADER  *p_info 
    )
{
    _image_height = p_info->bmiHeader.biHeight;   
    _image_width  = p_info->bmiHeader.biWidth;
    _bit_count    = p_info->bmiHeader.biBitCount;      
    _compression  = p_info->bmiHeader.biCompression;

    /****************************************************************
    *
    *   This is a little tricky to handle DirectDraw stride issues.
    *   The rule from the DDK docs is as follows...
    *
    *   Special rules apply when the output buffer is a
    *   DirectDraw surface. In this case, the biWidth
    *   member of the BITMAPINFOHEADER structure actually
    *   represents the 'stride' of the destination
    *   DirectDraw surface, which will typically be
    *   larger than the video image width. Therefore,
    *   to determine the requested image width, the
    *   following pseudocode should be used:
    *
    *   if (IsRectEmpty(&pVideoInfoHdrRequested->rcTarget) {
    *       Width =  pVideoInfoHdrRequested->bmiHeader.biWidth;
    *       Height = pVideoInfoHdrRequested->bmiHeader.biHeight;
    *   }
    *   else {
    *       Width = pVideoInfoHdrRequested->rcTarget.right -
    *               pVideoInfoHdrRequested->rcTarget.left;
    *       Height = pVideoInfoHdrRequested->rcTarget.bottom -
    *                pVideoInfoHdrRequested->rcTarget.top;
    *   }
    *
    *   Note: It seems like the stride that gets stuffed into
    *         pVideoInfoHdrRequested->bmiHeader.biWidth is the
    *         stride in *pixels*, not bytes.
    *
    *****************************************************************/
    _stride_in_bytes = p_info->bmiHeader.biWidth * _bit_count / 8;
    _stride_in_bytes = ( _stride_in_bytes + 3 ) & ~3;

    if( p_info->rcTarget.right > p_info->rcTarget.left )
        _image_width = p_info->rcTarget.right - p_info->rcTarget.left;
}


FormatData::
FormatData( 
    const KS_VBIINFOHEADER *p_info 
    )
{
    // Since Endline and StartLine are inclusive add 1
    _image_height    = p_info->EndLine - p_info->StartLine + 1;   
    _image_width     = p_info->StrideInBytes;    
    _stride_in_bytes = p_info->StrideInBytes;
    _bit_count       = 8;      
    _compression     = FCC_VBI;    
}