EasyPlayerPro Windows播放器本地快照抓拍截图功能实现方法

背景描述

作为一个播放器，截图功能必不可少; 下面主要记录一下截图功能的实现；

实现流程

• 将解码后的帧进行格式转换(目标格式为RGB24);

• 采用独立的线程进行截图处理;

• 截图可保存为BMP或JPG两种格式;

代码实现

#define _WIDTHBYTES(c)  ((c+31)/32*4)   // c = width * bpp
int Snapshot2File(RENDER_FORMAT renderFormat, SNAPSHOT_IMAGE_T *pSnapshot, char *pbuf)
{
PBYTE   pDest = NULL, pDest16 = NULL;
INT     nBpp;
DWORD   dwW, dwH, dwWB;

int     ret = 0;

int image_format = pSnapshot->imageFormat;

if (renderFormat == RENDER_FORMAT_YUY2)             nBpp    =   16;
else if (renderFormat == RENDER_FORMAT_UYVY)        nBpp    =   16;
else if (renderFormat == RENDER_FORMAT_X8R8G8B8)    nBpp    =   32;     //ok
else if (renderFormat == RENDER_FORMAT_A8R8G8B8)    nBpp    =   32;     //ok
else if (renderFormat == RENDER_FORMAT_RGB565)      nBpp    =   16;     //ok
else if (renderFormat == RENDER_FORMAT_RGB555)      nBpp    =   16;     //ok
else if (renderFormat == RENDER_FORMAT_RGB24_GDI)   nBpp    =   24;
else    return -1;      //格式错误

dwW  = pSnapshot->width;
dwH  = pSnapshot->height;
dwWB = _WIDTHBYTES( dwW * nBpp );

if (image_format == 0x00)
{
    //BMP
    int iFilenameLen = (int)strlen(pSnapshot->filename);

    if ( (0 != memcmp(pSnapshot->filename+iFilenameLen-3, "bmp", 3)) &&
        (0 != memcmp(pSnapshot->filename+iFilenameLen-3, "BMP", 3)) &&
        (0 != memcmp(pSnapshot->filename+iFilenameLen-3, "Bmp", 3)) )
    {
        if (pSnapshot->filename[iFilenameLen-4] == '.')
        {
            for (int i=iFilenameLen-1; i>0; i--)
            {
                if (pSnapshot->filename[i] == '.')
                {
                    pSnapshot->filename[i] = '\0';
                    break;
                }
                else
                {
                    pSnapshot->filename[i] = '\0';
                }
            }
        }
        strcat(pSnapshot->filename, ".bmp");
    }

    HANDLE hFile = CreateFile( pSnapshot->filename, GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ | FILE_SHARE_WRITE,
        NULL,       CREATE_ALWAYS,  FILE_ATTRIBUTE_NORMAL,  NULL );
    if( hFile == INVALID_HANDLE_VALUE ) return E_HANDLE;

    // SaveFile to BMP
    BITMAPFILEHEADER bfh = {0};
    bfh.bfType      = 0x4D42;
    bfh.bfSize      = 0;
    bfh.bfReserved1 = 0;
    bfh.bfReserved2 = 0;
    bfh.bfOffBits = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER);
    if( nBpp == 16 ) {
        bfh.bfOffBits += sizeof(RGBQUAD) * 3;
    }
    else
        if( nBpp == 24 ) {
            bfh.bfOffBits += sizeof(RGBQUAD) * 1;
        }
        else
            if( nBpp == 32 ) {
                bfh.bfOffBits += sizeof(RGBQUAD) * 1;
            }
            DWORD dwWriteLength = sizeof(BITMAPFILEHEADER);
            DWORD dwWrittenLength = 0;
            WriteFile( hFile, (PVOID)&bfh, dwWriteLength, &dwWrittenLength, NULL );

            BITMAPINFOHEADER    bih = {0};
            bih.biSize      = sizeof(BITMAPINFOHEADER);
            bih.biWidth     = dwW;
            bih.biHeight    = -(INT)dwH;
            bih.biPlanes    = 1;
            bih.biBitCount  = nBpp;
            bih.biCompression   = (nBpp == 16) ? BI_BITFIELDS : BI_RGB;
            bih.biSizeImage     = dwWB * pSnapshot->height;
            bih.biXPelsPerMeter = 0;
            bih.biYPelsPerMeter = 0;
            bih.biClrUsed       = 0;
            bih.biClrImportant  = 0;

            dwWriteLength = sizeof(BITMAPINFOHEADER);
            WriteFile( hFile, (PVOID)&bih, dwWriteLength, &dwWrittenLength, NULL );

            if( nBpp == 16 ) {

                DWORD argbQuad[3] = {0};
                if (renderFormat == RENDER_FORMAT_RGB565)
                {
                    argbQuad[0] = 0x00F800;     // Red mask
                    argbQuad[1] = 0x0007E0;     // Green mask
                    argbQuad[2] = 0x00001F;     // Blue mask
                }
                else
                {
                    argbQuad[0] = 0x007C00;     // Red mask
                    argbQuad[1] = 0x0003E0;     // Green mask
                    argbQuad[2] = 0x00001F;     // Blue mask
                }
                dwWriteLength = sizeof(argbQuad);
                WriteFile( hFile, (PVOID)&argbQuad[0], dwWriteLength, &dwWrittenLength, NULL );
            }
            else
                if( nBpp == 24 ) {
                    DWORD rgbQuad = 0;
                    dwWriteLength = sizeof(rgbQuad);
                    WriteFile( hFile, (PVOID)&rgbQuad, dwWriteLength, &dwWrittenLength, NULL );
                }
                else if( nBpp == 32 ) {
                    DWORD rgbQuad = 0;
                    dwWriteLength = sizeof(rgbQuad);
                    WriteFile( hFile, (PVOID)&rgbQuad, dwWriteLength, &dwWrittenLength, NULL );
                }

                dwWriteLength = dwWB * pSnapshot->height;
                WriteFile( hFile, (PVOID)pbuf, dwWriteLength, &dwWrittenLength, NULL );
                CloseHandle( hFile );

    if (dwWrittenLength < 1)
    {
        DeleteFile(pSnapshot->filename);
    }
}
else if (image_format == 0x01)
{
    //JPG
    int iFilenameLen = (int)strlen(pSnapshot->filename);

    if ( (0 != memcmp(pSnapshot->filename+iFilenameLen-3, "jpg", 3)) &&
        (0 != memcmp(pSnapshot->filename+iFilenameLen-3, "JPG", 3)) &&
        (0 != memcmp(pSnapshot->filename+iFilenameLen-3, "Jpg", 3)) )
    {
        if (pSnapshot->filename[iFilenameLen-4] == '.')
        {
            for (int i=iFilenameLen-1; i>0; i--)
            {
                if (pSnapshot->filename[i] == '.')
                {
                    pSnapshot->filename[i] = '\0';
                    break;
                }
                else
                {
                    pSnapshot->filename[i] = '\0';
                }
            }
        }
        strcat(pSnapshot->filename, ".jpg");
    }

    BOOL bres = TRUE;
    IJLERR jerr;
    DWORD dibPadBytes;
    JPEG_CORE_PROPERTIES jcprops;

    __try
    {
        jerr = ijlInit(&jcprops);

        if (IJL_OK != jerr)
        {
            bres = FALSE;
            __leave;
        }

        dibPadBytes = IJL_DIB_PAD_BYTES(dwW, 3);

        jcprops.DIBWidth = dwW;
        jcprops.DIBHeight = dwH;
        jcprops.DIBBytes = (unsigned char*)pbuf;//reinterpret_cast<BYTE *>(&pbi->bmiHeader) + sizeof(BITMAPINFOHEADER);

        jcprops.DIBPadBytes = dibPadBytes;
        jcprops.DIBChannels = 3;
        jcprops.DIBColor = IJL_BGR;

        jcprops.JPGFile = const_cast<LPSTR>(pSnapshot->filename);

        jcprops.JPGWidth = dwW;
        jcprops.JPGHeight = dwH;

        jcprops.JPGChannels = 3;
        jcprops.JPGColor = IJL_YCBCR;
        jcprops.JPGSubsampling = IJL_411;
        jcprops.jquality = 95;

        jerr = ijlWrite(&jcprops, IJL_JFILE_WRITEWHOLEIMAGE);

        if (IJL_OK != jerr)
        {
            if (IJL_FILE_ERROR == jerr)
            {
            }
            ret = jerr;
            bres = FALSE;

            if (ret == -23)
            {
                DeleteFile(pSnapshot->filename);
            }
        }
    }

    __finally
    {
        ijlFree(&jcprops);
    }

}

if (NULL != pDest)
{
    delete []pDest;
    pDest = NULL;
}

return ret;
}

关于EasyPlayerPro

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