在我之前写的一篇文章《SkeyeRTSPLive传统视频监控互联网 实现利器解决方案》中提到RTSP转RTMP的转流过程，简化流程就是通过SkeyeRTSPClient拉RTSP流，获取音视频编码数据，然后再通过SkeyeRTMPPusher推出去，流程非常简单；然后再实际开发过程中，我们发现其实这个过程并没有想象中那么简单；首先，RTSP协议支持多种音视频编码格式，如音频支持AAC,G711，G726,等，视频支持H264，H625，MJPEG, MPEG等等各种格式，而SkeyeRTMP推流只支持H264（已扩展支持H265）格式，这时，音频我们可以通过SkeyeAACEncoder将音频转码成AAC格式，而视频我们可以通过SkeyeVideoDecoder解码成原始数据，然后再通过SkeyeVideoEncoder将原始数据转码成RTMP推送指定的格式，本文，我们将重点讲述SkeyeVideoDecoder基于Intel硬解码库的硬解码流程。
SkeyeVideoDecoder基于Intel硬解码库SkeyeIntelHardDecoder
SkeyeIntelHardDecoder库是基于Intel主板集成显卡的硬件解码程序，内部进行解码采用D3D进行显示，其解码效率比ffmpeg软件解码效率提到至少5-6倍；
1. 接口声明如下：
代码语言：txt复制// Intel Media Hardware Codec SDK Interface [8/17/2016 SwordTwelve]
#ifndef INTELHARDCODEC_INTERFACE_H
#define INTELHARDCODEC_INTERFACE_H
#ifdef __cplusplus
#define HARDCODEC_MAKEFOURCC(A,B,C,D) ((((int)A)) (((int)B)<<8) (((int)C)<<16) (((int)D)<<24))
/* Hardware Codec FourCC */
typedef enum tagINTELHARDCODEC_FORMAT{
HARDCODEC_FOURCC_NV12 = HARDCODEC_MAKEFOURCC('N','V','1','2'), /* Native Format */
HARDCODEC_FOURCC_YV12 = HARDCODEC_MAKEFOURCC('Y','V','1','2'),
HARDCODEC_FOURCC_YUY2 = HARDCODEC_MAKEFOURCC('Y','U','Y','2'),
HARDCODEC_FOURCC_RGB3 = HARDCODEC_MAKEFOURCC('R','G','B','3'), /* RGB24 */
HARDCODEC_FOURCC_RGB4 = HARDCODEC_MAKEFOURCC('R','G','B','4'), /* RGB32 */
HARDCODEC_FOURCC_P8 = 41, /* D3DFMT_P8 */
HARDCODEC_FOURCC_P8_TEXTURE = HARDCODEC_MAKEFOURCC('P','8','M','B')
}INTELHARDCODEC_FORMAT;
class SkeyeIntelHardDecoder_Interface
{
//导出接口
public:
public: //DLL 接口
virtual int WINAPI Init(HWND hWnd, bool bDxv2Show, bool bShowToScale, int mode = 1) = 0;
virtual int WINAPI Decode(unsigned char * pData, int len, OUT INTELHARDCODEC_FORMAT& outFormat, OUT unsigned char * pYUVData) = 0;
virtual void WINAPI Close() = 0;
};
//视频获取定义接口指针类型
typedef SkeyeIntelHardDecoder_Interface* LPIntelHardDecoder;
LPIntelHardDecoder APIENTRY Create_SkeyeIntelHardDecoder();//创建控制接口指针
void APIENTRY Release_SkeyeIntelHardDecoder(LPIntelHardDecoder lpHardDecoder);//销毁控制接口指针
#endif//__cplusplus
#endif//INTELHARDCODEC_INTERFACE_H2. SkeyeIntelHardDecoder解码库调用流程
- 第一步，初始化解码器 首先，检查设备是否支持DXVA2，代码如下所示：
bool sSupportDxva2(HWND hwnd)
{
HRESULT hr;
mfxU32 adapterNum = 0;
IDirect3D9* m_pD3D9 = NULL;
IDirect3DDevice9* m_pD3DD9 = NULL;
IDirect3DDeviceManager9* m_pDeviceManager9 = NULL;
D3DPRESENT_PARAMETERS m_D3DPP;
m_pD3D9 = Direct3DCreate9(D3D_SDK_VERSION);
if (!m_pD3D9)
return false;
ZeroMemory(&m_D3DPP, sizeof(m_D3DPP));
m_D3DPP.Windowed = true;
m_D3DPP.hDeviceWindow = hwnd;
m_D3DPP.Flags = D3DPRESENTFLAG_VIDEO;
m_D3DPP.FullScreen_RefreshRateInHz = D3DPRESENT_RATE_DEFAULT;
m_D3DPP.PresentationInterval = D3DPRESENT_INTERVAL_ONE;
m_D3DPP.BackBufferCount = 1;
m_D3DPP.BackBufferFormat = D3DFMT_X8R8G8B8;
m_D3DPP.BackBufferWidth = GetSystemMetrics(SM_CXSCREEN);
m_D3DPP.BackBufferHeight = GetSystemMetrics(SM_CYSCREEN);
m_D3DPP.Flags |= D3DPRESENTFLAG_LOCKABLE_BACKBUFFER;
m_D3DPP.SwapEffect = D3DSWAPEFFECT_DISCARD; // D3DSWAPEFFECT_OVERLAY
hr = m_pD3D9->CreateDevice(
adapterNum,
D3DDEVTYPE_HAL,
hwnd,
D3DCREATE_SOFTWARE_VERTEXPROCESSING | D3DCREATE_MULTITHREADED | D3DCREATE_FPU_PRESERVE,
&m_D3DPP,
&m_pD3DD9);
if (FAILED(hr))
{
m_pD3D9->Release();
return false;
}
hr = m_pD3DD9->Reset(&m_D3DPP);
if (FAILED(hr))
return false;
hr = m_pD3DD9->Clear(0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(0, 0, 0), 1.0f, 0);
if (FAILED(hr))
{
m_pD3DD9->Release();
m_pD3D9->Release();
return false;
}
UINT resetToken = 0;
hr = DXVA2CreateDirect3DDeviceManager9(&resetToken, &m_pDeviceManager9);
if (FAILED(hr))
{
m_pD3DD9->Release();
m_pD3D9->Release();
return false;
}
m_pDeviceManager9->Release();
m_pD3DD9->Release();
m_pD3D9->Release();
return true;
}然后，初始化解码器，代码如下：
代码语言：txt复制int Init(HWND hWnd, bool bDxv2Show, bool bShowToScale, int mode )
{
//检测是否支持硬件解码
bool bUseIntelSdk = isSupportDxva2(hWnd);
if (!bUseIntelSdk)
{
return -1;
}
m_bDxv2Show = bDxv2Show;
m_bShowToScale = bShowToScale;
m_hWnd = hWnd;
::GetClientRect(m_hWnd,&m_WndRect);
m_pD3dRender = new CDecodeD3DRender();
m_pD3dRender->Init(hWnd);
mfxStatus sts = MFX_ERR_NONE;
// mfxVersion version = {MFX_VERSION_MINOR, MFX_VERSION_MAJOR};
mfxVersion version = {0, 1};
if (mode == 1)
{
if (MFX_ERR_NONE != m_mfxSession.Init(MFX_IMPL_HARDWARE_ANY, &version))
sts = m_mfxSession.Init(MFX_IMPL_HARDWARE, &version);
if(sts != MFX_ERR_NONE)
sts = m_mfxSession.Init(MFX_IMPL_SOFTWARE, &version);
}
else
{
sts = m_mfxSession.Init(MFX_IMPL_SOFTWARE, &version);
}
MSDK_CHECK_RESULT(sts, MFX_ERR_NONE, sts);
// create decoder
m_pmfxDEC = new MFXVideoDECODE(m_mfxSession);
MSDK_CHECK_POINTER(m_pmfxDEC, MFX_ERR_MEMORY_ALLOC);
// set video type in parameters
m_mfxVideoParams.mfx.CodecId = MFX_CODEC_AVC;
m_mfxVideoParams.AsyncDepth = 1;
// [12/6/2016 dingshuai]
m_mfxVideoParams.mfx.FrameInfo.FourCC = MFX_FOURCC_NV12;//MFX_FOURCC_YV12;
// set memory type
m_bd3dAlloc = true;
memset(&m_mfxBS, 0, sizeof(m_mfxBS));
sts = InitMfxBitstream(&m_mfxBS, 1024*1024*2);
return sts;
}- 第二步，调用解码函数 解码器是异步工作的，所以在解码函数调用后，我们需要从缓冲区内把数据取出进行D3D显示或者回调到上层显示，代码如下所示：
mfxStatus CIntelMediaDecode::h264DecPacket(unsigned char * p_data, int len, unsigned char* p_yuvData)
{
mfxSyncPoint syncp;
mfxStatus sts = MFX_ERR_NONE;
mfxU16 nIndex = 0; // index of free surface
//while (MFX_ERR_NONE <= sts || MFX_ERR_MORE_DATA == sts || MFX_ERR_MORE_SURFACE == sts)
{
if (MFX_WRN_DEVICE_BUSY == sts)
{
MSDK_SLEEP(1); // just wait and then repeat the same call to DecodeFrameAsync
}
if (len > (m_mfxBS.MaxLength - m_mfxBS.DataLength))
{
// sts = ExtendMfxBitstream(&m_mfxBS, m_mfxBS.MaxLength * 2);
// MSDK_CHECK_RESULT(sts, MFX_ERR_NONE, sts);
m_mfxBS.DataOffset = 0;
m_mfxBS.DataLength = 0;
}
if (len > 0)
{
memmove(m_mfxBS.Data, m_mfxBS.Data m_mfxBS.DataOffset, m_mfxBS.DataLength);
m_mfxBS.DataOffset = 0;
memcpy(m_mfxBS.Data m_mfxBS.DataLength, p_data, len);
m_mfxBS.DataLength = len;
}
if (m_mfxBS.DataLength < 5)
{
m_sPrevState = MFX_ERR_MORE_DATA;
return MFX_ERR_MORE_DATA;
}
if (MFX_ERR_MORE_SURFACE == m_sPrevState || MFX_ERR_NONE == m_sPrevState)
{
nIndex = GetFreeSurfaceIndex(m_pmfxSurfaces, m_mfxResponse.NumFrameActual); // find new working surface
if (MSDK_INVALID_SURF_IDX == nIndex)
{
return MFX_ERR_MEMORY_ALLOC;
}
}
sts = m_pmfxDEC->DecodeFrameAsync(&m_mfxBS, &(m_pmfxSurfaces[nIndex]), &m_pmfxOutSurface, &syncp);
if (MFX_ERR_DEVICE_LOST == sts || MFX_ERR_DEVICE_FAILED == sts)
return sts;
m_sPrevState = sts;
// ignore warnings if output is available,
// if no output and no action required just repeat the same call
if (MFX_ERR_NONE < sts && syncp)
{
sts = MFX_ERR_NONE;
}
if (MFX_ERR_NONE == sts)
{
sts = m_mfxSession.SyncOperation(syncp, MSDK_DEC_WAIT_INTERVAL);
}
if (MFX_ERR_NONE == sts)
{
#if 0
if (m_nSnapShotRequest == 1)
{
picture->linesize[0] = m_pmfxOutSurface->Data.Pitch;
picture->linesize[1] = m_pmfxOutSurface->Data.Pitch;
picture->linesize[2] = 0;
picture->data[0] = m_pmfxOutSurface->Data.Y;
picture->data[1] = m_pmfxOutSurface->Data.UV;
picture->data[2] = 0;
int ret = SetSnapFrameData(picture);
if (ret > 0)
{
m_nSnapShotDataReady = 1;
}
m_nSnapShotRequest = 0;
}
#endif
#if 1
if (m_bExternalAlloc)
{
sts = m_pMFXAllocator->Lock(m_pMFXAllocator->pthis, m_pmfxOutSurface->Data.MemId, &(m_pmfxOutSurface->Data));
MSDK_CHECK_RESULT(sts, MFX_ERR_NONE, sts);
}
#endif
m_nFrameIndex;
int nYUVSize = m_nSrcWidth*m_nSrcHeight;
//YUV数据拷贝
if (p_yuvData)//YUV420
{
memcpy(p_yuvData, m_pmfxOutSurface->Data.Y, nYUVSize);
memcpy(p_yuvData m_nSrcWidth*m_nSrcHeight, m_pmfxOutSurface->Data.UV, m_nSrcWidth*m_nSrcHeight>>1);
// 硬件编码出来是NV12，外部为了显示方便应该转成I420 [12/6/2016 dingshuai]
#if 0
int i = 0;
int yuvDely = nYUVSize*5/4;
int nHelfYUVSize = nYUVSize/2;
// Write Cb
for(int idx = 0; idx < (nHelfYUVSize); idx =2)
{
*(p_yuvData nYUVSize i) = m_pmfxOutSurface->Data.UV[idx];
*(p_yuvData yuvDely i) = m_pmfxOutSurface->Data.UV[idx 1];
i ;
}
#endif
}
#if 1
if (m_bExternalAlloc)
{
sts = m_pMFXAllocator->Unlock(m_pMFXAllocator->pthis, m_pmfxOutSurface->Data.MemId, &(m_pmfxOutSurface->Data));
MSDK_CHECK_RESULT(sts, MFX_ERR_NONE, sts);
}
#endif
if (m_bDxv2Show)
{
::GetClientRect(m_hWnd, &m_WndRect);
sts = m_pD3dRender->RenderFrame(m_pmfxOutSurface, m_pMFXAllocator,
m_WndRect, m_DisplayTitle, m_bEndedDrag, m_bShowToScale, &m_TargetRect);
if (sts == MFX_ERR_NULL_PTR)
sts = MFX_ERR_NONE;
}
}
}
return sts;
}- 第三步，关闭解码器
void Close()
{
WipeMfxBitstream(&m_mfxBS);
MSDK_SAFE_DELETE(m_pmfxDEC);
MSDK_SAFE_DELETE(m_pD3dRender);
if (m_bIntelSystemInitFinish != true)
return;
m_bIntelSystemInitFinish = false;
DeleteFrames();
// allocator if used as external for MediaSDK must be deleted after decoder
DeleteAllocator();
m_mfxSession.Close();
if (NULL != m_pSnapShotBuf)
{
free(m_pSnapShotBuf);
m_pSnapShotBuf = NULL;
}
}至此，我们已经完成了对Intel集显解码器的封装，通过阅读SkeyeRTSPPlayer的代码可以对该库的调用流程有一个系统的认识；此外，目前集成的Intel集显解码库是比较旧的版本，目前尚不支持H265解码，有兴趣的朋友可以下载最新的Intel集显编解码库Demo自行封装解码库，相信现在的版本会更加的易用和高效。
