• Blackmagic Design

  BlueScreen when using bmdVideoOutputDualStream3D

  Posted by Erwin Kloibhofer on January 31, 2012 at 2:32 am

  For the last couple of days I am struggling to find the cause of the following problem: a very minimal DirectX9 based Windows test application stops receiving ScheduledFrameCompleted() after a period anywhere between 5 and 60 minutes, but the app keeps on running anyway. Then when I try to exit the application it gets stuck inside DisableVideoOutput(). The only thing left at this point is to kill the process via the TaskManager, which then results in a BlueScreen (PROCESS_HAS_LOCKED_PAGES in “ntoskrnl.exe”).

  I have two Windows Pro 7 machines (64 bit) available with a Decklink HD Extreme 3D plugged in each of them. The hardware setup is relatively similar, both use a Radeon HD 5770, although my workstation here has a Core-i5 processor, and the second machine (btw 1000 km away from here), is Xeon based. I am using the same Radeon drivers (12.1), and Decklink drivers (9.0).

  This issue only occurs on the remote machine, not on my local workstation here. I only have these 2 machines available, if I had a third one I could probably tell if this is a hardware problem, a driver issue or a problem with my code.

  Now for the code: I am using bmdVideoOutputDualStream3D to output a fill and key stream on the Decklink Extreme – so I basically “mis-use” the 3D feature. Although Blackmagic support recommended to do it this way, since that’s the only way to get in-sync fill and key streams.

  First thing I noticed when programming, was that the ordinary IDeckLinkMutableVideoFrame class can not be used when using the bmdVideoOutputDualStream3D flag. So I put together the “DeckLink3dVideoFrame” class, based on code fragments I found on the Blackmagic mailing list.

  My test code is very simple, basically it does this:

  
BeginScene
Clear
// no rendering what so ever happens
EndScene
Present
GetRenderTargetData
StoreFrameBufferForLaterUse


  When ScheduledFrameCompleted() is called I memcpy the previously stored frame into the frame buffer of the left eye, and at the same time copy the alpha-channel into the right eye frame-buffer, using the CPU.

  This all works perfectly on my work-station here, and only shows that malfunction on the remote machine. There are two methods to avoid the malfunction:

  1) Use bmdVideoOutputFlagDefault instead of bmdVideoOutputDualStream3D when calling EnableVideoOutput() (but still keep on using the DeckLink3dVideoFrame class)
  2) Comment out the call to IDirect3DDevice9::GetRenderTargetData()

  In case of 1) this could point to a problem inside DeckLink3dVideoFrame class, which as I mentioned is based on code-fragements. Could someone have a look at it? Of course this could also be caused by a driver error, or a hardware problem.

  I think I picked up somewhere that bmdVideoOutputDualStream3D only works with YUV? However I passed bmdFormat8BitBGRA as the screen-format when creating the buffer, and this works flawlessly on my machine here.

  I would really appreciate any pointers, because I am sort of running out of ideas…

  Here’s the code for DeckLink3dVideoFrame:

  
// -----------------------------------------------------------------------------
class DecklinkOutput::DeckLink3dVideoFrame : public IDeckLinkVideoFrame, public IDeckLinkVideoFrame3DExtensions
// -----------------------------------------------------------------------------
{
public:
DeckLink3dVideoFrame() : mRightEyeFrame(0), mWidth(0), mHeight(0), mPitch(0), mBuffer(0), mRefCount(1) {}
virtual ~DeckLink3dVideoFrame() { delete mBuffer; }

  bool CreateVideoFrame(int w, int h, int pitch, BMDPixelFormat pixelFormat)
  {
  mWidth = w;
  mHeight = h;
  mPitch = pitch;
  mPixelFormat = pixelFormat;

  mBuffer = new BYTE[mPitch * mHeight];
  return true;
  }

  long STDMETHODCALLTYPE GetWidth() { return mWidth; }
  long STDMETHODCALLTYPE GetHeight() { return mHeight; }
  long STDMETHODCALLTYPE GetRowBytes() { return mPitch; }
  BMDPixelFormat STDMETHODCALLTYPE GetPixelFormat() { return mPixelFormat; }
  BMDFrameFlags STDMETHODCALLTYPE GetFlags() { return 0; }

  HRESULT STDMETHODCALLTYPE GetBytes(void** buffer)
  {
  *buffer = mBuffer;
  return S_OK;
  }

  void SetRightEyeFrame(DeckLink3dVideoFrame* right) { mRightEyeFrame = right; }

  HRESULT STDMETHODCALLTYPE GetTimecode(BMDTimecodeFormat format, IDeckLinkTimecode **timecode) { return E_FAIL; }
  HRESULT STDMETHODCALLTYPE GetAncillaryData(IDeckLinkVideoFrameAncillary **ancillary) { return E_FAIL; }

  HRESULT STDMETHODCALLTYPE QueryInterface(REFIID iid, LPVOID* ppv)
  {
  HRESULT result = E_NOINTERFACE;

  // initialize the return result
  *ppv = NULL;

  // obtain the IUnknown interface and compare it the provided REFIID
  if (iid == IID_IUnknown)
  {
  *ppv = this;
  AddRef();
  result = S_OK;
  }
  else if (iid == IID_IDeckLinkVideoFrame3DExtensions)
  {
  *ppv = (IDeckLinkVideoFrame3DExtensions*)this;
  AddRef();
  result = S_OK;
  }

  return result;
  }

  ULONG STDMETHODCALLTYPE AddRef()
  {
  return InterlockedIncrement((LONG*)&mRefCount);
  }

  ULONG STDMETHODCALLTYPE Release()
  {
  int newRefValue = InterlockedDecrement((LONG*)&mRefCount);

  if (newRefValue == 0)
  {
  delete this;
  return 0;
  }

  return newRefValue;
  }

  BMDVideo3DPackingFormat STDMETHODCALLTYPE Get3DPackingFormat()
  {
  if (mRightEyeFrame)
  return bmdVideo3DPackingLeftOnly;
  else
  return bmdVideo3DPackingRightOnly;
  }

  HRESULT STDMETHODCALLTYPE GetFrameForRightEye(IDeckLinkVideoFrame** rightEyeFrame)
  {
  *rightEyeFrame = mRightEyeFrame;

  if (mRightEyeFrame)
  {
  mRightEyeFrame->AddRef();
  return S_OK;
  }
  else
  {
  return S_FALSE;
  }
  }

  private:
  int mRefCount;
  DeckLink3dVideoFrame* mRightEyeFrame;

  int mWidth;
  int mHeight;
  int mPitch;
  BMDPixelFormat mPixelFormat;
  BYTE* mBuffer;
  };

  Erwin Kloibhofer replied 14 years, 8 months ago 1 Member · 0 Replies
• 0 Replies

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