//-----------------------------------------------------------------------------
// CorrectAspectRatio
//
// Converts a rectangle from the source's pixel aspect ratio (PAR) to 1:1 PAR.
// Returns the corrected rectangle.
//
// For example, a 720 x 486 rect with a PAR of 9:10, when converted to 1x1 PAR,
// is stretched to 720 x 540.
//-----------------------------------------------------------------------------
private static Rectangle CorrectAspectRatio(Rectangle src, MFRatio srcPAR)
{
// Start with a rectangle the same size as src, but offset to the origin (0,0).
Rectangle rc = new Rectangle(0, 0, src.Right - src.Left, src.Bottom - src.Top);
int rcNewWidth = rc.Right;
int rcNewHeight = rc.Bottom;
if ((srcPAR.Numerator != 1) || (srcPAR.Denominator != 1))
{
// Correct for the source's PAR.
if (srcPAR.Numerator > srcPAR.Denominator)
{
// The source has "wide" pixels, so stretch the width.
rcNewWidth = Kernal32.MulDiv(rc.Right, srcPAR.Numerator, srcPAR.Denominator);
}
else if (srcPAR.Numerator < srcPAR.Denominator)
{
// The source has "tall" pixels, so stretch the height.
rcNewHeight = Kernal32.MulDiv(rc.Bottom, srcPAR.Denominator, srcPAR.Numerator);
}
// else: PAR is 1:1, which is a no-op.
}
rc = new Rectangle(0, 0, rcNewWidth, rcNewHeight);
return(rc);
}
public void SetFrameRate(MFRatio fps)
{
// Convert to a duration.
HResult hr = MFExtern.MFFrameRateToAverageTimePerFrame(fps.Numerator, fps.Denominator, out m_PerFrameInterval);
MFError.ThrowExceptionForHR(hr);
// Calculate 1/4th of this value, because we use it frequently.
m_PerFrame_1_4th = m_PerFrameInterval / 4;
}
//
// The following versions return reasonable defaults if the relevant attribute is not present (zero/FALSE).
// This is useful for making quick comparisons betweeen media types.
//
public MFRatio GetPixelAspectRatio() // Defaults to 1:1 (square pixels)
{
MFRatio PAR = new MFRatio();
try
{
Utils.MFGetAttribute2UINT32asUINT64(GetMediaType(), MFAttributesClsid.MF_MT_PIXEL_ASPECT_RATIO, out PAR.Numerator, out PAR.Denominator);
}
catch
{
PAR.Numerator = 1;
PAR.Denominator = 1;
}
return(PAR);
}
//-------------------------------------------------------------------
// SetVideoType
//
// Set the video format.
//-------------------------------------------------------------------
public HResult InitializeSetVideoSize(int width, int height, MFRatio ratio)
{
HResult hr = HResult.S_OK;
// Choose a conversion function.
// (This also validates the format type.)
hr = SetConversionFunction(MFMediaType.YUY2);
if (Failed(hr))
{
goto done;
}
// Get some video attributes.
m_width = width;
m_height = height;
m_PixelAR = ratio;
FourCC f = new FourCC(MFMediaType.YUY2);
m_format = (Format)f.ToInt32();
// Get the image stride.
hr = MFExtern.MFGetStrideForBitmapInfoHeader(f.ToInt32(), width, out m_lDefaultStride);
// Create Direct3D swap chains.
hr = CreateSwapChains();
if (Failed(hr))
{
goto done;
}
// Update the destination rectangle for the correct
// aspect ratio.
UpdateDestinationRect();
done:
if (Failed(hr))
{
m_format = Format.Unknown;
m_convertFn = null;
}
return(hr);
}
protected HRESULT CalculateOutputRectangle(IMFMediaType pProposedType, out DsRect prcOutput)
{
prcOutput = null;
HRESULT hr = S_OK;
int srcWidth = 0, srcHeight = 0;
MFRatio inputPAR = new MFRatio(0, 0);
MFRatio outputPAR = new MFRatio(0, 0);
DsRect rcOutput = new DsRect(0, 0, 0, 0);
MFVideoArea displayArea;
MFHelper.VideoTypeBuilder pmtProposed = null;
// Helper object to read the media type.
hr = MFHelper.MediaTypeBuilder.Create(pProposedType, out pmtProposed);
if (hr.Failed) return hr;
// Get the source's frame dimensions.
hr = pmtProposed.GetFrameDimensions(out srcWidth, out srcHeight);
if (hr.Failed) return hr;
// Get the source's display area.
hr = pmtProposed.GetVideoDisplayArea(out displayArea);
if (hr.Failed) return hr;
// Calculate the x,y offsets of the display area.
int offsetX = (int)displayArea.OffsetX.GetOffset();
int offsetY = (int)displayArea.OffsetY.GetOffset();
// Use the display area if valid. Otherwise, use the entire frame.
if (displayArea.Area.Width != 0 &&
displayArea.Area.Height != 0 &&
offsetX + displayArea.Area.Width <= (srcWidth) &&
offsetY + displayArea.Area.Height <= (srcHeight))
{
rcOutput.left = offsetX;
rcOutput.right = offsetX + displayArea.Area.Width;
rcOutput.top = offsetY;
rcOutput.bottom = offsetY + displayArea.Area.Height;
}
else
{
rcOutput.left = 0;
rcOutput.top = 0;
rcOutput.right = srcWidth;
rcOutput.bottom = srcHeight;
}
// rcOutput is now either a sub-rectangle of the video frame, or the entire frame.
// If the pixel aspect ratio of the proposed media type is different from the monitor's,
// letterbox the video. We stretch the image rather than shrink it.
inputPAR = pmtProposed.GetPixelAspectRatio(); // Defaults to 1:1
outputPAR.Denominator = outputPAR.Numerator = 1; // This is an assumption of the sample.
// Adjust to get the correct picture aspect ratio.
prcOutput = MFHelper.CorrectAspectRatio(rcOutput, inputPAR, outputPAR);
return NOERROR;
}
public void SetFrameRate(MFRatio fps)
{
long AvgTimePerFrame = 0;
// Convert to a duration.
MFFrameRateToAverageTimePerFrame(fps.Numerator, fps.Denominator, out AvgTimePerFrame);
m_PerFrameInterval = AvgTimePerFrame;
// Calculate 1/4th of this value, because we use it frequently.
m_PerFrame_1_4th = m_PerFrameInterval / 4;
}
protected HRESULT SetMediaType(IMFMediaType pMediaType)
{
// Note: pMediaType can be NULL (to clear the type)
// Clearing the media type is allowed in any state (including shutdown).
if (pMediaType == null)
{
m_pMediaType = null;
ReleaseResources();
return S_OK;
}
HRESULT hr = S_OK;
MFRatio fps = new MFRatio(0, 0);
// Cannot set the media type after shutdown.
hr = CheckShutdown();
if (hr.Succeeded)
{
// Check if the new type is actually different.
// Note: This function safely handles NULL input parameters.
if (MFHelper.AreMediaTypesEqual(m_pMediaType, pMediaType))
{
return S_OK; // Nothing more to do.
}
// We're really changing the type. First get rid of the old type.
m_pMediaType = null;
ReleaseResources();
// Initialize the presenter engine with the new media type.
// The presenter engine allocates the samples.
hr = CreateVideoSamples(pMediaType);
if (hr.Succeeded)
{
// Set the frame rate on the scheduler.
if (SUCCEEDED(MFHelper.GetFrameRate(pMediaType, out fps)) && (fps.Numerator != 0) && (fps.Denominator != 0))
{
m_scheduler.SetFrameRate(fps);
}
else
{
// NOTE: The mixer's proposed type might not have a frame rate, in which case
// we'll use an arbitary default. (Although it's unlikely the video source
// does not have a frame rate.)
m_scheduler.SetFrameRate(g_DefaultFrameRate);
}
// Store the media type.
ASSERT(pMediaType != NULL);
m_pMediaType = pMediaType;
}
}
if (hr.Failed)
{
ReleaseResources();
}
return hr;
}
public HResult SetVideoType(IMFMediaType pType)
{
HResult hr = HResult.S_OK;
Guid subtype;
MFRatio PAR = new MFRatio();
// Find the video subtype.
hr = pType.GetGUID(MFAttributesClsid.MF_MT_SUBTYPE, out subtype);
if (Failed(hr))
{
goto done;
}
// Choose a conversion function.
// (This also validates the format type.)
hr = SetConversionFunction(subtype);
if (Failed(hr))
{
goto done;
}
//
// Get some video attributes.
//
// Get the frame size.
hr = MFExtern.MFGetAttributeSize(pType, MFAttributesClsid.MF_MT_FRAME_SIZE, out m_width, out m_height);
if (Failed(hr))
{
goto done;
}
// Get the image stride.
hr = GetDefaultStride(pType, out m_lDefaultStride);
if (Failed(hr))
{
goto done;
}
// Get the pixel aspect ratio. Default: Assume square pixels (1:1)
hr = MFExtern.MFGetAttributeRatio(pType, MFAttributesClsid.MF_MT_PIXEL_ASPECT_RATIO, out PAR.Numerator, out PAR.Denominator);
if (Succeeded(hr))
{
m_PixelAR = PAR;
}
else
{
m_PixelAR.Numerator = m_PixelAR.Denominator = 1;
}
FourCC f = new FourCC(subtype);
m_format = (Format)f.ToInt32();
// Create Direct3D swap chains.
hr = CreateSwapChains();
if (Failed(hr))
{
goto done;
}
// Update the destination rectangle for the correct
// aspect ratio.
UpdateDestinationRect();
done:
if (Failed(hr))
{
m_format = Format.Unknown;
m_convertFn = null;
}
return(hr);
}
public void SetPixelAspectRatio(MFRatio ratio)
{
Utils.MFSetAttribute2UINT32asUINT64(GetMediaType(), MFAttributesClsid.MF_MT_PIXEL_ASPECT_RATIO, ratio.Numerator, ratio.Denominator);
}
// Sets the number of frames per second, as a ratio.
public void SetFrameRate(MFRatio ratio)
{
Utils.MFSetAttribute2UINT32asUINT64(GetMediaType(), MFAttributesClsid.MF_MT_FRAME_RATE, ratio.Numerator, ratio.Denominator);
}
// Gets the frames per second as a ratio.
public void GetFrameRate(out MFRatio pRatio)
{
GetFrameRate(out pRatio.Numerator, out pRatio.Denominator);
}
//-------------------------------------------------------------------
// SetVideoType
//
// Set the video snapFormat.
//-------------------------------------------------------------------
public int SetVideoType(IMFMediaType pType)
{
Guid subtype;
var PAR = new MFRatio();
// Find the video subtype.
var hr = pType.GetGUID(MFAttributesClsid.MF_MT_SUBTYPE, out subtype);
try
{
if (Failed(hr))
{
throw new Exception();
}
// Choose a conversion function.
// (This also validates the snapFormat type.)
hr = SetConversionFunction(subtype);
if (Failed(hr))
{
throw new Exception();
}
//
// Get some video attributes.
//
// Get the frame size.
hr = CProcess.MfGetAttributeSize(pType, out width, out height);
if (Failed(hr))
{
throw new Exception();
}
// Get the image stride.
hr = GetDefaultStride(pType, out lDefaultStride);
if (Failed(hr))
{
throw new Exception();
}
// Get the pixel aspect ratio. Default: Assume square pixels (1:1)
hr = CProcess.MfGetAttributeRatio(pType, out PAR.Numerator, out PAR.Denominator);
if (Succeeded(hr))
{
pixelAR = PAR;
}
else
{
pixelAR.Numerator = pixelAR.Denominator = 1;
}
var f = new FourCC(subtype);
format = (Format)f.ToInt32();
// Create Direct3D swap chains.
hr = CreateSwapChains();
if (Failed(hr))
{
throw new Exception();
}
// Update the destination rectangle for the correct
// aspect ratio.
UpdateDestinationRect();
}
finally
{
if (Failed(hr))
{
format = Format.Unknown;
m_convertFn = null;
}
}
return(hr);
}
