RENBASE.H

//==========================================================================; 
//
// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY
// KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR
// PURPOSE.
//
// Copyright (c) 1992 - 1997 Microsoft Corporation. All Rights Reserved.
//
//--------------------------------------------------------------------------;

// Generic ActiveX base renderer class, December 1995

#ifndef __RENBASE__
#define __RENBASE__

// Forward class declarations

class CBaseRenderer;
class CBaseVideoRenderer;
class CRendererInputPin;

// This is our input pin class that channels calls to the renderer

class CRendererInputPin : public CBaseInputPin
{
protected:

CBaseRenderer *m_pRenderer;

public:

CRendererInputPin(CBaseRenderer *pRenderer,
HRESULT *phr,
LPCWSTR Name);

// Overriden from the base pin classes

HRESULT BreakConnect();
HRESULT CompleteConnect(IPin *pReceivePin);
HRESULT SetMediaType(const CMediaType *pmt);
HRESULT CheckMediaType(const CMediaType *pmt);
HRESULT Active();
HRESULT Inactive();

// Add rendering behaviour to interface functions

STDMETHODIMP QueryId(LPWSTR *Id);
STDMETHODIMP EndOfStream();
STDMETHODIMP BeginFlush();
STDMETHODIMP EndFlush();
STDMETHODIMP Receive(IMediaSample *pMediaSample);

// Helper
IMemAllocator inline *Allocator() const
{
return m_pAllocator;
}
};

// Main renderer class that handles synchronisation and state changes

class CBaseRenderer : public CBaseFilter
{
protected:

friend class CRendererInputPin;

friend void CALLBACK EndOfStreamTimer(UINT uID, // Timer identifier
UINT uMsg, // Not currently used
DWORD dwUser, // User information
DWORD dw1, // Windows reserved
DWORD dw2); // Is also reserved

CRendererPosPassThru *m_pPosition; // Media seeking pass by object
CAMEvent m_RenderEvent; // Used to signal timer events
CAMEvent m_ThreadSignal; // Signalled to release worker thread
CAMEvent m_evComplete; // Signalled when state complete
BOOL m_bAbort; // Stop us from rendering more data
BOOL m_bStreaming; // Are we currently streaming
DWORD m_dwAdvise; // Timer advise cookie
IMediaSample *m_pMediaSample; // Current image media sample
BOOL m_bEOS; // Any more samples in the stream
BOOL m_bEOSDelivered; // Have we delivered an EC_COMPLETE
CRendererInputPin *m_pInputPin; // Our renderer input pin object
CCritSec m_InterfaceLock; // Critical section for interfaces
CCritSec m_RendererLock; // Controls access to internals
IQualityControl * m_pQSink; // QualityControl sink
BOOL m_bRepaintStatus; // Can we signal an EC_REPAINT
// Avoid some deadlocks by tracking filter during stop
volatile BOOL m_bInReceive; // Inside Receive between PrepareReceive
// And actually processing the sample
REFERENCE_TIME m_SignalTime; // Time when we signal EC_COMPLETE
UINT m_EndOfStreamTimer; // Used to signal end of stream

public:

CBaseRenderer(REFCLSID RenderClass, // CLSID for this renderer
TCHAR *pName, // Debug ONLY description
LPUNKNOWN pUnk, // Aggregated owner object
HRESULT *phr); // General OLE return code

~CBaseRenderer();

// Overriden to say what interfaces we support and where

virtual HRESULT GetMediaPositionInterface(REFIID riid,void **ppv);
STDMETHODIMP NonDelegatingQueryInterface(REFIID, void **);

virtual HRESULT SourceThreadCanWait(BOOL bCanWait);

#ifdef DEBUG
// Debug only dump of the renderer state
void DisplayRendererState();
#endif
virtual HRESULT WaitForRenderTime();
virtual HRESULT CompleteStateChange(FILTER_STATE OldState);

// Return internal information about this filter

BOOL IsEndOfStream() { return m_bEOS; };
BOOL IsEndOfStreamDelivered() { return m_bEOSDelivered; };
BOOL IsStreaming() { return m_bStreaming; };
void SetAbortSignal(BOOL bAbort) { m_bAbort = bAbort; };
virtual void OnReceiveFirstSample(IMediaSample *pMediaSample) { };
CAMEvent *GetRenderEvent() { return &m_RenderEvent; };

// Permit access to the transition state

void Ready() { m_evComplete.Set(); };
void NotReady() { m_evComplete.Reset(); };
BOOL CheckReady() { return m_evComplete.Check(); };

virtual int GetPinCount();
virtual CBasePin *GetPin(int n);
FILTER_STATE GetRealState();
void SendRepaint();
void SendNotifyWindow(IPin *pPin,HWND hwnd);
BOOL OnDisplayChange();
void SetRepaintStatus(BOOL bRepaint);

// Override the filter and pin interface functions

STDMETHODIMP Stop();
STDMETHODIMP Pause();
STDMETHODIMP Run(REFERENCE_TIME StartTime);
STDMETHODIMP GetState(DWORD dwMSecs,FILTER_STATE *State);
STDMETHODIMP FindPin(LPCWSTR Id, IPin **ppPin);

// These are available for a quality management implementation

virtual void OnRenderStart(IMediaSample *pMediaSample);
virtual void OnRenderEnd(IMediaSample *pMediaSample);
virtual HRESULT OnStartStreaming() { return NOERROR; };
virtual HRESULT OnStopStreaming() { return NOERROR; };
virtual void OnWaitStart() { };
virtual void OnWaitEnd() { };
virtual void PrepareRender() { };

#ifdef PERF
REFERENCE_TIME m_trRenderStart; // Just before we started drawing
// Set in OnRenderStart, Used in OnRenderEnd
int m_idBaseStamp; // MSR_id for frame time stamp
int m_idBaseRenderTime; // MSR_id for true wait time
int m_idBaseAccuracy; // MSR_id for time frame is late (int)
#endif

// Quality management implementation for scheduling rendering

virtual BOOL ScheduleSample(IMediaSample *pMediaSample);
virtual HRESULT GetSampleTimes(IMediaSample *pMediaSample,
REFERENCE_TIME *pStartTime,
REFERENCE_TIME *pEndTime);

virtual HRESULT ShouldDrawSampleNow(IMediaSample *pMediaSample,
REFERENCE_TIME *ptrStart,
REFERENCE_TIME *ptrEnd);

// Lots of end of stream complexities

void TimerCallback();
void ResetEndOfStreamTimer();
HRESULT NotifyEndOfStream();
virtual HRESULT SendEndOfStream();
virtual HRESULT ResetEndOfStream();
virtual HRESULT EndOfStream();

// Rendering is based around the clock

void SignalTimerFired();
virtual HRESULT CancelNotification();
virtual HRESULT ClearPendingSample();

// Called when the filter changes state

virtual HRESULT Active();
virtual HRESULT Inactive();
virtual HRESULT StartStreaming();
virtual HRESULT StopStreaming();
virtual HRESULT BeginFlush();
virtual HRESULT EndFlush();

// Deal with connections and type changes

virtual HRESULT BreakConnect();
virtual HRESULT SetMediaType(const CMediaType *pmt);
virtual HRESULT CompleteConnect(IPin *pReceivePin);

// These look after the handling of data samples

virtual HRESULT PrepareReceive(IMediaSample *pMediaSample);
virtual HRESULT Receive(IMediaSample *pMediaSample);
virtual BOOL HaveCurrentSample();
virtual IMediaSample *GetCurrentSample();
virtual HRESULT Render(IMediaSample *pMediaSample);

// Derived classes MUST override these
virtual HRESULT DoRenderSample(IMediaSample *pMediaSample) PURE;
virtual HRESULT CheckMediaType(const CMediaType *) PURE;

// Helper
void WaitForReceiveToComplete();
};


// CBaseVideoRenderer is a renderer class (see its ancestor class) and
// it handles scheduling of media samples so that they are drawn at the
// correct time by the reference clock. It implements a degradation
// strategy. Possible degradation modes are:
// Drop frames here (only useful if the drawing takes significant time)
// Signal supplier (upstream) to drop some frame(s) - i.e. one-off skip.
// Signal supplier to change the frame rate - i.e. ongoing skipping.
// Or any combination of the above.
// In order to determine what's useful to try we need to know what's going
// on. This is done by timing various operations (including the supplier).
// This timing is done by using timeGetTime as it is accurate enough and
// usually cheaper than calling the reference clock. It also tells the
// truth if there is an audio break and the reference clock stops.
// We provide a number of public entry points (named OnXxxStart, OnXxxEnd)
// which the rest of the renderer calls at significant moments. These do
// the timing.

// the number of frames that the sliding averages are averaged over.
// the rule is (1024*NewObservation + (AVGPERIOD-1) * PreviousAverage)/AVGPERIOD
#define AVGPERIOD 4
#define DO_MOVING_AVG(avg,obs) (avg = (1024*obs + (AVGPERIOD-1)*avg)/AVGPERIOD)
// Spot the bug in this macro - I can't. but it doesn't work!

class CBaseVideoRenderer : public CBaseRenderer, // Base renderer class
public IQualProp, // Property page guff
public IQualityControl // Allow throttling
{
protected:

// Hungarian:
// tFoo is the time Foo in mSec (beware m_tStart from filter.h)
// trBar is the time Bar by the reference clock

//******************************************************************
// State variables to control synchronisation
//******************************************************************

// Control of sending Quality messages. We need to know whether
// we are in trouble (e.g. frames being dropped) and where the time
// is being spent.

// When we drop a frame we play the next one early.
// The frame after that is likely to wait before drawing and counting this
// wait as spare time is unfair, so we count it as a zero wait.
// We therefore need to know whether we are playing frames early or not.

int m_nNormal; // The number of consecutive frames
// drawn at their normal time (not early)
// -1 means we just dropped a frame.

#ifdef PERF
BOOL m_bDrawLateFrames; // Don't drop any frames (debug and I'm
// not keen on people using it!)
#endif

BOOL m_bSupplierHandlingQuality;// The response to Quality messages says
// our supplier is handling things.
// We will allow things to go extra late
// before dropping frames. We will play
// very early after he has dropped one.

// Control of scheduling, frame dropping etc.
// We need to know where the time is being spent so as to tell whether
// we should be taking action here, signalling supplier or what.
// The variables are initialised to a mode of NOT dropping frames.
// They will tell the truth after a few frames.
// We typically record a start time for an event, later we get the time
// again and subtract to get the elapsed time, and we average this over
// a few frames. The average is used to tell what mode we are in.

// Although these are reference times (64 bit) they are all DIFFERENCES
// between times which are small. An int will go up to 214 secs before
// overflow. Avoiding 64 bit multiplications and divisions seems
// worth while.



// Audio-video throttling. If the user has turned up audio quality
// very high (in principle it could be any other stream, not just audio)
// then we can receive cries for help via the graph manager. In this case
// we put in a wait for some time after rendering each frame.
int m_trThrottle;

// The time taken to render (i.e. BitBlt) frames controls which component
// needs to degrade. If the blt is expensive, the renderer degrades.
// If the blt is cheap it's done anyway and the supplier degrades.
int m_trRenderAvg; // Time frames are taking to blt
int m_trRenderLast; // Time for last frame blt
int m_tRenderStart; // Just before we started drawing (mSec)
// derived from timeGetTime.

// When frames are dropped we will play the next frame as early as we can.
// If it was a false alarm and the machine is fast we slide gently back to
// normal timing. To do this, we record the offset showing just how early
// we really are. This will normally be negative meaning early or zero.
int m_trEarliness;

// Target provides slow long-term feedback to try to reduce the
// average sync offset to zero. Whenever a frame is actually rendered
// early we add a msec or two, whenever late we take off a few.
// We add or take off 1/32 of the error time.
// Eventually we should be hovering around zero. For a really bad case
// where we were (say) 300mSec off, it might take 100 odd frames to
// settle down. The rate of change of this is intended to be slower
// than any other mechanism in Quartz, thereby avoiding hunting.
int m_trTarget;

// The proportion of time spent waiting for the right moment to blt
// controls whether we bother to drop a frame or whether we reckon that
// we're doing well enough that we can stand a one-frame glitch.
int m_trWaitAvg; // Average of last few wait times
// (actually we just average how early
// we were). Negative here means LATE.

// The average inter-frame time.
// This is used to calculate the proportion of the time used by the
// three operations (supplying us, waiting, rendering)
int m_trFrameAvg; // Average inter-frame time
int m_trDuration; // duration of last frame.

#ifdef PERF
// Performance logging identifiers
int m_idTimeStamp; // MSR_id for frame time stamp
int m_idEarliness; // MSR_id for earliness fudge
int m_idTarget; // MSR_id for Target fudge
int m_idWaitReal; // MSR_id for true wait time
int m_idWait; // MSR_id for wait time recorded
int m_idFrameAccuracy; // MSR_id for time frame is late (int)
int m_idRenderAvg; // MSR_id for Render time recorded (int)
int m_idSchLateTime; // MSR_id for lateness at scheduler
int m_idQualityRate; // MSR_id for Quality rate requested
int m_idQualityTime; // MSR_id for Quality time requested
int m_idDecision; // MSR_id for decision code
int m_idDuration; // MSR_id for duration of a frame
int m_idThrottle; // MSR_id for audio-video throttling
//int m_idDebug; // MSR_id for trace style debugging
//int m_idSendQuality; // MSR_id for timing the notifications per se
#endif // PERF
REFERENCE_TIME m_trRememberStampForPerf; // original time stamp of frame
// with no earliness fudges etc.
#ifdef PERF
REFERENCE_TIME m_trRememberFrameForPerf; // time when previous frame rendered

// debug...
int m_idFrameAvg;
int m_idWaitAvg;
#endif

// PROPERTY PAGE
// This has edit fields that show the user what's happening
// These member variables hold these counts.

int m_cFramesDropped; // cumulative frames dropped IN THE RENDERER
int m_cFramesDrawn; // Frames since streaming started seen BY THE
// RENDERER (some may be dropped upstream)

// Next two support average sync offset and standard deviation of sync offset.
LONGLONG m_iTotAcc; // Sum of accuracies in mSec
LONGLONG m_iSumSqAcc; // Sum of squares of (accuracies in mSec)

// Next two allow jitter calculation. Jitter is std deviation of frame time.
REFERENCE_TIME m_trLastDraw; // Time of prev frame (for inter-frame times)
LONGLONG m_iSumSqFrameTime; // Sum of squares of (inter-frame time in mSec)
LONGLONG m_iSumFrameTime; // Sum of inter-frame times in mSec

// To get performance statistics on frame rate, jitter etc, we need
// to record the lateness and inter-frame time. What we actually need are the
// data above (sum, sum of squares and number of entries for each) but the data
// is generated just ahead of time and only later do we discover whether the
// frame was actually drawn or not. So we have to hang on to the data
int m_trLate; // hold onto frame lateness
int m_trFrame; // hold onto inter-frame time

int m_tStreamingStart; // if streaming then time streaming started
// else time of last streaming session
// used for property page statistics
#ifdef PERF
LONGLONG m_llTimeOffset; // timeGetTime()*10000+m_llTimeOffset==ref time
#endif

public:


CBaseVideoRenderer(REFCLSID RenderClass, // CLSID for this renderer
TCHAR *pName, // Debug ONLY description
LPUNKNOWN pUnk, // Aggregated owner object
HRESULT *phr); // General OLE return code

~CBaseVideoRenderer();

// IQualityControl methods - Notify allows audio-video throttling

STDMETHODIMP SetSink( IQualityControl * piqc);
STDMETHODIMP Notify( IBaseFilter * pSelf, Quality q);

// These provide a full video quality management implementation

void OnRenderStart(IMediaSample *pMediaSample);
void OnRenderEnd(IMediaSample *pMediaSample);
void OnWaitStart();
void OnWaitEnd();
HRESULT OnStartStreaming();
HRESULT OnStopStreaming();
void ThrottleWait();

// Handle the statistics gathering for our quality management

void PreparePerformanceData(int trLate, int trFrame);
virtual void RecordFrameLateness(int trLate, int trFrame);
virtual void OnDirectRender(IMediaSample *pMediaSample);
virtual HRESULT ResetStreamingTimes();
BOOL ScheduleSample(IMediaSample *pMediaSample);
HRESULT ShouldDrawSampleNow(IMediaSample *pMediaSample,
REFERENCE_TIME *ptrStart,
REFERENCE_TIME *ptrEnd);

virtual HRESULT SendQuality(REFERENCE_TIME trLate, REFERENCE_TIME trRealStream);
STDMETHODIMP JoinFilterGraph(IFilterGraph * pGraph, LPCWSTR pName);

//
// Do estimates for standard deviations for per-frame
// statistics
//
// *piResult = (llSumSq - iTot * iTot / m_cFramesDrawn - 1) /
// (m_cFramesDrawn - 2)
// or 0 if m_cFramesDrawn <= 3
//
HRESULT GetStdDev(
int nSamples,
int *piResult,
LONGLONG llSumSq,
LONGLONG iTot
);
public:

// IQualProp property page support

STDMETHODIMP get_FramesDroppedInRenderer(int *cFramesDropped);
STDMETHODIMP get_FramesDrawn(int *pcFramesDrawn);
STDMETHODIMP get_AvgFrameRate(int *piAvgFrameRate);
STDMETHODIMP get_Jitter(int *piJitter);
STDMETHODIMP get_AvgSyncOffset(int *piAvg);
STDMETHODIMP get_DevSyncOffset(int *piDev);

// Implement an IUnknown interface and expose IQualProp

DECLARE_IUNKNOWN
STDMETHODIMP NonDelegatingQueryInterface(REFIID riid,VOID **ppv);
};

#endif // __RENBASE__