baseclass.pas

本系统是基于企业局域网平台针对企业安防

    // --- TBCBaseOutputPin ------------

    function QueryId(out Id: PWideChar): HRESULT; override; stdcall;
    // Grab and release extra interfaces if required
    function CheckConnect(Pin: IPin): HRESULT; override;
    function BreakConnect: HRESULT; override;
    function CompleteConnect(ReceivePin: IPin): HRESULT; override;

    // check that we can support this output type
    function CheckMediaType(mtOut: PAMMediaType): HRESULT; override;

    // set the connection media type
    function SetMediaType(pmt: PAMMediaType): HRESULT; override;

    // called from CBaseOutputPin during connection to ask for
    // the count and size of buffers we need.
    function DecideBufferSize(Alloc: IMemAllocator; Prop: PAllocatorProperties): HRESULT; override;

    // returns the preferred formats for a pin
    function GetMediaType(Position: integer; out MediaType: PAMMediaType): HRESULT; override;

    // inherited from IQualityControl via CBasePin
    function Notify(Sendr: IBaseFilter; q: TQuality): HRESULT; override; stdcall;
  end;

// milenko start (added TBCVideoTransformFilter conversion)
  TBCVideoTransformFilter = class(TBCTransformFilter)
  public
    constructor Create(Name: WideString; Unk: IUnknown; clsid: TGUID);
    destructor Destroy; override;
    function EndFlush: HRESULT; override;

    // =================================================================
    // ----- override these bits ---------------------------------------
    // =================================================================
    // The following methods are in CTransformFilter which is inherited.
    // They are mentioned here for completeness
    //
    // These MUST be supplied in a derived class
    //
    // NOTE:
    // virtual HRESULT Transform(IMediaSample * pIn, IMediaSample *pOut);
    // virtual HRESULT CheckInputType(const CMediaType* mtIn) PURE;
    // virtual HRESULT CheckTransform
    //     (const CMediaType* mtIn, const CMediaType* mtOut) PURE;
    // static CCOMObject * CreateInstance(LPUNKNOWN, HRESULT *);
    // virtual HRESULT DecideBufferSize
    //     (IMemAllocator * pAllocator, ALLOCATOR_PROPERTIES *pprop) PURE;
    // virtual HRESULT GetMediaType(int iPosition, CMediaType *pMediaType) PURE;
    //
    // These MAY also be overridden
    //
    // virtual HRESULT StopStreaming();
    // virtual HRESULT SetMediaType(PIN_DIRECTION direction,const CMediaType *pmt);
    // virtual HRESULT CheckConnect(PIN_DIRECTION dir,IPin *pPin);
    // virtual HRESULT BreakConnect(PIN_DIRECTION dir);
    // virtual HRESULT CompleteConnect(PIN_DIRECTION direction,IPin *pReceivePin);
    // virtual HRESULT EndOfStream(void);
    // virtual HRESULT BeginFlush(void);
    // virtual HRESULT EndFlush(void);
    // virtual HRESULT NewSegment
    //     (REFERENCE_TIME tStart,REFERENCE_TIME tStop,double dRate);
  {$IFDEF PERF}
    // If you override this - ensure that you register all these ids
    // as well as any of your own,
    procedure RegisterPerfId; virtual;
  {$ENDIF}
  protected
    // =========== QUALITY MANAGEMENT IMPLEMENTATION ========================
    // Frames are assumed to come in three types:
    // Type 1: an AVI key frame or an MPEG I frame.
    //        This frame can be decoded with no history.
    //        Dropping this frame means that no further frame can be decoded
    //        until the next type 1 frame.
    //        Type 1 frames are sync points.
    // Type 2: an AVI non-key frame or an MPEG P frame.
    //        This frame cannot be decoded unless the previous type 1 frame was
    //        decoded and all type 2 frames since have been decoded.
    //        Dropping this frame means that no further frame can be decoded
    //        until the next type 1 frame.
    // Type 3: An MPEG B frame.
    //        This frame cannot be decoded unless the previous type 1 or 2 frame
    //        has been decoded AND the subsequent type 1 or 2 frame has also
    //        been decoded.  (This requires decoding the frames out of sequence).
    //        Dropping this frame affects no other frames.  This implementation
    //        does not allow for these.  All non-sync-point frames are treated
    //        as being type 2.
    //
    // The spacing of frames of type 1 in a file is not guaranteed.  There MUST
    // be a type 1 frame at (well, near) the start of the file in order to start
    // decoding at all.  After that there could be one every half second or so,
    // there could be one at the start of each scene (aka "cut", "shot") or
    // there could be no more at all.
    // If there is only a single type 1 frame then NO FRAMES CAN BE DROPPED
    // without losing all the rest of the movie.  There is no way to tell whether
    // this is the case, so we find that we are in the gambling business.
    // To try to improve the odds, we record the greatest interval between type 1s
    // that we have seen and we bet on things being no worse than this in the
    // future.

    // You can tell if it's a type 1 frame by calling IsSyncPoint().
    // there is no architected way to test for a type 3, so you should override
    // the quality management here if you have B-frames.

    FKeyFramePeriod: integer; // the largest observed interval between type 1 frames
                              // 1 means every frame is type 1, 2 means every other.

    FFramesSinceKeyFrame: integer; // Used to count frames since the last type 1.
                                   // becomes the new m_nKeyFramePeriod if greater.

    FSkipping: Boolean;           // we are skipping to the next type 1 frame

  {$IFDEF PERF}
    FidFrameType: integer;          // MSR id Frame type.  1=Key, 2="non-key"
    FidSkip: integer;               // MSR id skipping
    FidLate: integer;               // MSR id lateness
    FidTimeTillKey: integer;        // MSR id for guessed time till next key frame.
  {$ENDIF}

    FitrLate: integer;          // lateness from last Quality message
                                // (this overflows at 214 secs late).
    FtDecodeStart: integer;     // timeGetTime when decode started.
    FitrAvgDecode: integer;     // Average decode time in reference units.

    FNoSkip: Boolean;            // debug - no skipping.

    // We send an EC_QUALITY_CHANGE notification to the app if we have to degrade.
    // We send one when we start degrading, not one for every frame, this means
    // we track whether we've sent one yet.
    FQualityChanged: Boolean;

    // When non-zero, don't pass anything to renderer until next keyframe
    // If there are few keys, give up and eventually draw something
    FWaitForKey: integer;

    function AbortPlayback(hr: HRESULT): HRESULT;  // if something bad happens
    function ShouldSkipFrame(pIn: IMediaSample): Boolean;
  public
    function StartStreaming: HRESULT; override;
    function Receive(Sample: IMediaSample): HRESULT; override;
    function AlterQuality(const q: TQuality): HRESULT; override;
  end;
// milenko end

  TBCTransInPlaceOutputPin = class;
  TBCTransInPlaceInputPin  = class;

  TBCTransInPlaceFilter = class(TBCTransformFilter)
  public
    // map getpin/getpincount for base enum of pins to owner
    // override this to return more specialised pin objects
    function GetPin(n: integer): TBCBasePin; override;

    //  Set bModifiesData == false if your derived filter does
    //  not modify the data samples (for instance it's just copying
    //  them somewhere else or looking at the timestamps).
    constructor Create(ObjectName: string; unk: IUnKnown; clsid: TGUID;
      out hr: HRESULT; ModifiesData: boolean = True);

    constructor CreateFromFactory(Factory: TBCClassFactory; const Controller: IUnknown); override;

    // The following are defined to avoid undefined pure virtuals.
    // Even if they are never called, they will give linkage warnings/errors

    // We override EnumMediaTypes to bypass the transform class enumerator
    // which would otherwise call this.
    function GetMediaType(Position: integer; out MediaType: PAMMediaType): HRESULT; override;

    // This is called when we actually have to provide out own allocator.
    function DecideBufferSize(Alloc: IMemAllocator; propInputRequest: PAllocatorProperties): HRESULT; override;

    // The functions which call this in CTransform are overridden in this
    // class to call CheckInputType with the assumption that the type
    // does not change.  In Debug builds some calls will be made and
    // we just ensure that they do not assert.
    function CheckTransform(mtIn, mtOut: PAMMediaType): HRESULT; override;

    // =================================================================
    // ----- You may want to override this -----------------------------
    // =================================================================

    function CompleteConnect(dir: TPinDirection; ReceivePin: IPin): HRESULT; override;

    // chance to customize the transform process
    function Receive(Sample: IMediaSample): HRESULT; override;

    // =================================================================
    // ----- You MUST override these -----------------------------------
    // =================================================================

    function Transform(Sample: IMediaSample): HRESULT; reintroduce; virtual; abstract;

    // this goes in the factory template table to create new instances
    // static CCOMObject * CreateInstance(LPUNKNOWN, HRESULT *);

  protected
    FModifiesData: boolean; // Does this filter change the data?
    function Copy(Source: IMediaSample): IMediaSample;

    // these hold our input and output pins
    function InputPin: TBCTransInPlaceInputPin;
    function OutputPin: TBCTransInPlaceOutputPin;

    //  Helper to see if the input and output types match
    function TypesMatch: boolean;

    //  Are the input and output allocators different?
    function UsingDifferentAllocators: boolean;
  end;

  TBCTransInPlaceInputPin = class(TBCTransformInputPin)
  protected
    FTIPFilter: TBCTransInPlaceFilter; // our filter
    FReadOnly : boolean;               // incoming stream is read only
  public
    constructor Create(ObjectName: string; Filter: TBCTransInPlaceFilter;
      out hr: HRESULT; Name: WideString);
    // --- IMemInputPin -----
    // Provide an enumerator for media types by getting one from downstream
    function EnumMediaTypes(out ppEnum: IEnumMediaTypes): HRESULT; override; stdcall;

    // Say whether media type is acceptable.
    function CheckMediaType(pmt: PAMMediaType): HRESULT; override;

    // Return our upstream allocator
    function GetAllocator(out Allocator: IMemAllocator): HRESULT; stdcall;

    // get told which allocator the upstream output pin is actually
    // going to use.
    function NotifyAllocator(Allocator: IMemAllocator; ReadOnly: BOOL): HRESULT; stdcall;

    // Allow the filter to see what allocator we have
    // N.B. This does NOT AddRef
    function PeekAllocator: IMemAllocator;

    // Pass this on downstream if it ever gets called.
    function GetAllocatorRequirements(props: PAllocatorProperties): HRESULT; stdcall;

    property ReadOnly: Boolean read FReadOnly;
  end;


// ==================================================
// Implements the output pin
// ==================================================

  TBCTransInPlaceOutputPin = class(TBCTransformOutputPin)
  protected
    // m_pFilter points to our CBaseFilter
    FTIPFilter: TBCTransInPlaceFilter;
  public
    constructor Create(ObjectName: string; Filter: TBCTransInPlaceFilter;
      out hr: HRESULT; Name: WideString);

    // --- CBaseOutputPin ------------

    // negotiate the allocator and its buffer size/count
    // Insists on using our own allocator.  (Actually the one upstream of us).
    // We don't override this - instead we just agree the default
    // then let the upstream filter decide for itself on reconnect
    // virtual HRESULT DecideAllocator(IMemInputPin * pPin, IMemAllocator ** pAlloc);

    // Provide a media type enumerator.  Get it from upstream.
    function EnumMediaTypes(out ppEnum: IEnumMediaTypes): HRESULT; override; stdcall;

    // Say whether media type is acceptable.
    function CheckMediaType(pmt: PAMMediaType): HRESULT; override;

    //  This just saves the allocator being used on the output pin
    //  Also called by input pin's GetAllocator()
    procedure SetAllocator(Allocator: IMemAllocator);

    function ConnectedIMemInputPin: IMemInputPin;

    // Allow the filter to see what allocator we have
    // N.B. This does NOT AddRef
    function PeekAllocator: IMemAllocator;
  end;


  TBCBasePropertyPage = class(TBCUnknown, IPropertyPage)
  private
    FObjectSet: boolean;          // SetObject has been called or not.
  protected
    FPageSite: IPropertyPageSite; // Details for our property site
    FDirty: boolean;              // Has anything been changed
    FForm: TFormPropertyPage;
  public