SampleGrabber.h

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/*
 * Copyright (c) Meta Platforms, Inc. and affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 */
 
#ifndef META_OCEAN_MEDIA_MF_SAMPLE_GRABBER_H
#define META_OCEAN_MEDIA_MF_SAMPLE_GRABBER_H
 
#include "ocean/media/mediafoundation/MediaFoundation.h"
 
#include "ocean/base/Callback.h"
 
namespace Ocean
{
 
namespace Media
{
 
namespace MediaFoundation
{
 
// Forward declaration.
class SampleGrabber;
 
/**
 * Definition of a scoped object holding a SampleGrabber object.
 * The wrapped SampleGrabber object will be released automatically once the scoped object does not exist anymore.
 * @ingroup mediamf
 */
typedef ScopedMediaFoundationObject<SampleGrabber> ScopedSampleGrabber;
 
/**
 * This class implements a callback interface.
 * @ingroup mediamf
 */
class SampleGrabber final : public IMFSampleGrabberSinkCallback
{
    public:
 
        /**
         * Definition of a callback for samples.
         */
        typedef Callback<void, const GUID&, const unsigned int, const long long, const long long, const void*, const unsigned int> SampleCallback;
 
    public:
 
        /**
         * Destructs this object.
         */
        virtual ~SampleGrabber() = default;
 
        /**
         * Deactivates the callback.
         */
        void deactivate();
 
        /**
         * Returns the time of the most recent sample.
         * @return The most recent sample time
         */
        LONGLONG recentSampleTime() const;
 
        /**
         * Interface query function.
         * @param iid The identifier of the interface being requested
         * @param ppv The address of a pointer variable that receives the interface pointer requested in the riid parameter
         * @return This method returns S_OK if the interface is supported
         */
        STDMETHODIMP QueryInterface(REFIID iid, void** ppv) override;
 
        /**
         * Increments the reference count for an interface on an object.
         * @return The method returns the new reference count
         */
        STDMETHODIMP_(ULONG) AddRef() override;
 
        /**
         * Decrements the reference count for an interface on an object.
         * @return The method returns the new reference count
         */
        STDMETHODIMP_(ULONG) Release() override;
 
        /**
         * Called when the presentation clock starts.
         * @param hnsSystemTime The system time when the clock started, in 100-nanosecond units
         * @param llClockStartOffset The new starting time for the clock, in 100-nanosecond units
         * @return If this method succeeds, it returns S_OK
         */
        STDMETHODIMP OnClockStart(MFTIME hnsSystemTime, LONGLONG llClockStartOffset) override;
 
        /**
         * Called when the presentation clock stops.
         * @param hnsSystemTime The system time when the clock stopped, in 100-nanosecond units
         * @return If this method succeeds, it returns S_OK
         */
        STDMETHODIMP OnClockStop(MFTIME hnsSystemTime) override;
 
        /**
         * Called when the presentation clock pauses.
         * @param hnsSystemTime The system time when the clock was paused, in 100-nanosecond units
         * @return If this method succeeds, it returns S_OK
         */
        STDMETHODIMP OnClockPause(MFTIME hnsSystemTime) override;
 
        /**
         * Called when the presentation clock restarts from the same position while paused.
         * @param hnsSystemTime The system time when the clock restarted, in 100-nanosecond units
         * @return If this method succeeds, it returns S_OK
         */
        STDMETHODIMP OnClockRestart(MFTIME hnsSystemTime) override;
 
        /**
         * Called when the rate changes on the presentation clock.
         * @param hnsSystemTime The system time when the rate was set, in 100-nanosecond units
         * @param flRate The new rate, as a multiplier of the normal playback rate
         * @return If this method succeeds, it returns S_OK
         */
        STDMETHODIMP OnClockSetRate(MFTIME hnsSystemTime, float flRate) override;
 
        /**
         * Called when the presentation clock is set on the sample-grabber sink.
         * @param pClock Pointer to the presentation clock's IMFPresentationClock interface
         * @return If this method succeeds, it returns S_OK
         */
        STDMETHODIMP OnSetPresentationClock(IMFPresentationClock* pClock) override;
 
        /**
         * Called when the sample-grabber sink receives a new media sample.
         * @param guidMajorMediaType The major type that specifies the format of the data
         * @param dwSampleFlags Reserved
         * @param llSampleTime The presentation time for this sample, in 100-nanosecond units
         * @param llSampleDuration The duration of the sample, in 100-nanosecond units
         * @param pSampleBuffer A pointer to a buffer that contains the sample data
         * @param dwSampleSize Size of the pSampleBuffer buffer, in bytes
         */
        STDMETHODIMP OnProcessSample(REFGUID guidMajorMediaType, DWORD dwSampleFlags, LONGLONG llSampleTime, LONGLONG llSampleDuration, const BYTE * pSampleBuffer, DWORD dwSampleSize) override;
 
        /**
         * Called when the sample-grabber sink is shut down.
         * @return If this method succeeds, it returns S_OK
         */
        STDMETHODIMP OnShutdown() override;
 
        /**
         * Creates a new instance of the sample grabber.
         * @param sampleCallback Sample callback function
         * @return Resulting sample grabber
         */
        static ScopedSampleGrabber createInstance(const SampleCallback& sampleCallback);
 
    private:
 
        /**
         * Default constructor.
         * @param callback Sample callback function
         */
        SampleGrabber(const SampleCallback& callback);
 
    private:
 
        /// The reference counter.
        long referenceCounter_ = 1;
 
        /// Sample callback function.
        SampleCallback sampleCallback_;
 
        /// True if the callback is active.
        bool active_ = true;
 
        /// The time of the most recent sample.
        LONGLONG recentSampleTime_ = LONGLONG(-1);
};
 
}
 
}
 
}
 
#endif // META_OCEAN_MEDIA_MF_SAMPLE_GRABBER_H