FMediaSampleCache Class Reference

#include <MediaSampleCache.h>

Public Member Functions
MEDIAUTILS_API	FMediaSampleCache ()
MEDIAUTILS_API void	Empty ()
MEDIAUTILS_API TSharedPtr< IMediaAudioSample, ESPMode::ThreadSafe >	GetAudioSample (FTimespan Time)
MEDIAUTILS_API void	GetCachedAudioSampleRanges (TRangeSet< FTimespan > &OutTimeRanges) const
MEDIAUTILS_API void	GetCachedVideoSampleRanges (TRangeSet< FTimespan > &OutTimeRanges) const
MEDIAUTILS_API void	GetOverlaySamples (FTimespan Time, TArray< TSharedPtr< IMediaOverlaySample, ESPMode::ThreadSafe > > &OutSamples)
MEDIAUTILS_API TSharedPtr< IMediaTextureSample, ESPMode::ThreadSafe >	GetVideoSample (FTimespan Time, bool Forward)
void	SetCacheWindow (FTimespan Ahead, FTimespan Behind)
MEDIAUTILS_API void	Tick (FTimespan DeltaTime, float Rate, FTimespan Time)

Detailed Description

Implements a cache for media samples.

Constructor & Destructor Documentation

FMediaSampleCache()

FMediaSampleCache::FMediaSampleCache

(

)

Default constructor.

Member Function Documentation

Empty()

void FMediaSampleCache::Empty

(

)

Empty the cache.

See also

Update

GetAudioSample()

TSharedPtr< IMediaAudioSample, ESPMode::ThreadSafe > FMediaSampleCache::GetAudioSample

(

FTimespan

Time

)

Get the audio sample for the specified play time.

This method returns the sample that contains the specified time code.

Parameters

Time	The time to get the sample for (in the player's clock).

Returns

The sample, or nullptr if no sample available.

See also

GetAudioSamples, GetCachedVideoSampleRanges, GetOverlaySamples

GetCachedAudioSampleRanges()

void FMediaSampleCache::GetCachedAudioSampleRanges

(

TRangeSet< FTimespan > &

OutTimeRanges

)

const

Get the time ranges of audio samples currently in the cache.

Parameters

OutTimeRanges

Will contain the set of cached sample time ranges.

See also

GetAudioSample, GetCachedVideoSampleRanges

GetCachedVideoSampleRanges()

void FMediaSampleCache::GetCachedVideoSampleRanges

(

TRangeSet< FTimespan > &

OutTimeRanges

)

const

Get the time ranges of video samples currently in the cache.

Parameters

OutTimeRanges

Will contain the set of cached sample time ranges.

See also

GetCachedAudioSampleRanges, GetVideoSample

GetOverlaySamples()

void FMediaSampleCache::GetOverlaySamples	(	FTimespan	Time,
		TArray< TSharedPtr< IMediaOverlaySample, ESPMode::ThreadSafe > > &	OutSamples
	)

Get the text overlay samples for the specified time.

Parameters

Time	The time to get the sample for (in the player's clock).
OutSamples	Will contain the overlay samples.

See also

GetAudioSample, GetVideoSample

GetVideoSample()

TSharedPtr< IMediaTextureSample, ESPMode::ThreadSafe > FMediaSampleCache::GetVideoSample	(	FTimespan	Time,
		bool	Forward
	)

Get the video sample for the specified play time.

This method will return the closest match for the given time code. If the current play rate is positive, the closest sample with an equal or older time is returned. If the current rate is negative, the closest sample with an equal or newer time is returned.

Parameters

Time	The time to get the sample for (in the player's clock).
Forward	Whether the play direction is forward (true) or backward (false).

Returns

The sample, or nullptr if no sample available.

See also

GetAudioSample, GetCachedVideoSampleRanges, GetOverlaySamples

SetCacheWindow()

void FMediaSampleCache::SetCacheWindow ( FTimespan  Ahead, FTimespan  Behind  )

inline

Set the time window of samples to cache.

Parameters

Ahead	Maximum time of samples to cache ahead of the play position.
Behind	Maximum time of samples to cache behind the play position.

Tick()

void FMediaSampleCache::Tick	(	FTimespan	DeltaTime,
		float	Rate,
		FTimespan	Time
	)

Tick the cache.

This method fetches any unconsumed media samples from the player and removes expired samples from the cache.

Parameters

DeltaTime	Time since the last tick.
Rate	The current play rate.
Time	The current play time.

See also

Initialize, Shutdown

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The documentation for this class was generated from the following files:

• Engine/Source/Runtime/MediaUtils/Public/MediaSampleCache.h
• Engine/Source/Runtime/MediaUtils/Private/MediaSampleCache.cpp