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TVideoFrameBuffer Class Reference

class TVideoFrameBuffer

TVideoFrameBuffer represents a buffer for a single decoded video picture. The buffer must be contained within a chunk that can be shared across processes.

The frame buffer class is used both for video renderer data flow and with the MMMFVideoClientBufferSupport extension.

Public Member Functions
	TVideoFrameBuffer (const TUncompressedVideoFormat &, TInt , TInt , const RChunk &, TInt )
IMPORT_C TUint8 *	Buffer ()
IMPORT_C TInt	BufferId ()
TBufferStatus	BufferStatus ()
IMPORT_C const RChunk &	Chunk ()
TDblQueLink &	DblQueLink ()
IMPORT_C TUncompressedVideoFormat	Format ()
TTime	PresentationTime ()
void	SetBufferStatus ( TBufferStatus )
void	SetPresentationTime (const TTime &)
IMPORT_C TUint	Stride ()

Public Member Enumerations
enum	TBufferStatus { EAvailable , EUsedByClient , EWaiting , ESubmitted }

Public Attributes
const TInt	iOffset

Private Attributes
TInt	iBufferId
RChunk	iChunk
TDblQueLink	iDblQueLink
TUncompressedVideoFormat	iFormat
TInt	iOffsetInChunk
TTime	iPresentationTime
TBufferStatus	iStatus
TInt	iStride

Constructor & Destructor Documentation

TVideoFrameBuffer(const TUncompressedVideoFormat &, TInt, TInt, const RChunk &, TInt)

IMPORT_C	TVideoFrameBuffer	(	const TUncompressedVideoFormat &	aFormat,
			TInt	aStride,
			TInt	aBufferId,
			const RChunk &	aChunk,
			TInt	aOffsetInChunk
		)

Constructor

Parameters

const TUncompressedVideoFormat & aFormat	Data format for the buffer.
TInt aStride	Stride for the buffer, i.e. the number of bytes from the start of one pixel row to the next.
TInt aBufferId	Buffer identifier, set by the buffer allocator. Buffer IDs are used to identify buffers in e.g. buffer rendering notifications.
const RChunk & aChunk	The chunk where the buffer is located. Note that the TVideoFrame Buffer does not take ownership of the RChunk.
TInt aOffsetInChunk	Offset from the beginning of the chunk for this buffer, in bytes.

Member Functions Documentation

Buffer()

IMPORT_C TUint8 *

Buffer

(

)

const

Returns a pointer to buffer data as mapped to the current process s address space.

BufferId()

IMPORT_C TInt

BufferId

(

)

const

Returns the buffer identifier of the buffer. Buffer IDs are used to identify buffers.

BufferStatus()

TBufferStatus

BufferStatus

(

)

const

Returns the buffer status.

Chunk()

IMPORT_C const RChunk &

Chunk

(

)

const

Returns the RChunk where the buffer is located. The RChunk can be shared between several TVideoFrameBuffers.

DblQueLink()

TDblQueLink &

DblQueLink

(

)

Returns the queue link for use by video renderer.

Format()

IMPORT_C TUncompressedVideoFormat

Format

(

)

const

Returns the data format of the buffer. For YUV formats, typically only TUncompressedVideoFormat.iYuvFormat.iDataLayout and iPattern are valid.

PresentationTime()

TTime

PresentationTime

(

)

const

Returns presentation time.

SetBufferStatus(TBufferStatus)

void

SetBufferStatus

(

TBufferStatus

aStatus

)

Set buffer status.

Parameters

TBufferStatus aStatus

Buffer status set by video renderer

SetPresentationTime(const TTime &)

void

SetPresentationTime

(

const TTime &

aTime

)

Set presentation time.

Parameters

const TTime & aTime

Presentation time

Stride()

IMPORT_C TUint

Stride

(

)

const

Returns the stride of the buffer. This is the number of bytes from the start of one pixel row to the next. The stride is commonly equal to bytes_per_pixel*width, but can be larger if the buffer requires padding. With planar YUV data the stride refers to luminance (Y) stride. Chrominance (U & V) stride is iStride/2.