CpuVideoFramePool Class Reference

Recycles CPU-backed QVideoFrame storage keyed by (size, pixelFormat) to avoid per-frame malloc churn. More...

#include <CpuVideoFramePool.h>

Classes
struct	PlaneLayout

Public Member Functions
QVideoFrame	acquireFrame (const QVideoFrameFormat &format, const GstVideoInfo &info)
	Returns a pool-backed frame sized to info, or freshly allocates on a pool miss; invalid if unsupported.
quint64	hitCount () const noexcept
	Telemetry: total acquireFrame() calls satisfied from the pool vs. fresh alloc.
quint64	missCount () const noexcept
void	releaseBacking (QSize size, QVideoFrameFormat::PixelFormat format, QByteArray &&backing)
	Return a backing array to the pool; called by PooledCpuVideoBuffer's destructor only.

Static Public Member Functions
static CpuVideoFramePool &	instance ()
static std::unique_ptr< QAbstractVideoBuffer >	wrapZeroCopy (GstBuffer *buffer, const GstVideoInfo &info, const QVideoFrameFormat &format)
static PlaneLayout	computeLayout (const GstVideoInfo &info)
	Destination plane layout mirroring info (strides/offsets from the decoder). planeCount==0 means unsupported.
static QVideoFrame	copyFromBuffer (GstBuffer *buffer, const GstVideoInfo &videoInfo, const QVideoFrameFormat &format)
	Copy buffer's planes into a pool-allocated QVideoFrame; invalid on stride overflow or unsupported format.

Detailed Description

Recycles CPU-backed QVideoFrame storage keyed by (size, pixelFormat) to avoid per-frame malloc churn.

Definition at line 17 of file CpuVideoFramePool.h.

Member Function Documentation

acquireFrame()

QVideoFrame CpuVideoFramePool::acquireFrame	(	const QVideoFrameFormat &	format,
		const GstVideoInfo &	info
	)

Returns a pool-backed frame sized to info, or freshly allocates on a pool miss; invalid if unsupported.

Definition at line 230 of file CpuVideoFramePool.cc.

References CpuVideoFramePool::PlaneLayout::byteSize, computeLayout(), and CpuVideoFramePool::PlaneLayout::planeCount.

Referenced by copyFromBuffer().

computeLayout()

CpuVideoFramePool::PlaneLayout CpuVideoFramePool::computeLayout ( const GstVideoInfo &  info )

static

Destination plane layout mirroring info (strides/offsets from the decoder). planeCount==0 means unsupported.

Definition at line 157 of file CpuVideoFramePool.cc.

References CpuVideoFramePool::PlaneLayout::byteSize, CpuVideoFramePool::PlaneLayout::bytesPerLine, CpuVideoFramePool::PlaneLayout::height, CpuVideoFramePool::PlaneLayout::planeCount, and CpuVideoFramePool::PlaneLayout::planeOffset.

Referenced by acquireFrame().

copyFromBuffer()

QVideoFrame CpuVideoFramePool::copyFromBuffer ( GstBuffer *  buffer, const GstVideoInfo &  videoInfo, const QVideoFrameFormat &  format  )

static

Copy buffer's planes into a pool-allocated QVideoFrame; invalid on stride overflow or unsupported format.

Definition at line 260 of file CpuVideoFramePool.cc.

References acquireFrame(), and instance().

Referenced by mapSampleToFrame().

hitCount()

quint64 CpuVideoFramePool::hitCount ( ) const

inlinenoexcept

Telemetry: total acquireFrame() calls satisfied from the pool vs. fresh alloc.

Definition at line 31 of file CpuVideoFramePool.h.

instance()

CpuVideoFramePool & CpuVideoFramePool::instance ( )

static

Definition at line 151 of file CpuVideoFramePool.cc.

Referenced by copyFromBuffer().

missCount()

quint64 CpuVideoFramePool::missCount ( ) const

inlinenoexcept

Definition at line 33 of file CpuVideoFramePool.h.

releaseBacking()

void CpuVideoFramePool::releaseBacking	(	QSize	size,
		QVideoFrameFormat::PixelFormat	format,
		QByteArray &&	backing
	)

Return a backing array to the pool; called by PooledCpuVideoBuffer's destructor only.

Definition at line 198 of file CpuVideoFramePool.cc.

wrapZeroCopy()

std::unique_ptr< QAbstractVideoBuffer > CpuVideoFramePool::wrapZeroCopy ( GstBuffer *  buffer, const GstVideoInfo &  info, const QVideoFrameFormat &  format  )

static

Zero-copy CPU frame: wraps buffer and maps its system memory through to Qt. nullptr if not CPU-mappable (caller copies instead). Pins the decoder buffer for the frame's lifetime.

Definition at line 241 of file CpuVideoFramePool.cc.

Referenced by mapSampleToFrame().

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

• src/VideoManager/VideoReceiver/GStreamer/HwBuffers/common/CpuVideoFramePool.h
• src/VideoManager/VideoReceiver/GStreamer/HwBuffers/common/CpuVideoFramePool.cc