QVideoFrame¶

The QVideoFrame class represents a frame of video data. More…

Synopsis¶

Functions¶

def __eq__ (other)
def __ne__ (other)
def bytesPerLine (plane)
def endTime ()
def handleType ()
def height ()
def isMapped ()
def isReadable ()
def isValid ()
def isWritable ()
def map (mode)
def mapMode ()
def mappedBytes (plane)
def pixelFormat ()
def planeCount ()
def setEndTime (time)
def setStartTime (time)
def setSubtitleText (text)
def size ()
def startTime ()
def subtitleText ()
def surfaceFormat ()
def swap (other)
def textureHandle (plane)
def toImage ()
def unmap ()
def width ()

Detailed Description¶

A QVideoFrame encapsulates the pixel data of a video frame, and information about the frame.

Video frames can come from several places - decoded media , a camera , or generated programmatically. The way pixels are described in these frames can vary greatly, and some pixel formats offer greater compression opportunities at the expense of ease of use.

The pixel contents of a video frame can be mapped to memory using the map() function. After a successful call to map() , the video data can be accessed through various functions. Some of the YUV pixel formats provide the data in several planes. The planeCount() method will return the amount of planes that being used.

While mapped, the video data of each plane can accessed using the bits() function, which returns a pointer to a buffer. The size of this buffer is given by the mappedBytes() function, and the size of each line is given by bytesPerLine() . The return value of the handle() function may also be used to access frame data using the internal buffer’s native APIs (for example - an OpenGL texture handle).

A video frame can also have timestamp information associated with it. These timestamps can be used to determine when to start and stop displaying the frame.

QVideoFrame objects can consume a significant amount of memory or system resources and should not be held for longer than required by the application.

Note

Since video frames can be expensive to copy, QVideoFrame is explicitly shared, so any change made to a video frame will also apply to any copies.

class PySide6.QtMultimedia.QVideoFrame¶

PySide6.QtMultimedia.QVideoFrame(other)

PySide6.QtMultimedia.QVideoFrame(format)

Parameters

other – PySide6.QtMultimedia.QVideoFrame
format – PySide6.QtMultimedia.QVideoFrameFormat

Constructs a null video frame.

Constructs a video frame of the given pixel format.

PySide6.QtMultimedia.QVideoFrame.HandleType¶

Identifies the type of a video buffers handle.

Constant

Description

QVideoFrame.NoHandle

The buffer has no handle, its data can only be accessed by mapping the buffer.

QVideoFrame.RhiTextureHandle

The handle of the buffer is defined by The Qt Rendering Hardware Interface (RHI). RHI is Qt’s internal graphics abstraction for 3D APIs, such as OpenGL, Vulkan, Metal, and Direct 3D.

See also

handleType()

PySide6.QtMultimedia.QVideoFrame.MapMode¶

Enumerates how a video buffer’s data is mapped to system memory.

Constant

Description

QVideoFrame.NotMapped

The video buffer is not mapped to memory.

QVideoFrame.ReadOnly

The mapped memory is populated with data from the video buffer when mapped, but the content of the mapped memory may be discarded when unmapped.

QVideoFrame.WriteOnly

The mapped memory is uninitialized when mapped, but the possibly modified content will be used to populate the video buffer when unmapped.

QVideoFrame.ReadWrite

The mapped memory is populated with data from the video buffer, and the video buffer is repopulated with the content of the mapped memory when it is unmapped.

See also

mapMode() map()

New in version 6.1.

PySide6.QtMultimedia.QVideoFrame.bytesPerLine(plane)¶

Parameters: plane – int
Return type: int

Returns the number of bytes in a scan line of a plane.

This value is only valid while the frame data is mapped .

See also

bits() map() mappedBytes() planeCount()

PySide6.QtMultimedia.QVideoFrame.endTime()¶

Return type: int

Returns the presentation time (in microseconds) when a frame should stop being displayed.

An invalid time is represented as -1.

See also

setEndTime()

PySide6.QtMultimedia.QVideoFrame.handleType()¶

Return type: HandleType

Returns the type of a video frame’s handle.

The handle type could either be NoHandle , meaning that the frame is memory based, or a RHI texture.

PySide6.QtMultimedia.QVideoFrame.height()¶

Return type: int

Returns the height of a video frame.

PySide6.QtMultimedia.QVideoFrame.isMapped()¶

Return type: bool

Identifies if a video frame’s contents are currently mapped to system memory.

This is a convenience function which checks that the MapMode of the frame is not equal to NotMapped .

Returns true if the contents of the video frame are mapped to system memory, and false otherwise.

See also

mapMode() MapMode

PySide6.QtMultimedia.QVideoFrame.isReadable()¶

Return type: bool

Identifies if the mapped contents of a video frame were read from the frame when it was mapped.

This is a convenience function which checks if the MapMode contains the WriteOnly flag.

Returns true if the contents of the mapped memory were read from the video frame, and false otherwise.

See also

mapMode() MapMode

PySide6.QtMultimedia.QVideoFrame.isValid()¶

Return type: bool

Identifies whether a video frame is valid.

An invalid frame has no video buffer associated with it.

Returns true if the frame is valid, and false if it is not.

PySide6.QtMultimedia.QVideoFrame.isWritable()¶

Return type: bool

Identifies if the mapped contents of a video frame will be persisted when the frame is unmapped.

This is a convenience function which checks if the MapMode contains the WriteOnly flag.

Returns true if the video frame will be updated when unmapped, and false otherwise.

Note

The result of altering the data of a frame that is mapped in read-only mode is undefined. Depending on the buffer implementation the changes may be persisted, or worse alter a shared buffer.

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QVideoFrame¶

Synopsis¶

Functions¶

Detailed Description¶

Constant	Description
QVideoFrame.NoHandle	The buffer has no handle, its data can only be accessed by mapping the buffer.
QVideoFrame.RhiTextureHandle	The handle of the buffer is defined by The Qt Rendering Hardware Interface (RHI). RHI is Qt’s internal graphics abstraction for 3D APIs, such as OpenGL, Vulkan, Metal, and Direct 3D.

Constant	Description
QVideoFrame.NotMapped	The video buffer is not mapped to memory.
QVideoFrame.ReadOnly	The mapped memory is populated with data from the video buffer when mapped, but the content of the mapped memory may be discarded when unmapped.
QVideoFrame.WriteOnly	The mapped memory is uninitialized when mapped, but the possibly modified content will be used to populate the video buffer when unmapped.
QVideoFrame.ReadWrite	The mapped memory is populated with data from the video buffer, and the video buffer is repopulated with the content of the mapped memory when it is unmapped.