Qt 5.9 | Qt Multimedia | C++ Classes | QAbstractPlanarVideoBuffer

Qt 5.9.4 Reference Documentation

# QAbstractPlanarVideoBuffer Class

The QAbstractPlanarVideoBuffer class is an abstraction for planar video data. More...

Header: | #include <QAbstractPlanarVideoBuffer>
qmake: | QT += multimedia
Since: | Qt 5.4
Inherits: | QAbstractVideoBuffer

- List of all members, including inherited members

## Public Functions

| QAbstractPlanarVideoBuffer(HandleType type)
virtual | ~QAbstractPlanarVideoBuffer()
virtual int | map(MapMode mode, int *numBytes, int[4] bytesPerLine, uchar *[4] data) = 0

- 7 public functions inherited from QAbstractVideoBuffer

## Detailed Description

The QAbstractPlanarVideoBuffer class is an abstraction for planar video data.

QAbstractPlanarVideoBuffer extends QAbstractVideoBuffer to support mapping non-continuous planar video data. Implement this instead of QAbstractVideoBuffer when the abstracted video data stores planes in separate buffers or includes padding between planes which would interfere with calculating offsets from the bytes per line and frame height.

See also QAbstractVideoBuffer::mapPlanes().

## Member Function Documentation

### QAbstractPlanarVideoBuffer::QAbstractPlanarVideoBuffer(HandleType type)

Constructs an abstract planar video buffer of the given type.

### `[virtual]` QAbstractPlanarVideoBuffer::~QAbstractPlanarVideoBuffer()

Destroys an abstract planar video buffer.

### `[pure virtual]` int QAbstractPlanarVideoBuffer::map(MapMode mode, int *numBytes, int[4] bytesPerLine, uchar *[4] data)

Maps the contents of a video buffer to memory.

The map mode indicates whether the contents of the mapped memory should be read from and/or written to the buffer. If the map mode includes the `QAbstractVideoBuffer::ReadOnly` flag the mapped memory will be populated with the content of the buffer when initially mapped. If the map mode includes the `QAbstractVideoBuffer::WriteOnly` flag the content of the possibly modified mapped memory will be written back to the buffer when unmapped.

When access to the data is no longer needed be sure to call the unmap() function to release the mapped memory and possibly update the buffer contents.

Returns the number of planes in the mapped video data. For each plane the line stride of that plane will be returned in bytesPerLine, and a pointer to the plane data will be returned in data. The accumulative size of the mapped data is returned in numBytes.

See also QAbstractVideoBuffer::map(), QAbstractVideoBuffer::unmap(), and QAbstractVideoBuffer::mapMode().