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QVideoFrameFormat Class

The QVideoFrameFormat class specifies the stream format of a video presentation surface. More...

Header: #include <QVideoFrameFormat>
CMake: find_package(Qt6 COMPONENTS Multimedia REQUIRED) target_link_libraries(mytarget PRIVATE Qt6::Multimedia)
qmake: QT += multimedia

Public Types

enum Direction { TopToBottom, BottomToTop }
enum PixelFormat { Format_Invalid, Format_ARGB8888, Format_ARGB8888_Premultiplied, Format_XRGB8888, Format_BGRA8888, …, Format_SamplerRect }
enum YCbCrColorSpace { YCbCr_Undefined, YCbCr_BT601, YCbCr_BT709, YCbCr_xvYCC601, YCbCr_xvYCC709, YCbCr_JPEG }

Public Functions

QVideoFrameFormat(QVideoFrameFormat &&other)
QVideoFrameFormat(const QVideoFrameFormat &other)
QVideoFrameFormat(const QSize &size, QVideoFrameFormat::PixelFormat format)
QVideoFrameFormat()
QVideoFrameFormat & operator=(const QVideoFrameFormat &other)
QVideoFrameFormat & operator=(QVideoFrameFormat &&other)
~QVideoFrameFormat()
int frameHeight() const
qreal frameRate() const
QSize frameSize() const
int frameWidth() const
bool isMirrored() const
bool isValid() const
QVideoFrameFormat::PixelFormat pixelFormat() const
int planeCount() const
QVideoFrameFormat::Direction scanLineDirection() const
void setFrameRate(qreal rate)
void setFrameSize(const QSize &size)
void setFrameSize(int width, int height)
void setMirrored(bool mirrored)
void setScanLineDirection(QVideoFrameFormat::Direction direction)
void setViewport(const QRect &viewport)
void setYCbCrColorSpace(QVideoFrameFormat::YCbCrColorSpace space)
QRect viewport() const
QVideoFrameFormat::YCbCrColorSpace yCbCrColorSpace() const
bool operator!=(const QVideoFrameFormat &other) const
bool operator==(const QVideoFrameFormat &other) const

Static Public Members

QImage::Format imageFormatFromPixelFormat(QVideoFrameFormat::PixelFormat format)
QVideoFrameFormat::PixelFormat pixelFormatFromImageFormat(QImage::Format format)
QString pixelFormatToString(QVideoFrameFormat::PixelFormat pixelFormat)

Detailed Description

A video sink presents a stream of video frames. QVideoFrameFormat describes the type of the frames and determines how they should be presented.

The core properties of a video stream required to setup a video sink are the pixel format given by pixelFormat(), and the frame dimensions given by frameSize().

The region of a frame that is actually displayed on a video surface is given by the viewport(). A stream may have a viewport less than the entire region of a frame to allow for videos smaller than the nearest optimal size of a video frame. For example the width of a frame may be extended so that the start of each scan line is eight byte aligned.

Other common properties are the scanLineDirection(), frameRate() and the yCrCbColorSpace().

Member Type Documentation

enum QVideoFrameFormat::Direction

Enumerates the layout direction of video scan lines.

Constant Value Description
QVideoFrameFormat::TopToBottom 0 Scan lines are arranged from the top of the frame to the bottom.
QVideoFrameFormat::BottomToTop 1 Scan lines are arranged from the bottom of the frame to the top.

enum QVideoFrameFormat::PixelFormat

Enumerates video data types.

Constant Value Description
QVideoFrameFormat::Format_Invalid 0 The frame is invalid.
QVideoFrameFormat::Format_ARGB8888 1 The frame is stored using a ARGB format with 8 bits per component.
QVideoFrameFormat::Format_ARGB8888_Premultiplied 2 The frame stored using a premultiplied ARGB format with 8 bits per component.
QVideoFrameFormat::Format_XRGB8888 3 The frame stored using a 32 bits per pixel RGB format (0xff, R, G, B).
QVideoFrameFormat::Format_BGRA8888 4 The frame is stored using a 32-bit BGRA format (0xBBGGRRAA).
QVideoFrameFormat::Format_BGRA8888_Premultiplied 5 The frame is stored using a premultiplied 32bit BGRA format.
QVideoFrameFormat::Format_ABGR8888 7 The frame is stored using a 32-bit ABGR format (0xAABBGGRR).
QVideoFrameFormat::Format_XBGR8888 8 The frame is stored using a 32-bit BGR format (0xffBBGGRR).
QVideoFrameFormat::Format_RGBA8888 9 The frame is stored in memory as the bytes R, G, B, A/X, with R at the lowest address and A/X at the highest address.
QVideoFrameFormat::Format_BGRX8888 6 The frame is stored in format 32-bit BGRx format, [31:0] B:G:R:x 8:8:8:8 little endian
QVideoFrameFormat::Format_RGBX8888 10 The frame is stored in memory as the bytes R, G, B, A/X, with R at the lowest address and A/X at the highest address.
QVideoFrameFormat::Format_AYUV 11 The frame is stored using a packed 32-bit AYUV format (0xAAYYUUVV).
QVideoFrameFormat::Format_AYUV_Premultiplied 12 The frame is stored using a packed premultiplied 32-bit AYUV format (0xAAYYUUVV).
QVideoFrameFormat::Format_YUV420P 13 The frame is stored using an 8-bit per component planar YUV format with the U and V planes horizontally and vertically sub-sampled, i.e. the height and width of the U and V planes are half that of the Y plane.
QVideoFrameFormat::Format_YUV422P 14 The frame is stored using an 8-bit per component planar YUV format with the U and V planes horizontally sub-sampled, i.e. the width of the U and V planes are half that of the Y plane, and height of U and V planes is the same as Y.
QVideoFrameFormat::Format_YV12 15 The frame is stored using an 8-bit per component planar YVU format with the V and U planes horizontally and vertically sub-sampled, i.e. the height and width of the V and U planes are half that of the Y plane.
QVideoFrameFormat::Format_UYVY 16 The frame is stored using an 8-bit per component packed YUV format with the U and V planes horizontally sub-sampled (U-Y-V-Y), i.e. two horizontally adjacent pixels are stored as a 32-bit macropixel which has a Y value for each pixel and common U and V values.
QVideoFrameFormat::Format_YUYV 17 The frame is stored using an 8-bit per component packed YUV format with the U and V planes horizontally sub-sampled (Y-U-Y-V), i.e. two horizontally adjacent pixels are stored as a 32-bit macropixel which has a Y value for each pixel and common U and V values.
QVideoFrameFormat::Format_NV12 18 The frame is stored using an 8-bit per component semi-planar YUV format with a Y plane (Y) followed by a horizontally and vertically sub-sampled, packed UV plane (U-V).
QVideoFrameFormat::Format_NV21 19 The frame is stored using an 8-bit per component semi-planar YUV format with a Y plane (Y) followed by a horizontally and vertically sub-sampled, packed VU plane (V-U).
QVideoFrameFormat::Format_IMC1 20 The frame is stored using an 8-bit per component planar YUV format with the U and V planes horizontally and vertically sub-sampled. This is similar to the Format_YUV420P type, except that the bytes per line of the U and V planes are padded out to the same stride as the Y plane.
QVideoFrameFormat::Format_IMC2 21 The frame is stored using an 8-bit per component planar YUV format with the U and V planes horizontally and vertically sub-sampled. This is similar to the Format_YUV420P type, except that the lines of the U and V planes are interleaved, i.e. each line of U data is followed by a line of V data creating a single line of the same stride as the Y data.
QVideoFrameFormat::Format_IMC3 22 The frame is stored using an 8-bit per component planar YVU format with the V and U planes horizontally and vertically sub-sampled. This is similar to the Format_YV12 type, except that the bytes per line of the V and U planes are padded out to the same stride as the Y plane.
QVideoFrameFormat::Format_IMC4 23 The frame is stored using an 8-bit per component planar YVU format with the V and U planes horizontally and vertically sub-sampled. This is similar to the Format_YV12 type, except that the lines of the V and U planes are interleaved, i.e. each line of V data is followed by a line of U data creating a single line of the same stride as the Y data.
QVideoFrameFormat::Format_P010 26 The frame is stored using a 16bit per component semi-planar YUV format with a Y plane (Y) followed by a horizontally and vertically sub-sampled, packed UV plane (U-V). Only the 10 most significant bits of each component are being used.
QVideoFrameFormat::Format_P016 27 The frame is stored using a 16bit per component semi-planar YUV format with a Y plane (Y) followed by a horizontally and vertically sub-sampled, packed UV plane (U-V).
QVideoFrameFormat::Format_Y8 24 The frame is stored using an 8-bit greyscale format.
QVideoFrameFormat::Format_Y16 25 The frame is stored using a 16-bit linear greyscale format. Little endian.
QVideoFrameFormat::Format_Jpeg 29 The frame is stored in compressed Jpeg format.
QVideoFrameFormat::Format_SamplerExternalOES 28 The frame is stored in external OES texture format.
QVideoFrameFormat::Format_SamplerRect 30 The frame is stored in rectangle texture format.

enum QVideoFrameFormat::YCbCrColorSpace

Enumerates the Y'CbCr color space of video frames.

Constant Value Description
QVideoFrameFormat::YCbCr_Undefined 0 No color space is specified.
QVideoFrameFormat::YCbCr_BT601 1 A Y'CbCr color space defined by ITU-R recommendation BT.601 with Y value range from 16 to 235, and Cb/Cr range from 16 to 240. Used in standard definition video.
QVideoFrameFormat::YCbCr_BT709 2 A Y'CbCr color space defined by ITU-R BT.709 with the same values range as YCbCr_BT601. Used for HDTV.
QVideoFrameFormat::YCbCr_xvYCC601 3 The BT.601 color space with the value range extended to 0 to 255. It is backward compatible with BT.601 and uses values outside BT.601 range to represent a wider range of colors.
QVideoFrameFormat::YCbCr_xvYCC709 4 The BT.709 color space with the value range extended to 0 to 255.
QVideoFrameFormat::YCbCr_JPEG 5 The full range Y'CbCr color space used in JPEG files.

Member Function Documentation

QVideoFrameFormat::QVideoFrameFormat(QVideoFrameFormat &&other)

Constructs a QVideoFrameFormat by moving from other.

QVideoFrameFormat::QVideoFrameFormat(const QVideoFrameFormat &other)

Constructs a copy of other.

QVideoFrameFormat::QVideoFrameFormat(const QSize &size, QVideoFrameFormat::PixelFormat format)

Constructs a video stream with the given frame size and pixel format.

QVideoFrameFormat::QVideoFrameFormat()

Constructs a null video stream format.

QVideoFrameFormat &QVideoFrameFormat::operator=(const QVideoFrameFormat &other)

Assigns the values of other to this object.

QVideoFrameFormat &QVideoFrameFormat::operator=(QVideoFrameFormat &&other)

Moves other into this QVideoFrameFormat.

QVideoFrameFormat::~QVideoFrameFormat()

Destroys a video stream description.

int QVideoFrameFormat::frameHeight() const

Returns the height of frame in a video stream.

qreal QVideoFrameFormat::frameRate() const

Returns the frame rate of a video stream in frames per second.

See also setFrameRate().

QSize QVideoFrameFormat::frameSize() const

Returns the dimensions of frames in a video stream.

See also setFrameSize(), frameWidth(), and frameHeight().

int QVideoFrameFormat::frameWidth() const

Returns the width of frames in a video stream.

See also frameSize() and frameHeight().

[static] QImage::Format QVideoFrameFormat::imageFormatFromPixelFormat(QVideoFrameFormat::PixelFormat format)

Returns an image format equivalent to a video frame pixel format. If there is no equivalent format QImage::Format_Invalid is returned instead.

Note: In general QImage does not handle YUV formats.

bool QVideoFrameFormat::isMirrored() const

Returns true if the surface is mirrored around its vertical axis. This is typically needed for video frames coming from a front camera of a mobile device.

Note: The mirroring here differs from QImage::mirrored, as a vertically mirrored QImage will be mirrored around its x-axis.

bool QVideoFrameFormat::isValid() const

Identifies if a video surface format has a valid pixel format and frame size.

Returns true if the format is valid, and false otherwise.

QVideoFrameFormat::PixelFormat QVideoFrameFormat::pixelFormat() const

Returns the pixel format of frames in a video stream.

[static] QVideoFrameFormat::PixelFormat QVideoFrameFormat::pixelFormatFromImageFormat(QImage::Format format)

Returns a video pixel format equivalent to an image format. If there is no equivalent format QVideoFrameFormat::Format_Invalid is returned instead.

Note: In general QImage does not handle YUV formats.

[static] QString QVideoFrameFormat::pixelFormatToString(QVideoFrameFormat::PixelFormat pixelFormat)

Returns a string representation of the given pixelFormat.

int QVideoFrameFormat::planeCount() const

Returns the number of planes used. This number is depending on the pixel format and is 1 for RGB based formats, and a number between 1 and 3 for YUV based formats.

QVideoFrameFormat::Direction QVideoFrameFormat::scanLineDirection() const

Returns the direction of scan lines.

See also setScanLineDirection().

void QVideoFrameFormat::setFrameRate(qreal rate)

Sets the frame rate of a video stream in frames per second.

See also frameRate().

void QVideoFrameFormat::setFrameSize(const QSize &size)

Sets the size of frames in a video stream to size.

This will reset the viewport() to fill the entire frame.

See also frameSize().

void QVideoFrameFormat::setFrameSize(int width, int height)

This is an overloaded function.

Sets the width and height of frames in a video stream.

This will reset the viewport() to fill the entire frame.

void QVideoFrameFormat::setMirrored(bool mirrored)

Sets if the surface is mirrored around its vertical axis. This is typically needed for video frames coming from a front camera of a mobile device. Default value is false.

Note: The mirroring here differs from QImage::mirrored, as a vertically mirrored QImage will be mirrored around its x-axis.

See also isMirrored().

void QVideoFrameFormat::setScanLineDirection(QVideoFrameFormat::Direction direction)

Sets the direction of scan lines.

See also scanLineDirection().

void QVideoFrameFormat::setViewport(const QRect &viewport)

Sets the viewport of a video stream to viewport.

See also viewport().

void QVideoFrameFormat::setYCbCrColorSpace(QVideoFrameFormat::YCbCrColorSpace space)

Sets the Y'CbCr color space of a video stream. It is only used with raw YUV frame types.

See also yCbCrColorSpace().

QRect QVideoFrameFormat::viewport() const

Returns the viewport of a video stream.

The viewport is the region of a video frame that is actually displayed.

By default the viewport covers an entire frame.

See also setViewport().

QVideoFrameFormat::YCbCrColorSpace QVideoFrameFormat::yCbCrColorSpace() const

Returns the Y'CbCr color space of a video stream.

See also setYCbCrColorSpace().

bool QVideoFrameFormat::operator!=(const QVideoFrameFormat &other) const

Returns true if other is different to this video format, and false if they are the same.

bool QVideoFrameFormat::operator==(const QVideoFrameFormat &other) const

Returns true if other is the same as this video format, and false if they are different.

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https://doc.qt.io/qt-6.2/qvideoframeformat.html