QVideoFrameFormat Class

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

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

Public Types

enum ColorRange { ColorRange_Unknown, ColorRange_Video, ColorRange_Full }
enum ColorSpace { ColorSpace_Undefined, ColorSpace_BT601, ColorSpace_BT709, ColorSpace_AdobeRgb, ColorSpace_BT2020 }
enum ColorTransfer { ColorTransfer_Unknown, ColorTransfer_BT709, ColorTransfer_BT601, ColorTransfer_Linear, ColorTransfer_Gamma22, …, ColorTransfer_STD_B67 }
enum Direction { TopToBottom, BottomToTop }
enum PixelFormat { Format_Invalid, Format_ARGB8888, Format_ARGB8888_Premultiplied, Format_XRGB8888, Format_BGRA8888, …, Format_YUV420P10 }

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()
QVideoFrameFormat::ColorRange colorRange() const
QVideoFrameFormat::ColorSpace colorSpace() const
QVideoFrameFormat::ColorTransfer colorTransfer() const
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 setColorRange(QVideoFrameFormat::ColorRange range)
void setColorSpace(QVideoFrameFormat::ColorSpace colorSpace)
void setColorTransfer(QVideoFrameFormat::ColorTransfer colorTransfer)
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)
QRect viewport() 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::ColorRange

Describes the color range used by the video data. Video data usually comes in either full color range, where all values are being used, or a more limited range traditionally used in YUV video formats, where a subset of all values is being used.

ConstantValueDescription
QVideoFrameFormat::ColorRange_Unknown0The color range of the video is unknown.
QVideoFrameFormat::ColorRange_Video1 

The color range traditionally used by most YUV video formats. For 8 bit formats, the Y component is limited to values between 16 and 235. The U and V components are limited to values between 16 and 240

For higher bit depths multiply these values with 2^(depth-8).

ConstantValue
QVideoFrameFormat::ColorRange_Full2

Full color range. All values from 0 to 2^depth - 1 are valid.

enum QVideoFrameFormat::ColorSpace

Enumerates the color space of video frames.

ConstantValueDescription
QVideoFrameFormat::ColorSpace_Undefined0No color space is specified.
QVideoFrameFormat::ColorSpace_BT6011A 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 mostly by older videos that were targeting CRT displays.
QVideoFrameFormat::ColorSpace_BT7092A color space defined by ITU-R BT.709 with the same values range as ColorSpace_BT601. The most commonly used color space today.
QVideoFrameFormat::ColorSpace_AdobeRgb5The full range YUV color space used in most JPEG files.
QVideoFrameFormat::ColorSpace_BT20206The color space defined by ITU-R BT.2020. Used mainly for HDR videos.

enum QVideoFrameFormat::ColorTransfer

ConstantValueDescription
QVideoFrameFormat::ColorTransfer_Unknown0The color transfer function is unknown.
QVideoFrameFormat::ColorTransfer_BT7091Color values are encoded according to BT709. See also https://www.itu.int/rec/R-REC-BT.709/en. This is close to, but not identical to a gamma curve of 2.2, and the same transfer curve as is used in sRGB.
QVideoFrameFormat::ColorTransfer_BT6012Color values are encoded according to BT601. See also https://www.itu.int/rec/R-REC-BT.601/en.
QVideoFrameFormat::ColorTransfer_Linear3Color values are linear
QVideoFrameFormat::ColorTransfer_Gamma224Color values are encoded with a gamma of 2.2
QVideoFrameFormat::ColorTransfer_Gamma285Color values are encoded with a gamma of 2.8
QVideoFrameFormat::ColorTransfer_ST20846Color values are encoded using STME ST 2084. This transfer function is the most common HDR transfer function and often called the 'perceptual quantizer'. See also https://www.itu.int/rec/R-REC-BT.2100 and https://en.wikipedia.org/wiki/Perceptual_quantizer.
QVideoFrameFormat::ColorTransfer_STD_B677Color values are encoded using ARIB STD B67. This transfer function is also often referred to as 'hybrid log gamma'. See also https://www.itu.int/rec/R-REC-BT.2100 and https://en.wikipedia.org/wiki/Hybrid_log–gamma.

enum QVideoFrameFormat::Direction

Enumerates the layout direction of video scan lines.

ConstantValueDescription
QVideoFrameFormat::TopToBottom0Scan lines are arranged from the top of the frame to the bottom.
QVideoFrameFormat::BottomToTop1Scan lines are arranged from the bottom of the frame to the top.

enum QVideoFrameFormat::PixelFormat

Enumerates video data types.

ConstantValueDescription
QVideoFrameFormat::Format_Invalid0The frame is invalid.
QVideoFrameFormat::Format_ARGB88881The frame is stored using a ARGB format with 8 bits per component.
QVideoFrameFormat::Format_ARGB8888_Premultiplied2The frame stored using a premultiplied ARGB format with 8 bits per component.
QVideoFrameFormat::Format_XRGB88883The frame stored using a 32 bits per pixel RGB format (0xff, R, G, B).
QVideoFrameFormat::Format_BGRA88884The frame is stored using a 32-bit BGRA format (0xBBGGRRAA).
QVideoFrameFormat::Format_BGRA8888_Premultiplied5The frame is stored using a premultiplied 32bit BGRA format.
QVideoFrameFormat::Format_ABGR88887The frame is stored using a 32-bit ABGR format (0xAABBGGRR).
QVideoFrameFormat::Format_XBGR88888The frame is stored using a 32-bit BGR format (0xffBBGGRR).
QVideoFrameFormat::Format_RGBA88889The 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_BGRX88886The frame is stored in format 32-bit BGRx format, [31:0] B:G:R:x 8:8:8:8 little endian
QVideoFrameFormat::Format_RGBX888810The 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_AYUV11The frame is stored using a packed 32-bit AYUV format (0xAAYYUUVV).
QVideoFrameFormat::Format_AYUV_Premultiplied12The frame is stored using a packed premultiplied 32-bit AYUV format (0xAAYYUUVV).
QVideoFrameFormat::Format_YUV420P13The 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_YUV422P14The 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_YV1215The 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_UYVY16The 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_YUYV17The 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_NV1218The 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_NV2119The 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_IMC120The 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_IMC221The 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_IMC322The 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_IMC423The 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_P01026The 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_P01627The 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_Y824The frame is stored using an 8-bit greyscale format.
QVideoFrameFormat::Format_Y1625The frame is stored using a 16-bit linear greyscale format. Little endian.
QVideoFrameFormat::Format_Jpeg29The frame is stored in compressed Jpeg format.
QVideoFrameFormat::Format_SamplerExternalOES28The frame is stored in external OES texture format. This is currently only being used on Android.
QVideoFrameFormat::Format_SamplerRect30The frame is stored in rectangle texture format (GL_TEXTURE_RECTANGLE). This is only being used on macOS with an OpenGL based Rendering Hardware interface. The underlying pixel format stored in the texture is Format_BRGA8888.
QVideoFrameFormat::Format_YUV420P1031Similar to YUV420, but uses 16bits per component, 10 of those significant.

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.

QVideoFrameFormat::ColorRange QVideoFrameFormat::colorRange() const

Returns the color range that should be used to render the video stream.

See also setColorRange().

QVideoFrameFormat::ColorSpace QVideoFrameFormat::colorSpace() const

Returns the color space of a video stream.

See also setColorSpace().

QVideoFrameFormat::ColorTransfer QVideoFrameFormat::colorTransfer() const

Returns the color transfer function that should be used to render the video stream.

See also setColorTransfer().

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::setColorRange(QVideoFrameFormat::ColorRange range)

Sets the color transfer range that should be used to render the video stream to range.

See also colorRange().

void QVideoFrameFormat::setColorSpace(QVideoFrameFormat::ColorSpace colorSpace)

Sets the colorSpace of a video stream.

See also colorSpace().

void QVideoFrameFormat::setColorTransfer(QVideoFrameFormat::ColorTransfer colorTransfer)

Sets the color transfer function that should be used to render the video stream to colorTransfer.

See also colorTransfer().

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().

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().

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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