QVideoFrameFormat Class

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

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

公共类型

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 }

公共函数

	QVideoFrameFormat ()
	QVideoFrameFormat (const QSize & size , QVideoFrameFormat::PixelFormat format )
	QVideoFrameFormat (const QVideoFrameFormat & other )
	QVideoFrameFormat (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	setMaxLuminance (float lum )
void	setMirrored (bool mirrored )
void	setScanLineDirection (QVideoFrameFormat::Direction direction )
void	setViewport (const QRect & viewport )
void	swap (QVideoFrameFormat & other )
QRect	viewport () const
bool	operator!= (const QVideoFrameFormat & other ) const
QVideoFrameFormat &	operator= (QVideoFrameFormat && other )
QVideoFrameFormat &	operator= (const QVideoFrameFormat & other )
bool	operator== (const QVideoFrameFormat & other ) const

静态公共成员

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

详细描述

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 set up 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().

成员类型文档编制

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.

常量	值	描述
`QVideoFrameFormat::ColorRange_Unknown`	`0`	The color range of the video is unknown.
`QVideoFrameFormat::ColorRange_Video`	`1`

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).

常量	值
`QVideoFrameFormat::ColorRange_Full`	`2`

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

enum QVideoFrameFormat:: ColorSpace

Enumerates the color space of video frames.

常量	值	描述
`QVideoFrameFormat::ColorSpace_Undefined`	`0`	No color space is specified.
`QVideoFrameFormat::ColorSpace_BT601`	`1`	A 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_BT709`	`2`	A 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_AdobeRgb`	`5`	The full range YUV color space used in most JPEG files.
`QVideoFrameFormat::ColorSpace_BT2020`	`6`	The color space defined by ITU-R BT.2020. Used mainly for HDR videos.

enum QVideoFrameFormat:: ColorTransfer

常量	值	描述
`QVideoFrameFormat::ColorTransfer_Unknown`	`0`	The color transfer function is unknown.
`QVideoFrameFormat::ColorTransfer_BT709`	`1`	Color 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_BT601`	`2`	Color values are encoded according to BT601. See also https://www.itu.int/rec/R-REC-BT.601/en.
`QVideoFrameFormat::ColorTransfer_Linear`	`3`	Color values are linear
`QVideoFrameFormat::ColorTransfer_Gamma22`	`4`	Color values are encoded with a gamma of 2.2
`QVideoFrameFormat::ColorTransfer_Gamma28`	`5`	Color values are encoded with a gamma of 2.8
`QVideoFrameFormat::ColorTransfer_ST2084`	`6`	Color 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_B67`	`7`	Color 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

枚举视频扫描线的布局方向。

常量	值	描述
`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

枚举视频数据类型。

常量	值	描述
`QVideoFrameFormat::Format_Invalid`	`0`	帧是无效的。
`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. This is currently only being used on Android.
`QVideoFrameFormat::Format_SamplerRect`	`30`	The 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_YUV420P10`	`31`	Similar to YUV420, but uses 16bits per component, 10 of those significant.

成员函数文档编制

QVideoFrameFormat:: QVideoFrameFormat ()

Constructs a null video stream format.

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

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

QVideoFrameFormat:: QVideoFrameFormat (const QVideoFrameFormat & other )

构造副本为 other .

`[noexcept]` QVideoFrameFormat:: QVideoFrameFormat ( QVideoFrameFormat && other )

Constructs a QVideoFrameFormat by moving from other .

`[noexcept]` 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.

另请参阅 setColorRange ().

QVideoFrameFormat::ColorSpace QVideoFrameFormat:: colorSpace () const

Returns the color space of a video stream.

另请参阅 setColorSpace ().

QVideoFrameFormat::ColorTransfer QVideoFrameFormat:: colorTransfer () const

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

另请参阅 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.

另请参阅 setFrameRate ().

QSize QVideoFrameFormat:: frameSize () const

返回视频流中帧的尺度。

另请参阅 setFrameSize (), frameWidth ()，和 frameHeight ().

int QVideoFrameFormat:: frameWidth () const

返回视频流中帧的宽度。

另请参阅 frameSize () 和 frameHeight ().

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

返回图像格式等效视频帧像素 format 。若没有等效格式 QImage::Format_Invalid 被返回取而代之。

注意： 一般而言 QImage 没有 YUV 格式。

bool QVideoFrameFormat:: isMirrored () const

返回 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.

注意： 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

返回视频流中帧的像素格式。

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

Returns a video pixel format equivalent to an image format 。若没有等效格式 QVideoFrameFormat::Format_Invalid 被返回取而代之。

注意： 一般而言 QImage 没有 YUV 格式。

`[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.

另请参阅 setScanLineDirection ().

void QVideoFrameFormat:: setColorRange ( QVideoFrameFormat::ColorRange range )

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

另请参阅 colorRange ().

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

设置 colorSpace of a video stream.

另请参阅 colorSpace ().

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

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

另请参阅 colorTransfer ().

void QVideoFrameFormat:: setFrameRate ( qreal rate )

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

另请参阅 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.

另请参阅 frameSize ().

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

这是重载函数。

设置 width and height of frames in a video stream.

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

void QVideoFrameFormat:: setMaxLuminance ( float lum )

Sets the maximum luminance to the given value, lum .

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.

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

另请参阅 isMirrored ().

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

设置 direction of scan lines.

另请参阅 scanLineDirection ().

void QVideoFrameFormat:: setViewport (const QRect & viewport )

Sets the viewport of a video stream to viewport .

另请参阅 viewport ().

`[noexcept]` void QVideoFrameFormat:: swap ( QVideoFrameFormat & other )

Swaps the current video frame format with the other .

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.

另请参阅 setViewport ().

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

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

`[noexcept]` QVideoFrameFormat &QVideoFrameFormat:: operator= ( QVideoFrameFormat && other )

移动 other 到此 QVideoFrameFormat .

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

Assigns the values of other 到此对象。

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

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