The QVideoFrame class provides a representation of a frame of video data. 更多...
| 头： | #include <QVideoFrame> |
| Since: | Qt 4.6 |
| enum | FieldType { ProgressiveFrame, TopField, BottomField, InterlacedFrame } |
| enum | PixelFormat { Format_Invalid, Format_ARGB32, Format_ARGB32_Premultiplied, Format_RGB32, ..., Format_User } |
| QVideoFrame () | |
| QVideoFrame (QAbstractVideoBuffer * buffer , const QSize & size , PixelFormat format ) | |
| QVideoFrame (int bytes , const QSize & size , int bytesPerLine , PixelFormat format ) | |
| QVideoFrame (const QImage & image ) | |
| QVideoFrame (const QVideoFrame & other ) | |
| ~QVideoFrame () | |
| uchar * | bits () |
| const uchar * | bits () const |
| int | bytesPerLine () const |
| qint64 | endTime () const |
| FieldType | fieldType () const |
| QVariant | handle () const |
| QAbstractVideoBuffer::HandleType | handleType () const |
| int | height () const |
| bool | isMapped () const |
| bool | isReadable () const |
| bool | isValid () const |
| bool | isWritable () const |
| bool | map (QAbstractVideoBuffer::MapMode mode ) |
| QAbstractVideoBuffer::MapMode | mapMode () const |
| int | mappedBytes () const |
| PixelFormat | pixelFormat () const |
| void | setEndTime (qint64 time ) |
| void | setFieldType (FieldType field ) |
| void | setStartTime (qint64 time ) |
| QSize | size () const |
| qint64 | startTime () const |
| void | unmap () |
| int | width () const |
| QVideoFrame & | operator= (const QVideoFrame & other ) |
| QImage::Format | imageFormatFromPixelFormat (PixelFormat format ) |
| PixelFormat | pixelFormatFromImageFormat (QImage::Format format ) |
The QVideoFrame class provides a representation of a frame of video data.
A QVideoFrame encapsulates the data of a video frame, and information about the frame.
The contents of a video frame can be mapped to memory using the map () function. While mapped the video data can accessed using the bits () function which returns a pointer to a buffer, the total size of which is given by the mappedBytes (), and the size of each line is given by bytesPerLine (). The return value of the handle () function may be used to access frame data using the internal buffer's native APIs.
The video data in a QVideoFrame is encapsulated in a QAbstractVideoBuffer 。 QVideoFrame may be constructed from any buffer type by subclassing the QAbstractVideoBuffer 类。
注意： QVideoFrame is explicitly shared, any change made to video frame will also apply to any copies.
Specifies the field an interlaced video frame belongs to.
| 常量 | 值 | 描述 |
|---|---|---|
QVideoFrame::ProgressiveFrame
|
0
|
The frame is not interlaced. |
QVideoFrame::TopField
|
1
|
The frame contains a top field. |
QVideoFrame::BottomField
|
2
|
The frame contains a bottom field. |
QVideoFrame::InterlacedFrame
|
3
|
The frame contains a merged top and bottom field. |
枚举视频数据类型。
| 常量 | 值 | 描述 |
|---|---|---|
QVideoFrame::Format_Invalid
|
0
|
帧是无效的。 |
QVideoFrame::Format_ARGB32
|
1
|
The frame is stored using a 32-bit ARGB format (0xAARRGGBB). This is equivalent to QImage::Format_ARGB32 . |
QVideoFrame::Format_ARGB32_Premultiplied
|
2
|
The frame stored using a premultiplied 32-bit ARGB format (0xAARRGGBB). This is equivalent to QImage::Format_ARGB32_Premultiplied . |
QVideoFrame::Format_RGB32
|
3
|
The frame stored using a 32-bit RGB format (0xffRRGGBB). This is equivalent to QImage::Format_RGB32 |
QVideoFrame::Format_RGB24
|
4
|
The frame is stored using a 24-bit RGB format (8-8-8). This is equivalent to QImage::Format_RGB888 |
QVideoFrame::Format_RGB565
|
5
|
The frame is stored using a 16-bit RGB format (5-6-5). This is equivalent to QImage::Format_RGB16 . |
QVideoFrame::Format_RGB555
|
6
|
The frame is stored using a 16-bit RGB format (5-5-5). This is equivalent to QImage::Format_RGB555 . |
QVideoFrame::Format_ARGB8565_Premultiplied
|
7
|
The frame is stored using a 24-bit premultiplied ARGB format (8-6-6-5). |
QVideoFrame::Format_BGRA32
|
8
|
The frame is stored using a 32-bit ARGB format (0xBBGGRRAA). |
QVideoFrame::Format_BGRA32_Premultiplied
|
9
|
The frame is stored using a premultiplied 32bit BGRA format. |
QVideoFrame::Format_BGR32
|
10
|
The frame is stored using a 32-bit BGR format (0xBBGGRRff). |
QVideoFrame::Format_BGR24
|
11
|
The frame is stored using a 24-bit BGR format (0xBBGGRR). |
QVideoFrame::Format_BGR565
|
12
|
帧使用 16 位 BGR 格式 (5-6-5) 存储。 |
QVideoFrame::Format_BGR555
|
13
|
帧使用 16 位 BGR 格式 (5-5-5) 存储。 |
QVideoFrame::Format_BGRA5658_Premultiplied
|
14
|
The frame is stored using a 24-bit premultiplied BGRA format (5-6-5-8). |
QVideoFrame::Format_AYUV444
|
15
|
The frame is stored using a packed 32-bit AYUV format (0xAAYYUUVV). |
QVideoFrame::Format_AYUV444_Premultiplied
|
16
|
The frame is stored using a packed premultiplied 32-bit AYUV format (0xAAYYUUVV). |
QVideoFrame::Format_YUV444
|
17
|
The frame is stored using a 24-bit packed YUV format (8-8-8). |
QVideoFrame::Format_YUV420P
|
18
|
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. |
QVideoFrame::Format_YV12
|
19
|
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. |
QVideoFrame::Format_UYVY
|
20
|
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. |
QVideoFrame::Format_YUYV
|
21
|
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. |
QVideoFrame::Format_NV12
|
22
|
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). |
QVideoFrame::Format_NV21
|
23
|
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). |
QVideoFrame::Format_IMC1
|
24
|
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. |
QVideoFrame::Format_IMC2
|
25
|
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. |
QVideoFrame::Format_IMC3
|
26
|
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. |
QVideoFrame::Format_IMC4
|
27
|
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. |
QVideoFrame::Format_Y8
|
28
|
The frame is stored using an 8-bit greyscale format. |
QVideoFrame::Format_Y16
|
29
|
The frame is stored using a 16-bit linear greyscale format. Little endian. |
QVideoFrame::Format_User
|
1000
|
用户定义像素格式的起始值。 |
构造 null 视频帧。
构造视频帧从 buffer of the given pixel format and size (以像素为单位)。
注意： This doesn't increment the reference count of the video buffer.
Constructs a video frame of the given pixel format and size (以像素为单位)。
The bytesPerLine (stride) is the length of each scan line in bytes, and bytes is the total number of bytes that must be allocated for the frame.
Constructs a video frame from an image .
注意： This will construct an invalid video frame if there is no frame type equivalent to the image format.
另请参阅 pixelFormatFromImageFormat ().
构造副本为 other .
销毁视频帧。
返回指向帧数据缓冲起始的指针。
此值才有效当帧数据为 mapped .
另请参阅 map (), mappedBytes ()，和 bytesPerLine ().
返回指向帧数据缓冲起始的指针。
此值才有效当帧数据为 mapped .
另请参阅 map (), mappedBytes ()，和 bytesPerLine ().
返回扫描行字节数。
注意： This is the bytes per line of the first plane only. The bytes per line of subsequent planes should be calculated as per the frame type.
此值才有效当帧数据为 mapped .
另请参阅 bits (), map ()，和 mappedBytes ().
Returns the presentation time when a frame should stop being displayed.
另请参阅 setEndTime ().
Returns the field an interlaced video frame belongs to.
If the video is not interlaced this will return WholeFrame.
另请参阅 setFieldType ().
返回视频帧缓冲的特定类型句柄。
For an OpenGL texture this would be the texture ID.
另请参阅 QAbstractVideoBuffer::handle ().
返回视频帧的句柄类型。
返回视频帧的高度。
[static]
QImage::Format
QVideoFrame::
imageFormatFromPixelFormat
(
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。
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 QAbstractVideoBuffer::NotMapped .
Returns true if the contents of the video frame are mapped to system memory, and false otherwise.
另请参阅 mapMode () 和 QAbstractVideoBuffer::MapMode .
Identifies if the mapped contents of a video frame were read from the frame when it was mapped.
这是方便校验函数若 MapMode 包含 QAbstractVideoBuffer::WriteOnly 标志。
Returns true if the contents of the mapped memory were read from the video frame, and false otherwise.
另请参阅 mapMode () 和 QAbstractVideoBuffer::MapMode .
标识视频帧是否有效。
无效帧没有关联它的视频缓冲。
返回 true 若帧有效，和 false 若帧无效。
Identifies if the mapped contents of a video frame will be persisted when the frame is unmapped.
这是方便校验函数若 MapMode 包含 QAbstractVideoBuffer::WriteOnly 标志。
Returns true if the video frame will be updated when unmapped, and false otherwise.
注意： 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.
另请参阅 mapMode () 和 QAbstractVideoBuffer::MapMode .
Maps the contents of a video frame to memory.
映射 mode 指示映射内存内容是否应读取自和/或写入帧。若映射模式包括 QAbstractVideoBuffer::ReadOnly flag the mapped memory will be populated with the content of the video frame when mapped. If the map mode inclues the QAbstractVideoBuffer::WriteOnly flag the content of the mapped memory will be persisted in the frame when unmapped.
当映射时，可以直接访问视频帧内容透过指针返回通过 bits () 函数。
When access to the data is no longer needed be sure to call the unmap () function to release the mapped memory.
Returns true if the buffer was mapped to memory in the given mode 和 false 否则。
另请参阅 unmap (), mapMode ()，和 bits ().
返回将视频帧映射到系统内存中的模式。
另请参阅 map () 和 QAbstractVideoBuffer::MapMode .
返回由映射帧数据所占据的字节数。
此值才有效当帧数据为 mapped .
另请参阅 map ().
返回视频帧的颜色格式。
[static]
PixelFormat
QVideoFrame::
pixelFormatFromImageFormat
(
QImage::Format
format
)
Returns an video pixel format equivalent to an image format . If there is no equivalent format QVideoFrame::InvalidType is returned instead.
设置呈现 time when a frame should stop being displayed.
另请参阅 endTime ().
设置 field 属于隔行扫描视频帧。
另请参阅 fieldType ().
设置呈现 time when the frame should be displayed.
另请参阅 startTime ().
Returns the size of a video frame.
Returns the presentation time when the frame should be displayed.
另请参阅 setStartTime ().
释放的内存映射通过 map () 函数。
若 MapMode 包括 QAbstractVideoBuffer::WriteOnly 标志，则这会把映射内存当前内容坚持到视频帧。
另请参阅 map ().
返回视频帧的宽度。
Assigns the contents of other to a video frame.