The QVideoFrame class provides a representation of a frame of video data. 更多...
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 . A 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 | The frame is stored using a 16-bit BGR format (5-6-5). |
| QVideoFrame.Format_BGR555 | 13 | The frame is stored using a 16-bit BGR format (5-5-5). |
| 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 | Start value for user defined pixel formats. |
构造 null 视频帧。
Constructs a video frame from a buffer of the given pixel format and size in pixels.
注意： This doesn't increment the reference count of the video buffer.
Constructs a video frame of the given pixel format and size in pixels.
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 .
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。
对于 OpenGL 纹理，这将是纹理 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。
返回图像格式等效视频帧像素 format 。若没有等效格式 QImage.Format_Invalid is returned 代替。
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 () and QAbstractVideoBuffer.MapMode .
Identifies if the mapped contents of a video frame were read from the frame when it was mapped.
这是方便的校验函数若 MapMode contains the 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 () and 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.
这是方便的校验函数若 MapMode contains the QAbstractVideoBuffer.WriteOnly 标志。
Returns true if the video frame will be updated when unmapped, 和 false 否则。
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 () and QAbstractVideoBuffer.MapMode .
Maps the contents of a video frame to memory.
映射 mode indicates whether the contents of the mapped memory should be read from and/or written to the frame. If the map mode includes the 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.
While mapped the contents of a video frame can be accessed directly through the pointer returned by the 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 ().
Returns the mode a video frame was mapped to system memory in.
另请参阅 map () 和 QAbstractVideoBuffer.MapMode .
Returns the number of bytes occupied by the mapped frame data.
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。
Returns an video pixel format equivalent to an image format 。若没有等效格式 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 ().
释放映射内存，映射通过 map () 函数。
若 MapMode 包括 QAbstractVideoBuffer.WriteOnly flag this will persist the current content of the mapped memory to the video frame.
另请参阅 map ().
返回视频帧的宽度。
