VideoFrame: allocationSize() method
Limited availability
This feature is not Baseline because it does not work in some of the most widely-used browsers.
Note: This feature is available in Dedicated Web Workers.
The allocationSize()
method of the VideoFrame
interface returns the number of bytes required to hold the video as filtered by options passed into the method.
Syntax
allocationSize()
allocationSize(options)
Parameters
options
Optional-
An object containing the following:
rect
Optional-
The rectangle of pixels to copy from the
VideoFrame
. If unspecified thevisibleRect
will be used. This is in the format of a dictionary object containing:x
: The x-coordinate.y
: The y-coordinate.width
: The width of the frame.height
: The height of the frame.
layout
Optional-
A list containing the following values for each plane in the
VideoFrame
. Planes may not overlap. If unspecified the planes will be tightly packed: format
Optional-
A pixel format for the pixel data in the
destination
. Can be set to"RGBA"
,"RGBX"
,"BGRA"
,"BGRX"
. If unspecified, theformat
will be used. colorSpace
Optional-
Specifies the color space of the pixel data in the
destination
. Can be set to"srgb"
for the sRGB color space or"display-p3"
for the display-p3 color space. Only applicable for RGB pixel formats. If unspecified,"srgb
will be used.
Return value
An integer containing the number of bytes needed to hold the frame as specified by options
.
Examples
In the following example the allocationSize
is returned for the rectangle at top left with dimensions of 800 by 600.
const videoRect = {
x: 0,
y: 0,
width: 800,
height: 600,
};
let size = VideoFrame.allocationSize({ rect: videoRect });
Specifications
Specification |
---|
WebCodecs # dom-videoframe-allocationsize |
Browser compatibility
BCD tables only load in the browser