ImageDecoder.decode()
Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.
The decode()
method of the ImageDecoder
interface enqueues a control message to decode the frame of an image.
Syntax
ImageDecoder.decode(options)
Parameters
options
Optional-
An object containing the following members:
frameIndex
Optional-
An integer representing the index of the frame to decode. Defaults to
0
(the first frame). completeFramesOnly
Optional-
A
boolean
defaulting totrue
. Whenfalse
indicates that for progressive images the decoder may output an image with reduced detail.
Return Value
A promise
that resolves with an object containing the following members:
image
-
A
VideoFrame
containing the decoded image. complete
-
A
boolean
, iftrue
indicates thatimage
contains the final full-detail output.
Exceptions
If an error occurs, the promise will resolve with following exception:
InvalidStateError
DOMException
-
Returned if any of the following conditions apply:
close
is true, meaningclose()
has already been called.- The requested frame does not exist.
Examples
The following example decodes the second frame (at index 1
) and prints the resulting VideoFrame
to the console.
console.log(imageDecoder.decode({frameIndex: 1}));
Specifications
Specification |
---|
WebCodecs # dom-imagedecoder-decode |
Browser compatibility
BCD tables only load in the browser