Class

WebMOutputFormat

WebM file format, based on Matroska.

Supports writing transparent video. For a video track to be marked as transparent, the first packet added must contain alpha side data.

Extends: MkvOutputFormat

Constructor

constructor(
	options?: MkvOutputFormatOptions,
): WebMOutputFormat;

Creates a new WebMOutputFormat configured with the specified options.

See MkvOutputFormatOptions.

Properties

fileExtension

get fileExtension(): string;

The file extension used by this output format, beginning with a dot.

mimeType

get mimeType(): string;

The base MIME type of the output format.

negativeTimestampSupport

get negativeTimestampSupport(): 'prefer-non-negative';

The degree to which this output format supports writing media data with negative timestamps.

• 'full' - Negative timestamps are fully supported.
• 'prefer-non-negative' - Negative timestamps are technically supported, but their use is discouraged.
• 'none' - Negative timestamps are not supported.
• null - Not applicable since the container doesn't support timestamped media at all.

supportsTimestampedMediaData

get supportsTimestampedMediaData(): boolean;

Whether this output format's tracks store timestamped media data. When true, the timestamps of added packets will be respected, allowing things like gaps in media data or non-zero start times. When false, the format's media data implicitly starts at zero and follows an implicit sequential timing from there, using the intrinsic durations of the media data.

supportsVideoTransformationMetadata

get supportsVideoTransformationMetadata(): boolean;

Whether this output format supports video rotation and flip metadata.

Methods

getSupportedCodecs()

getSupportedCodecs(): MediaCodec[];

Returns a list of media codecs that this output format can contain.

See MediaCodec.

getSupportedTrackCounts()

getSupportedTrackCounts(): TrackCountLimits;

Returns the number of tracks that this output format supports.

See TrackCountLimits.