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VideoFrame

Namespace: SpawnDev.SpawnJS.JSObjects
Inheritance: SpawnJSObject -> VideoFrame
Attribute: [Transferable]
MDN Reference: VideoFrame - MDN

The VideoFrame interface of the WebCodecs API represents a single frame of video. It can be created from various image sources and is transferable between workers without copying.

Constructors

Signature Description
VideoFrame(SpawnJSObjectReference _ref) Deserialization constructor.

Properties

Property Type Description
Format string? The pixel format (e.g., "I420", "NV12", "RGBA", "BGRA").
CodedWidth int Width of the frame including any non-visible padding.
CodedHeight int Height of the frame including any non-visible padding.
DisplayWidth int Width intended for display (after aspect ratio adjustment).
DisplayHeight int Height intended for display.
Duration long? Duration of the frame in microseconds.
Timestamp long Timestamp in microseconds.
ColorSpace SpawnJSObject The color space of the frame.

Methods

Method Return Type Description
CopyTo(ArrayBuffer destination) Task Copies frame data to a buffer.
Clone() VideoFrame Creates a copy of the frame.
Close() void Releases the frame's resources. Must be called when done.

Example

// Create a VideoFrame from an HTMLCanvasElement
using var canvas = JS.Get<HTMLCanvasElement>("document.getElementById('myCanvas')");
using var frame = new VideoFrame(canvas);

// Access frame dimensions and metadata
Console.WriteLine($"Display size: {frame.DisplayWidth}x{frame.DisplayHeight}");
Console.WriteLine($"Coded size: {frame.CodedWidth}x{frame.CodedHeight}");
Console.WriteLine($"Timestamp: {frame.Timestamp} microseconds");
Console.WriteLine($"Duration: {frame.Duration} microseconds");
Console.WriteLine($"Format: {frame.Format}");

// Get the allocation size needed to copy the frame data
int allocSize = frame.AllocationSize();
Console.WriteLine($"Allocation size: {allocSize} bytes");

// Copy frame pixel data to an ArrayBuffer
using var buffer = new ArrayBuffer(allocSize);
await frame.CopyTo(buffer);

// Clone the frame (creates a new reference to the same data)
using var clonedFrame = frame.Clone();
Console.WriteLine($"Cloned frame: {clonedFrame.DisplayWidth}x{clonedFrame.DisplayHeight}");

// Create a VideoFrame with explicit options (e.g., for setting timestamp)
using var frame2 = new VideoFrame(canvas, new VideoFrameOptions
{
    Timestamp = 33333, // 33.3ms into video
});

// Always close frames when done to release resources
frame.Close();
clonedFrame.Close();
frame2.Close();