Перейти к основному содержимому

MediaSource

The MediaSource class hierarchy provides an abstraction for different types of media content sources in Avalonia Accelerate MediaControls. This allows the media playback system to handle various content sources (files, URLs, streams) through a unified interface.

MediaSource (Abstract Base Class)​

MediaSource is an abstract base class that defines the common interface for all media sources.

Methods​

MethodReturn TypeDescription
Dispose()voidReleases resources used by the media source.

UriSource Class​

The UriSource class represents media content referenced by a URI, which can point to local files or network resources.

Properties​

PropertyTypeDescription
SourceUriGets the URI that points to the media content.

Constructors​

ConstructorDescription
UriSource(Uri source)Initializes with the specified URI.
UriSource(string source)Initializes with the specified URI string.

Methods​

MethodReturn TypeDescription
Equals(UriSource other)boolDetermines equality with another UriSource.
Equals(object obj)boolDetermines equality with an object.
GetHashCode()intReturns the hash code for this instance.
Dispose()voidReleases resources (typically a no-op).

Usage Examples​

// From a string URL
var webSource = new UriSource("https://example.com/video.mp4");

// From a file path
var fileSource = new UriSource("file:///C:/Videos/sample.mp4");

// From a Uri object
var uri = new Uri("rtsp://example.com/stream");
var streamSource = new UriSource(uri);

StreamSource Class​

The StreamSource class represents media content provided as a stream, allowing for dynamic or in-memory content to be played.

Properties​

PropertyTypeDescription
TargetStreamStreamGets the underlying stream containing media data.
IsSeekableboolGets whether the underlying stream supports seeking.

Constructors​

ConstructorDescription
StreamSource(Stream targetStream)Initializes with the specified stream.

Methods​

MethodReturn TypeDescription
Equals(StreamSource other)boolDetermines equality with another StreamSource.
Dispose()voidReleases resources, including the underlying stream.

Usage Examples​

// From a file stream
var fileStream = File.OpenRead("video.mp4");
var fileStreamSource = new StreamSource(fileStream);

// From a memory stream
byte[] videoData = GetVideoData();
var memoryStream = new MemoryStream(videoData);
var memoryStreamSource = new StreamSource(memoryStream);

// From a network stream
var webRequest = WebRequest.Create("https://example.com/video.mp4");
var responseStream = webRequest.GetResponse().GetResponseStream();
var networkStreamSource = new StreamSource(responseStream);

Choosing Between UriSource and StreamSource​

When to Use UriSource​

  • Local media files.
  • Network streams with direct URLs.
  • Real-time protocol streams (RTSP/RTMP/RDP).
  • Any media with a standard URI representation.

Advantages:

  • Lower overhead.
  • Native handling by media backends.
  • No memory or lifetime management concerns.

When to Use StreamSource​

  • In-memory media content.
  • Dynamic content generated at runtime.
  • Content loaded from non-standard sources.
  • Content that needs preprocessing before playback.

Advantages:

  • Flexibility for custom content sources.
  • No need for temporary files.
  • Works with encrypted or protected content.

Resource Management​

Both UriSource and StreamSource implement IDisposable:

  • For UriSource, the Dispose method is typically a no-op.
  • For StreamSource, the Dispose method disposes the underlying stream.

The MediaPlayer manages the lifecycle automatically:

  • When setting a new Source, the previous Source is disposed.
  • When the player is released or uninitiated, the current Source is disposed.

Best Practices​

  1. Resource Management:

    • Don't dispose streams passed to a StreamSource as it takes ownership.

  2. Source Selection:

    • Use UriSource for file and network media when possible (more efficient).
    • Use StreamSource for in-memory content or preprocessing.

  3. Error Handling:

    • Validate URIs before creating a UriSource
    • Verify streams are readable before creating a StreamSource
    • Handle exceptions when opening files or network resources

  4. Seeking Considerations:

    • Check StreamSource.IsSeekable to determine if seeking is supported.
    • If seeking is required, ensure the stream supports it (CanSeek = true).