Bridge blocks¶

Media Blocks SDK .Net

Bridges can be used to link two pipelines and dynamically switch between them. For example, you can switch between different files or cameras in the first Pipeline without interrupting streaming in the second Pipeline.

To link source and sink, give them the same name. Each bridge pair has a unique channel name.

Bridge audio sink and source¶

Bridges can be used to connect different media pipelines and use them independently. BridgeAudioSourceBlock is used to connect to BridgeAudioSinkBlock and supports uncompressed audio.

Block info¶

BridgeAudioSourceBlock information¶

Pin direction	Media type	Pins count
Output audio	uncompressed audio	1

BridgeAudioSinkBlock information¶

Pin direction	Media type	Pins count
Input audio	uncompressed audio	1

Sample pipelines¶

First pipeline with an audio source and a bridge audio sink¶

graph LR;
    VirtualAudioSourceBlock-->BridgeAudioSinkBlock;

Second pipeline with a bridge audio source and an audio renderer¶

graph LR;
    BridgeAudioSourceBlock-->AudioRendererBlock;

Sample code¶

The source pipeline with virtual audio source and bridge audio sink.

// create source pipeline
var sourcePipeline = new MediaBlocksPipeline();

// create virtual audio source and bridge audio sink
var audioSourceBlock = new VirtualAudioSourceBlock(new VirtualAudioSourceSettings());
var bridgeAudioSink = new BridgeAudioSinkBlock(new BridgeAudioSinkSettings());

// connect source and sink
sourcePipeline.Connect(audioSourceBlock.Output, bridgeAudioSink.Input);

// start pipeline
await sourcePipeline.StartAsync();

The sink pipeline with bridge audio source and audio renderer.

// create sink pipeline
var sinkPipeline = new MediaBlocksPipeline();

// create bridge audio source and audio renderer
var bridgeAudioSource = new BridgeAudioSourceBlock(new BridgeAudioSourceSettings());
var audioRenderer = new AudioRendererBlock();

// connect source and sink
sinkPipeline.Connect(bridgeAudioSource.Output, audioRenderer.Input);

// start pipeline
await sinkPipeline.StartAsync();

Bridge video sink and source¶

Bridges can be used to connect different media pipelines and use them independently. BridgeVideoSinkBlock is used to connect to the BridgeVideoSourceBlock and supports uncompressed video.

Blocks info¶

BridgeVideoSinkBlock information¶

Pin direction	Media type	Pins count
Input video	uncompressed video	1

BridgeVideoSourceBlock information¶

Pin direction	Media type	Pins count
Output video	uncompressed video	1

Sample pipelines¶

First pipeline with a video source and a bridge video sink¶

graph LR;
    VirtualVideoSourceBlock-->BridgeVideoSinkBlock;

Second pipeline with a bridge video source and a video renderer¶

graph LR;
    BridgeVideoSourceBlock-->VideoRendererBlock;

Sample code¶

Source pipeline with a virtual video source and bridge video sink.

// create source pipeline
var sourcePipeline = new MediaBlocksPipeline();

// create virtual video source and bridge video sink
var videoSourceBlock = new VirtualVideoSourceBlock(new VirtualVideoSourceSettings());
var bridgeVideoSink = new BridgeVideoSinkBlock(new BridgeVideoSinkSettings());

// connect source and sink
sourcePipeline.Connect(videoSourceBlock.Output, bridgeVideoSink.Input);

// start pipeline
await sourcePipeline.StartAsync();

Sink pipeline with a bridge video source and video renderer.

// create sink pipeline
var sinkPipeline = new MediaBlocksPipeline();

// create bridge video source and video renderer
var bridgeVideoSource = new BridgeVideoSourceBlock(new BridgeVideoSourceSettings());
var videoRenderer = new VideoRendererBlock(sinkPipeline, VideoView1);

// connect source and sink
sinkPipeline.Connect(bridgeVideoSource.Output, videoRenderer.Input);

// start pipeline
await sinkPipeline.StartAsync();

Bridge subtitle sink and source¶

Bridges can be used to connect different media pipelines and use them independently. BridgeSubtitleSourceBlock is used to connect to the BridgeSubtitleSinkBlockand supports text media type.

Block info¶

BridgeSubtitleSourceBlock information¶

Pin direction	Media type	Pins count
Output video	text	1

BridgeSubtitleSinkBlock information¶

Pin direction	Media type	Pins count
Output video	text	1

Proxy source¶

Proxy source/proxy sink pair of blocks can be used to connect different media pipelines and use them independently.

Block info¶

Name: ProxySourceBlock.

Pin direction	Media type	Pins count
Output	Any uncompressed	1

Sample pipelines¶

First pipeline with a video source and a proxy video sink¶

graph LR;
    VirtualVideoSourceBlock-->ProxySinkBlock;

Second pipeline with a proxy video source and a video renderer¶

graph LR;
    ProxySourceBlock-->VideoRendererBlock;

Sample code¶

// source pipeline with virtual video source and proxy sink
var sourcePipeline = new MediaBlocksPipeline();
var videoSourceBlock = new VirtualVideoSourceBlock(new VirtualVideoSourceSettings());
var proxyVideoSink = new ProxySinkBlock();
sourcePipeline.Connect(videoSourceBlock.Output, proxyVideoSink.Input);

// sink pipeline with proxy video source and video renderer
var sinkPipeline = new MediaBlocksPipeline();
var proxyVideoSource = new ProxySourceBlock(proxyVideoSink);
var videoRenderer = new VideoRendererBlock(sinkPipeline, VideoView1);
sinkPipeline.Connect(proxyVideoSource.Output, videoRenderer.Input);

// start pipelines
await sourcePipeline.StartAsync();
await sinkPipeline.StartAsync();

Platforms¶

All bridge blocks are supported on Windows, macOS, Linux, iOS, and Android.

Bridge Buffer sink and source¶

BridgeBuffer blocks provide high-performance memory buffer-based communication between pipelines, ideal for sharing video frames without encoding overhead.

Block info¶

BridgeBufferSinkBlock information¶

Pin direction	Media type	Pins count
Input video	uncompressed video	1

BridgeBufferSourceBlock information¶

Pin direction	Media type	Pins count
Output	auto	1

Sample code¶

// First pipeline with video source and bridge buffer sink
var sourcePipeline = new MediaBlocksPipeline();
var videoSource = new SystemVideoSourceBlock(videoSettings);

var videoInfo = new VideoFrameInfoX(1920, 1080, VideoFormatX.NV12);
var bufferSink = new BridgeBufferSinkBlock("buffer-channel", videoInfo);
sourcePipeline.Connect(videoSource.Output, bufferSink.Input);

// Second pipeline with bridge buffer source and renderer
var sinkPipeline = new MediaBlocksPipeline();
var bufferSource = new BridgeBufferSourceBlock("buffer-channel");
var videoRenderer = new VideoRendererBlock(sinkPipeline, VideoView1);
sinkPipeline.Connect(bufferSource.Output, videoRenderer.Input);

await sourcePipeline.StartAsync();
await sinkPipeline.StartAsync();

InterPipe sink and source¶

InterPipe blocks use GStreamer's interpipesink/interpipesrc elements for efficient inter-pipeline communication with support for both audio and video.

Block info¶

InterPipeSinkBlock information¶

Pin direction	Media type	Pins count
Input	audio or video	1

InterPipeSourceBlock information¶

Pin direction	Media type	Pins count
Output	audio or video	1

Sample code¶

// First pipeline with video source and interpipe sink
var sourcePipeline = new MediaBlocksPipeline();
var videoSource = new SystemVideoSourceBlock(videoSettings);

var videoInfo = new VideoFrameInfoX(1920, 1080, VideoFormatX.NV12);
var interpipeSink = new InterPipeSinkBlock("interpipe-channel", videoInfo);
sourcePipeline.Connect(videoSource.Output, interpipeSink.Input);

// Second pipeline with interpipe source and renderer
var sinkPipeline = new MediaBlocksPipeline();
var interpipeSource = new InterPipeSourceBlock("interpipe-channel", MediaBlockPadMediaType.Video);
var videoRenderer = new VideoRendererBlock(sinkPipeline, VideoView1);
sinkPipeline.Connect(interpipeSource.Output, videoRenderer.Input);

await sourcePipeline.StartAsync();
await sinkPipeline.StartAsync();

RS Inter sink and source¶

RSInter blocks use the Rust-based GStreamer rsinter plugin for high-performance inter-pipeline communication.

Block info¶

RSInterSinkBlock information¶

Pin direction	Media type	Pins count
Input	audio or video	1

RSInterSourceBlock information¶

Pin direction	Media type	Pins count
Output	audio or video	1

Sample code¶

// First pipeline with video source and rsinter sink
var sourcePipeline = new MediaBlocksPipeline();
var videoSource = new SystemVideoSourceBlock(videoSettings);

var rsinterSink = new RSInterSinkBlock(MediaBlockPadMediaType.Video, "rsinter-channel");
sourcePipeline.Connect(videoSource.Output, rsinterSink.Input);

// Second pipeline with rsinter source and renderer
var sinkPipeline = new MediaBlocksPipeline();
var rsinterSource = new RSInterSourceBlock(MediaBlockPadMediaType.Video, "rsinter-channel");
var videoRenderer = new VideoRendererBlock(sinkPipeline, VideoView1);
sinkPipeline.Connect(rsinterSource.Output, videoRenderer.Input);

await sourcePipeline.StartAsync();
await sinkPipeline.StartAsync();

AppBridge Video and Audio¶

AppBridge blocks use GStreamer's appsink and appsrc elements to provide direct buffer transfer between pipelines with preserved timestamps. Unlike other bridge types that may regenerate timestamps, AppBridge maintains the original PTS (Presentation Timestamp), DTS (Decode Timestamp), and duration values.

This makes AppBridge ideal for:

Hardware outputs like Decklink cards that require precise timing synchronization
Live streaming scenarios where timestamp accuracy is critical
Multi-pipeline architectures where clock synchronization between pipelines is important

How it works¶

The sink block (AppBridgeVideoSinkBlock or AppBridgeAudioSinkBlock) captures buffers using appsink with sync=false to avoid clock-based delays
Buffers are passed directly to the linked source with their original timestamps preserved
The source block (AppBridgeVideoSourceBlock or AppBridgeAudioSourceBlock) injects buffers using appsrc with is-live=true and do-timestamp=false
The downstream element (e.g., Decklink) receives properly timestamped buffers for hardware clock synchronization

Block info¶

AppBridgeVideoSinkBlock¶

Pin direction	Media type	Pins count
Input	uncompressed video	1

AppBridgeVideoSourceBlock¶

Pin direction	Media type	Pins count
Output	uncompressed video	1

AppBridgeAudioSinkBlock¶

Pin direction	Media type	Pins count
Input	uncompressed audio	1

AppBridgeAudioSourceBlock¶

Pin direction	Media type	Pins count
Output	uncompressed audio	1

Settings¶

AppBridgeVideoSinkSettings / AppBridgeAudioSinkSettings¶

Property	Type	Default	Description
Channel	string	required	Unique channel name to match with source
Info	VideoFrameInfoX / AudioInfoX	required	Media format specification
MaxBuffers	int	5 (video) / 10 (audio)	Maximum buffer queue size
Sync	bool	false	Sync to pipeline clock (false for live sources)

AppBridgeVideoSourceSettings / AppBridgeAudioSourceSettings¶

Property	Type	Default	Description
Channel	string	required	Channel name matching the sink
Info	VideoFrameInfoX / AudioInfoX	required	Media format specification
IsLive	bool	true	Marks source as live for proper pipeline behavior
DoTimestamp	bool	false	Set to false to preserve original timestamps

Generating secure channel names¶

For security, use the GenerateUniqueChannel() helper method to create GUID-based channel names:

var channel = AppBridgeVideoSinkSettings.GenerateUniqueChannel("decklink_video");
// Returns: "decklink_video_a1b2c3d4e5f6..."

Sample pipelines¶

Main pipeline with video/audio tee and AppBridge sinks¶

graph LR;
    VideoSource-->VideoTee;
    VideoTee-->VideoRenderer;
    VideoTee-->AppBridgeVideoSinkBlock;
    AudioSource-->AudioTee;
    AudioTee-->AudioRenderer;
    AudioTee-->AppBridgeAudioSinkBlock;

Output pipeline with AppBridge sources and Decklink output¶

graph LR;
    AppBridgeVideoSourceBlock-->DecklinkVideoAudioSinkBlock;
    AppBridgeAudioSourceBlock-->VolumeBlock;
    VolumeBlock-->DecklinkVideoAudioSinkBlock;

Sample code¶

Complete example showing Decklink output using AppBridge for proper timestamp handling:

// Main pipeline with video/audio sources
var mainPipeline = new MediaBlocksPipeline();

// Video and audio format definitions
var videoInfo = new VideoFrameInfoX(1920, 1080, new VideoFrameRate(60));
var audioInfo = new AudioInfoX(AudioFormatX.S16LE, 48000, 2);

// Create tees for splitting streams
var videoTee = new TeeBlock(2, MediaBlockPadMediaType.Video);
var audioTee = new TeeBlock(2, MediaBlockPadMediaType.Audio);

// AppBridge sinks in main pipeline
var videoSinkSettings = new AppBridgeVideoSinkSettings("decklink_video", videoInfo);
var appBridgeVideoSink = new AppBridgeVideoSinkBlock(videoSinkSettings);

var audioSinkSettings = new AppBridgeAudioSinkSettings("decklink_audio", audioInfo);
var appBridgeAudioSink = new AppBridgeAudioSinkBlock(audioSinkSettings);

// Connect tee outputs to AppBridge sinks
mainPipeline.Connect(videoTee.Outputs[1], appBridgeVideoSink.Input);
mainPipeline.Connect(audioTee.Outputs[1], appBridgeAudioSink.Input);

// Decklink output pipeline
var decklinkPipeline = new MediaBlocksPipeline();

// AppBridge sources - same channel names as sinks
var videoSourceSettings = new AppBridgeVideoSourceSettings("decklink_video", videoInfo);
var appBridgeVideoSource = new AppBridgeVideoSourceBlock(videoSourceSettings);

var audioSourceSettings = new AppBridgeAudioSourceSettings("decklink_audio", audioInfo);
var appBridgeAudioSource = new AppBridgeAudioSourceBlock(audioSourceSettings);

// Decklink output
var decklinkVideoSettings = new DecklinkVideoSinkSettings(0, DecklinkMode.HD1080p60);
var decklinkAudioSettings = new DecklinkAudioSinkSettings(0);
var decklinkOutput = new DecklinkVideoAudioSinkBlock(decklinkVideoSettings, decklinkAudioSettings);

// Connect AppBridge sources to Decklink
decklinkPipeline.Connect(appBridgeVideoSource.Output, decklinkOutput.VideoInput);
decklinkPipeline.Connect(appBridgeAudioSource.Output, decklinkOutput.AudioInput);

// Start pipelines
await mainPipeline.StartAsync();
await decklinkPipeline.StartAsync();

// Cleanup when done
await decklinkPipeline.StopAsync();
appBridgeVideoSource.Dispose();
appBridgeAudioSource.Dispose();
appBridgeVideoSink.Dispose();
appBridgeAudioSink.Dispose();

When to use AppBridge vs other bridges¶

Bridge Type	Best For	Timestamp Handling
AppBridge	Decklink, hardware outputs, precise timing	Preserves original PTS/DTS
Standard Bridge	Software rendering, general use	May regenerate timestamps
InterPipe	Multiple consumers, flexible routing	Depends on configuration
RSInter	High-performance Rust-based	Depends on configuration
BridgeBuffer	Memory sharing, zero-copy	Buffer-based

Platforms¶

All bridge blocks are supported on Windows, macOS, Linux, iOS, and Android.

Note: InterPipe and RSInter blocks require the corresponding GStreamer plugins to be installed.