avblocks-net

AVBlocks .NET SDK (CLI Samples)

Usage

Getting Started

Library Initialization

Before using any AVBlocks functionality, initialize the library:

using PrimoSoftware.AVBlocks;

Library.Initialize();

// Set license information. To run AVBlocks in demo mode, comment the next line out
// Library.SetLicense("<license-string>");

// Your code here

Library.Shutdown();

Core Concepts

MediaSocket

A MediaSocket represents an input or output media endpoint. It describes:

• The media file location (File property)
• The stream type (StreamType property)
• One or more media pins (Pins collection)

MediaSocket socket = new MediaSocket();
socket.File = "input.mp4";
socket.StreamType = StreamType.UncompressedVideo;

MediaPin

A MediaPin represents a single media stream (audio or video) within a MediaSocket. Each pin contains:

• Stream information (StreamInfo property) - describes the format and characteristics of the stream
• Stream configuration for encoding/decoding

Key Properties:

• StreamInfo - Contains detailed format information (VideoStreamInfo or AudioStreamInfo)

Example for video input:

MediaPin pin = new MediaPin();
VideoStreamInfo vsi = new VideoStreamInfo();
pin.StreamInfo = vsi;

vsi.StreamType = StreamType.UncompressedVideo;
vsi.FrameWidth = 176;
vsi.FrameHeight = 144;
vsi.ColorFormat = ColorFormat.YUV420;
vsi.FrameRate = 30.0;
vsi.ScanType = ScanType.Progressive;

socket.Pins.Add(pin);

MediaInfo

MediaInfo is used to extract metadata and stream information from media files without processing the content.

Key Features:

• Extract audio/video stream details
• Read file metadata (title, artist, album, etc.)
• No transcoding required

using (MediaInfo info = new MediaInfo())
{
    info.Inputs[0].File = "input.mp4";
    
    if (info.Open())
    {
        // Access stream information
        foreach (StreamInfo streamInfo in info.Outputs[0].Pins)
        {
            // Process stream info
        }
        
        // Access metadata
        foreach (var attr in info.Outputs[0].Metadata)
        {
            Console.WriteLine($"{attr.Name}: {attr.Value}");
        }
        
        info.Close();
    }
    else
    {
        // Handle error
        ErrorInfo error = info.Error;
    }
}

Common Operations

Media Information Extraction

Stream Information

using (MediaInfo info = new MediaInfo())
{
    info.Inputs[0].File = inputFile;
    
    if (info.Open())
    {
        // Iterate through streams
        for (int streamIndex = 0; streamIndex < info.Outputs[0].Pins.Count; streamIndex++)
        {
            StreamInfo si = info.Outputs[0].Pins[streamIndex].StreamInfo;
            
            if (si.MediaType == MediaType.Video)
            {
                VideoStreamInfo vsi = (VideoStreamInfo)si;
                Console.WriteLine($"Video: {vsi.FrameWidth}x{vsi.FrameHeight}");
            }
            else if (si.MediaType == MediaType.Audio)
            {
                AudioStreamInfo asi = (AudioStreamInfo)si;
                Console.WriteLine($"Audio: {asi.SampleRate}Hz, {asi.Channels} channels");
            }
        }
        
        info.Close();
    }
}

Metadata Extraction

using (MediaInfo info = new MediaInfo())
{
    info.Inputs[0].File = inputFile;
    
    if (info.Open())
    {
        foreach (var attr in info.Outputs[0].Metadata)
        {
            Console.WriteLine($"{attr.Name}: {attr.Value}");
        }
        info.Close();
    }
}

Video Encoding

Encode Raw YUV to H.264/AVC

// Create input socket for raw YUV
MediaSocket inSocket = new MediaSocket();
inSocket.StreamType = StreamType.UncompressedVideo;
inSocket.File = "input.yuv";

MediaPin inPin = new MediaPin();
VideoStreamInfo inVsi = new VideoStreamInfo();
inPin.StreamInfo = inVsi;

inVsi.StreamType = StreamType.UncompressedVideo;
inVsi.ScanType = ScanType.Progressive;
inVsi.FrameWidth = 176;
inVsi.FrameHeight = 144;
inVsi.ColorFormat = ColorFormat.YUV420;
inVsi.FrameRate = 30.0;

inSocket.Pins.Add(inPin);

// Create output socket for H.264
MediaSocket outSocket = new MediaSocket();
outSocket.File = "output.h264";
outSocket.StreamType = StreamType.H264;

MediaPin outPin = new MediaPin();
VideoStreamInfo outVsi = new VideoStreamInfo();
outPin.StreamInfo = outVsi;

outVsi.StreamType = StreamType.H264;
outVsi.FrameWidth = 176;
outVsi.FrameHeight = 144;
outVsi.FrameRate = 30.0;

outSocket.Pins.Add(outPin);

// Encode
using (Transcoder transcoder = new Transcoder())
{
    transcoder.Inputs.Add(inSocket);
    transcoder.Outputs.Add(outSocket);
    
    if (transcoder.Open())
    {
        if (transcoder.Run())
        {
            Console.WriteLine("Encoding successful");
        }
        transcoder.Close();
    }
}

Encode with Preset

MediaSocket inSocket = new MediaSocket();
inSocket.File = "input.yuv";
// ... configure input

MediaSocket outSocket = new MediaSocket();
outSocket.File = "output.mp4";
outSocket.Preset = Preset.Video.Generic.MP4.Base_H264_AAC;

using (Transcoder transcoder = new Transcoder())
{
    transcoder.Inputs.Add(inSocket);
    transcoder.Outputs.Add(outSocket);
    
    if (transcoder.Open())
    {
        transcoder.Run();
        transcoder.Close();
    }
}

Video Decoding

Decode H.264 to Raw YUV

// Create input socket for H.264
MediaSocket inSocket = new MediaSocket();
inSocket.File = "input.h264";
inSocket.StreamType = StreamType.H264;

// Create output socket for raw YUV
MediaSocket outSocket = new MediaSocket();
outSocket.File = "output.yuv";
outSocket.StreamType = StreamType.UncompressedVideo;

MediaPin outPin = new MediaPin();
VideoStreamInfo outVsi = new VideoStreamInfo();
outPin.StreamInfo = outVsi;

outVsi.StreamType = StreamType.UncompressedVideo;
outVsi.ColorFormat = ColorFormat.YUV420;

outSocket.Pins.Add(outPin);

// Decode
using (Transcoder transcoder = new Transcoder())
{
    transcoder.Inputs.Add(inSocket);
    transcoder.Outputs.Add(outSocket);
    
    if (transcoder.Open())
    {
        transcoder.Run();
        transcoder.Close();
    }
}

Audio Encoding

Encode WAV to AAC (ADTS)

MediaSocket inSocket = new MediaSocket();
inSocket.File = "input.wav";

MediaSocket outSocket = new MediaSocket();
outSocket.File = "output.aac";
outSocket.StreamType = StreamType.Aac;
outSocket.StreamSubType = StreamSubType.AacAdts;

using (Transcoder transcoder = new Transcoder())
{
    transcoder.Inputs.Add(inSocket);
    transcoder.Outputs.Add(outSocket);
    
    if (transcoder.Open())
    {
        transcoder.Run();
        transcoder.Close();
    }
}

Encode WAV to MP3

MediaSocket inSocket = new MediaSocket();
inSocket.File = "input.wav";

MediaSocket outSocket = new MediaSocket();
outSocket.File = "output.mp3";
outSocket.StreamType = StreamType.Mp3;

using (Transcoder transcoder = new Transcoder())
{
    transcoder.Inputs.Add(inSocket);
    transcoder.Outputs.Add(outSocket);
    
    if (transcoder.Open())
    {
        transcoder.Run();
        transcoder.Close();
    }
}

Container Operations

Demux MP4 File

// Extract video and audio streams from MP4
using (Transcoder transcoder = new Transcoder())
{
    // Input
    MediaSocket inSocket = new MediaSocket();
    inSocket.File = "input.mp4";
    transcoder.Inputs.Add(inSocket);
    
    // Output for video stream
    MediaSocket videoOut = new MediaSocket();
    videoOut.File = "video.mp4";
    videoOut.StreamType = StreamType.H264;
    transcoder.Outputs.Add(videoOut);
    
    // Output for audio stream
    MediaSocket audioOut = new MediaSocket();
    audioOut.File = "audio.mp4";
    audioOut.StreamType = StreamType.Aac;
    transcoder.Outputs.Add(audioOut);
    
    if (transcoder.Open())
    {
        transcoder.Run();
        transcoder.Close();
    }
}

Mux MP4 File

// Combine separate audio and video files into MP4 container
using (Transcoder transcoder = new Transcoder())
{
    // Video input
    MediaSocket videoIn = new MediaSocket();
    videoIn.File = "video.h264.mp4";
    transcoder.Inputs.Add(videoIn);
    
    // Audio input
    MediaSocket audioIn = new MediaSocket();
    audioIn.File = "audio.aac.mp4";
    transcoder.Inputs.Add(audioIn);
    
    // Combined output
    MediaSocket outSocket = new MediaSocket();
    outSocket.File = "output.mp4";
    transcoder.Outputs.Add(outSocket);
    
    if (transcoder.Open())
    {
        transcoder.Run();
        transcoder.Close();
    }
}

Error Handling

using (Transcoder transcoder = new Transcoder())
{
    transcoder.Inputs.Add(inSocket);
    transcoder.Outputs.Add(outSocket);
    
    if (!transcoder.Open())
    {
        PrintError("Open Transcoder", transcoder.Error);
        return false;
    }
    
    if (!transcoder.Run())
    {
        PrintError("Run Transcoder", transcoder.Error);
        transcoder.Close();
        return false;
    }
    
    transcoder.Close();
}

static void PrintError(string action, ErrorInfo error)
{
    if (error != null)
    {
        Console.WriteLine($"Error: {action}");
        Console.WriteLine($"  Code: {error.Code}");
        Console.WriteLine($"  Message: {error.Message}");
        Console.WriteLine($"  Hint: {error.Hint}");
    }
}

Available Samples

See samples/README.md for a complete list of working examples including:

• Media Info: Extract stream information and metadata
• Encoding: AAC, MP3, H.264/AVC, with presets
• Decoding: H.264 to YUV
• Container Operations: Demux/Mux MP4 files
• Misc: Re-encoding, slideshow generation

Development

macOS

Download AVBlocks .NET Core and Assets

See Download .NET Core and Assets on macOS

Setup

See Setup for macOS

Build

See Build on macOS

Run

See README in the samples subdirectory.

Linux

Download AVBlocks .NET Core and Assets

See Download .NET Core and Assets on Linux

Setup

See Setup for Linux

Build

See Build on Linux

Run

See README in the samples subdirectory.

Windows

Download AVBlocks .NET Core and Assets

See Download .NET Core and Assets on Windows

Setup

See Setup for Windows

Build

See Build on Windows

Run

See README in the samples subdirectory.

How to obtain Commercial License

See License Options for details.

We offer discounts for:

• Competitive product
• Startup
• Educational institution
• Open source project