ReadMe.md

PGS4NET

Introduction

The purpose of this library is to someday facilitate intuitive interaction with Presentation Graphics Stream (PGS) subtitles, often times referred to as SUP subtitles due to their file extension.

In its current, early state, it supports reading and writing both display sets and segments. Epoch composition is not yet implemented.

Examples

Display Sets

Reading display sets is illustrated below as seen in the PGS4NET.Examples.DisplaySetDump project:

using PGS4NET.DisplaySets;

if (args.Length != 1)
    throw new ArgumentException("A single parameter with a PGS file must be passed.");

using var stream = new FileStream(args[0], FileMode.Open);

while (stream.ReadDisplaySet() is DisplaySet displaySet)
{
    Console.WriteLine($"Read display set with PTS = {displaySet.Pts}");
}

Display sets can be written out to streams via the WriteDisplaySet extension method on the System.IO.Stream class.

Segments

Reading segments is illustrated below as seen in the PGS4NET.Examples.SegmentDump project:

using PGS4NET.Segments;

if (args.Length != 1)
    throw new ArgumentException("A single parameter with a PGS file must be passed.");

using var stream = new FileStream(args[0], FileMode.Open);

while (stream.ReadSegment() is Segment segment)
{
    switch (segment)
    {
        case PresentationCompositionSegment:
            Console.WriteLine("PCS");
            break;
        case WindowDefinitionSegment:
            Console.WriteLine("WDS");
            break;
        case PaletteDefinitionSegment:
            Console.WriteLine("PDS");
            break;
        case SingleObjectDefinitionSegment:
            Console.WriteLine("S-ODS");
            break;
        case InitialObjectDefinitionSegment:
            Console.WriteLine("I-ODS");
            break;
        case MiddleObjectDefinitionSegment:
            Console.WriteLine("M-ODS");
            break;
        case FinalObjectDefinitionSegment:
            Console.WriteLine("F-ODS");
            break;
        case EndSegment:
            Console.WriteLine("ES");
            break;
        default:
            throw new InvalidOperationException("Segment is of unhandled type.");
    }
}

Segments can be written out to streams via the WriteSegment extension method on the System.IO.Stream class.