https://github.com/lostbeard/webmparser
.Net WebM parser and editor. Supports duration fixing.
https://github.com/lostbeard/webmparser
csharp dotnet webm
Last synced: 28 days ago
JSON representation
.Net WebM parser and editor. Supports duration fixing.
- Host: GitHub
- URL: https://github.com/lostbeard/webmparser
- Owner: LostBeard
- License: mit
- Created: 2024-01-06T22:14:07.000Z (almost 2 years ago)
- Default Branch: main
- Last Pushed: 2024-01-09T02:56:08.000Z (over 1 year ago)
- Last Synced: 2025-03-07T16:52:01.632Z (7 months ago)
- Topics: csharp, dotnet, webm
- Language: C#
- Homepage:
- Size: 66.4 KB
- Stars: 1
- Watchers: 1
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE.txt
Awesome Lists containing this project
README
# SpawnDev.WebMParser
| Name | Package | Description |
|---------|-------------|-------------|
|**[SpawnDev.WebMParser](#webmparser)**|[](https://www.nuget.org/packages/SpawnDev.WebMParser)| .Net WebM parser and editor |
WebMParser is a .Net WebM parser written in C#.
The initial goal of this library is to allow adding a duration to WebM video files recorded using [MediaRecorder](https://developer.mozilla.org/en-US/docs/Web/API/MediaRecorder) in a web browser. I am using this library in a browser based Blazor WebAssembly video messaging application.
The demo project included with the library is a .Net core 8 console app that currently just allows testing the library.
To fix the duration in a WebM file, WebM parser reads the Timecode information from Clusters and SimpleBlocks and adds a Segment > Info > Duration element with the new duration.
Example of how to add Duration info if not found in a the WebM stream.
```cs
using var inputStream = new FileStream(inputFile, FileMode.Open, FileAccess.Read, FileShare.Read);
var webm = new WebMStreamParser(inputStream);
// FixDuration returns true if the WebM was modified
var modified = webm.FixDuration();
// webm.Modified will also be true if the WebM is modified
if (modified)
{
var outFile = Path.Combine(Path.GetDirectoryName(inputFile)!, Path.GetFileNameWithoutExtension(inputFile) + ".fixed" + Path.GetExtension(inputFile));
using var outputStream = new FileStream(outFile, FileMode.Create, FileAccess.Write, FileShare.None);
webm.CopyTo(outputStream);
}
```
Example that prints out basic info for every element found in the WebM stream
```cs
var elements = webm.Descendants;
foreach (var element in elements)
{
var indent = new string('-', element.IdChain.Length - 1);
Console.WriteLine($"{indent}{element}");
}
```
Example of how to get an element
```cs
var durationElement = webm.GetElement(ElementId.Segment, ElementId.Info, ElementId.Duration);
var duration = durationElement?.Data ?? 0;
```
Example of how to get all elements of a type
```cs
var segments = webm.GetElements(ElementId.Segment);
```
Example of how to use ElementIds to walk the data tree and access information
```cs
var segments = webm.GetContainers(ElementId.Segment);
foreach (var segment in segments)
{
var clusters = segment.GetContainers(ElementId.Cluster);
foreach (var cluster in clusters)
{
var timecode = cluster.GetElement(ElementId.Timecode);
if (timecode != null)
{
duration = timecode.Data;
};
var simpleBlocks = cluster.GetElements(ElementId.SimpleBlock);
var simpleBlockLast = simpleBlocks.LastOrDefault();
if (simpleBlockLast != null)
{
duration += simpleBlockLast.Timecode;
}
}
}
```
Example of how to add an element
All parent containers are automatically marked Modified if any children are added, removed, or changed.
```cs
var info = GetContainer(ElementId.Segment, ElementId.Info);
info!.Add(ElementId.Duration, 100000);
```