# Reading MediaRecorder's webm/opus output

DevFeed: [Reading MediaRecorder's webm/opus output](<https://devfeed.tech/articles/reading-mediarecorder-s-webm-opus-output-35451.md>)

Original publisher: [Read original article](<https://darkcoding.net/software/reading-mediarecorders-webm-opus-output/>)

Author: Graham King

Published: 2018-07-27T19:34:18Z

Content type: tutorial

Language: en

Sources: [Graham King](<https://devfeed.tech/sources/graham-king.md>)

Topics: [JavaScript](<https://devfeed.tech/topics/javascript.md>), [file](<https://devfeed.tech/topics/file.md>), [Web Development](<https://devfeed.tech/topics/web-development.md>)

Tags: [audio](<https://devfeed.tech/tags/audio.md>), [chrome](<https://devfeed.tech/tags/chrome.md>), [codec](<https://devfeed.tech/tags/codec.md>), [container](<https://devfeed.tech/tags/container.md>), [ebml](<https://devfeed.tech/tags/ebml.md>), [javascript](<https://devfeed.tech/tags/javascript.md>), [python](<https://devfeed.tech/tags/python.md>), [software](<https://devfeed.tech/tags/software.md>), [webm](<https://devfeed.tech/tags/webm.md>)

## AI overview

A tutorial on inspecting MediaRecorder's audio/webm;codecs=opus output. It explains the WebM container, its relationship to Matroska and EBML, and how EBML elements encode IDs, lengths, and values using a hex editor and Python REPL.

## Source excerpt

Making like Theseus in the WEBM/MATROSKA/EBML audio maze