WebM

Key takeaways

WebM belongs to computer science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect WebM to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of WebM from memory before moving on to harder problems.

Reference excerpt

WebM is an audiovisual media file format. It is primarily intended to offer a royalty-free alternative to use in HTML video and HTML audio elements. It has a sister project for images: WebP. The development of the format is sponsored by Google, and the corresponding software is distributed under a BSD license. WebM was a collaborative effort first released in 2010. The WebM container is based on a profile of Matroska. WebM initially supported VP8 video and Vorbis audio streams. In 2013, it was updated to accommodate VP9 video and Opus audio. It also supports the AV1 codec.

Vendor support

Software Native WebM support by Mozilla Firefox, Opera, and Google Chrome was announced at the 2010 Google I/O conference. Internet Explorer 9 requires third-party WebM software. In 2021, Apple released Safari 14.1 for macOS, which added native WebM support to the browser. As of 2019, QuickTime does not natively support WebM, but does with a suitable third-party plug-in. In 2011, the Google WebM Project Team released plugins for Internet Explorer and Safari to allow playback of WebM files through the standard HTML5 <video> tag. As of 9 June 2012, Internet Explorer 9 and later supported the plugin for Windows Vista and later. VLC media player, MPlayer, K-Multimedia Player and JRiver Media Center have native support for playing WebM files. FFmpeg can encode and decode VP8 videos when built with support for libvpx, the VP8/VP9 codec library of the WebM project, as well as mux/demux WebM-compliant files. On July 23, 2010 Fiona Glaser, Ronald Bultje, and David Conrad of the FFmpeg team announced the ffvp8 decoder. Their testing found that ffvp8 was faster than Google's own libvpx decoder. MKVToolNix, the popular Matroska creation tools, implemented support for multiplexing/demultiplexing WebM-compliant files out of the box. Haali Media Splitter also announced support for muxing/demuxing of WebM. Since version 1.4.9, the LiVES video editor has support for realtime decoding and for encoding to WebM format using ffmpeg libraries. MPC-HC since build SVN 2071 supports WebM playback with internal VP8 decoder based on FFmpeg's code. The full decoding support for WebM is available in MPC-HC since version 1.4.2499.0. Android is WebM-enabled since version 2.3 Gingerbread, which was first made available via the Nexus S smartphone and streamable since Android 4.0 Ice Cream Sandwich. The Microsoft Edge browser supports WebM since April 2016. On July 30, 2019, Blender 2.80 was released with WebM support. iOS did not natively play WebM until 2021, when support for WebM was added in Safari 15 as part of iOS 15. The Sony PlayStation 5 supports capturing 1080p and 2160p footage in WebM format. ChromeOS screen recordings are saved as WebM files.

Hardware WebM Project licenses VP8 hardware accelerators (RTL IP) to semiconductor companies for 1080p encoding and decoding at zero cost. AMD, ARM and Broadcom have announced support for hardware acceleration of the WebM format. Intel is also considering hardware-based acceleration for WebM in its Atom-based TV chips if the format gains popularity. Qualcomm and Texas Instruments have announced support, with native support coming to the TI OMAP processor. Chips&Media have announced a fully hardware decoder for VP8 that can decode full HD resolution (1080p) VP8 streams at 60 frames per second. Nvidia is supporting VP8 and provides both hardware decoding and encoding in the Tegra 4 and Tegra 4i SoCs. Nvidia announced 3D video support for WebM through HTML5 and their Nvidia 3D Vision technology. On January 7, 2011, Rockchip released the world's first chip to host a full hardware implementation of 1080p VP8 decoding. The video acceleration in the RK29xx chip is handled by the WebM Project's G-Series 1 hardware decoder IP. In June 2011, ZiiLABS demonstrated their 1080p VP8 decoder implementation running on the ZMS-20 processor. The chip's programmable media processing array is used to provide the VP8 acceleration. ST-Ericsson and Huawei also had hardware implementations in their computer chips.

Streaming capabilities Since 2017, Icecast — a streaming media server traditionally used for audio streaming — has supported live video streaming using the WebM format (VP8/VP9/AV1 video codecs with Vorbis/Opus audio codecs). This enables broadcasting of high-quality, royalty-free, open-standard video streams that can be played directly in browsers without requiring proprietary plugins or players. Archived streams and server listings demonstrate WebM's viability for live streaming over Icecast, including examples of 1080p VP9 streams. Current implementations include live streams accessible at https://rdst.win:59000/dos.webm, with server status visible at https://rdst.win:59000.

Streaming examples and resources webm.win — Demonstrates a live WebM stream via Icecast (VP9 video with Vorbis audio, playable in browsers using the HTML5 <video> element) and provides instructions for setting up similar broadcasting. (accessed 27 September 2025) Archived Icecast directory with WebM streams (June 2017) Archived WebM stream example (2017)

… excerpt ends here. Continue reading the full article.

Worked examples

Example 1 — a first encounter with WebM

Start with the simplest possible case. Write down what WebM claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In computer science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to WebM before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about WebM ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of WebM

In research: WebM appears in computer science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses WebM in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: WebM is common in secondary-school and first-year university syllabi. It links to neighbouring topics Computer-related introductions in 2010, Free digital container formats, Google, so understanding it makes those chapters shorter.
In everyday life: Look for WebM outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

How to study WebM in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what WebM means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain WebM out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is WebM in simple terms?

WebM is an audiovisual media file format. It is primarily intended to offer a royalty-free alternative to use in HTML video and HTML audio elements.

Why does WebM matter?

Because it connects several computer science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study WebM?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on WebM.