From 36d22d82aa202bb199967e9512281e9a53db42c9 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 21:33:14 +0200 Subject: Adding upstream version 115.7.0esr. Signed-off-by: Daniel Baumann --- third_party/libwebrtc/docs/faq.md | 243 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 243 insertions(+) create mode 100644 third_party/libwebrtc/docs/faq.md (limited to 'third_party/libwebrtc/docs/faq.md') diff --git a/third_party/libwebrtc/docs/faq.md b/third_party/libwebrtc/docs/faq.md new file mode 100644 index 0000000000..439e9b3e1b --- /dev/null +++ b/third_party/libwebrtc/docs/faq.md @@ -0,0 +1,243 @@ +# FAQ + +### What is WebRTC? + +WebRTC is an open framework for the web that enables Real Time Communications +in the browser. It includes the fundamental building blocks for high-quality +communications on the web, such as network, audio and video components used in +voice and video chat applications. + +These components, when implemented in a browser, can be accessed through a +JavaScript API, enabling developers to easily implement their own RTC web app. + +The WebRTC effort is being standardized on an API level at the W3C and at the +protocol level at the IETF. + + +### Why should I use WebRTC? + +We think you'll want to build your next video-chat style application using +WebRTC. Here's why: + + * A key factor in the success of the web is that its core technologies -- + such as HTML, HTTP, and TCP/IP -- are open and freely implementable. + Currently, there is no free, high-quality, complete solution available + that enables communication in the browser. WebRTC enables this. + + * Already integrated with best-of-breed voice and video engines that have + been deployed on millions of endpoints over the last 8+ years. Google does + not charge royalties for WebRTC. + + * Includes and abstracts key NAT and firewall traversal technology, using + STUN, ICE, TURN, RTP-over-TCP and support for proxies. + + * Builds on the strength of the web browser: WebRTC abstracts signaling by + offering a signaling state machine that maps directly to `PeerConnection`. + Web developers can therefore choose the protocol of choice for their usage + scenario (for example, but not limited to, SIP, XMPP/Jingle, et al.). + + +### What is the Opus audio codec? + +[Opus][opus-link] is a royalty-free audio codec defined by IETF +RFC 6176. It supports constant and variable bitrate encoding from 6 kbit/s to +510 kbit/s, frame sizes from 2.5 ms to 60 ms, and various sampling rates from +8 kHz (with 4 kHz bandwidth) to 48 kHz (with 20 kHz bandwidth, where the +entire hearing range of the human auditory system can be reproduced). + +[opus-link]: http://opus-codec.org/ + +### What is the iSAC audio codec? + +iSAC is a robust, bandwidth-adaptive, wideband and super-wideband voice codec +developed by Global IP Solutions, and is used in many Voice over IP (VoIP) and +streaming audio applications. iSAC is used by industry leaders in hundreds of +millions of VoIP endpoints. This codec is included as part of the WebRTC +project. + + +### What is the iLBC audio codec? + +iLBC is a free narrowband voice codec that was developed by Global IP +Solutions, and is used in many Voice over IP (VoIP) and streaming audio +applications. In 2004, the final IETF RFC versions of the iLBC codec +specification and the iLBC RTP Profile draft became available. This codec is +included as part of the WebRTC project. + + +### What is the VP8 video codec? + +VP8 is a highly-efficient video compression technology developed by the WebM Project. It is the video codec included with WebRTC. + +### What is the VP9 video codec? + +Similar to VP8, VP9 is also from the WebM Project. Its a next-generation open video codec. From Chrome 48 on desktop and Android, VP9 will be an optional video codec for video calls. More details in [Google Developers][vp9-link]. + +[vp9-link]: https://developers.google.com/web/updates/2016/01/vp9-webrtc/ + +### What other components are included in the WebRTC package? + +#### Audio + +WebRTC offers a complete stack for voice communications. It includes not only +the necessary codecs, but other components necessary to great user +experiences. This includes software-based acoustic echo cancellation (AEC), +automatic gain control (AGC), noise reduction, noise suppression, and +hardware access and control across multiple platforms. + + +#### Video + +The WebRTC project builds on the VP8 codec, introduced in 2010 as part of the +[WebM Project][webm-link]. It includes components to conceal +packet loss and clean up noisy images, as well as capture and playback +capabilities across multiple platforms. + +[webm-link]: http://www.webmproject.org/ + +#### Network + +Dynamic jitter buffers and error concealment techniques are included for audio +and video, which help mitigate the effects of packet loss and unreliable +networks. Also included are components for establishing a peer-to-peer +connection using ICE / STUN / Turn / RTP-over-TCP and support for proxies. + + +### How do I access the WebRTC code? + +Go to [https://webrtc.googlesource.com/src][webrtc-repo-link]. + +[webrtc-repo-link]: https://webrtc.googlesource.com/src + + +### How can I test the quality of WebRTC components? + +We have put sample applications [here][examples-link]. + +[examples-link]: https://webrtc.googlesource.com/src/+/main/docs/native-code/development/index.md#example-applications + + +### Are WebRTC components subject to change? + +WebRTC is based on a API that is still under development through efforts at +WHATWG, W3C and IETF. We hope to get to a stable API once a few browser +vendors have implementations ready for testing. Once the API is stable, our +goal will be to offer backwards compatibility and interoperability. The WebRTC +API layer will be our main focus for stability and interoperability. The +components under it may be modified to improve quality, performance and +feature set. + + +### WebRTC components are open-source. How do I get the source and contribute code? + +Please see [Getting Started][getting-started-link] and +[Contributing bug fixes][contributing-link] for more information. + +[getting-started-link]: https://webrtc.googlesource.com/src/+/main/docs/native-code/development/index.md +[contributing-link]: https://webrtc.org/support/contributing + + +### To be a Contributor, do I need to sign any agreements? + +Yes, each Contributor must sign and return the +[Contributor License Agreement][cla-link] + +[cla-link]: https://developers.google.com/open-source/cla/individual?hl=en + +### How can I become a WebRTC committer? + +The process of becoming a committer is documented in a +[separate page][become-a-committer]. + +[become-a-committer]: https://webrtc.googlesource.com/src/+/refs/heads/main/g3doc/become_a_committer.md + +### Do I have to be a programmer to use WebRTC? + +Yes, to build WebRTC support into a software application or contribute +improvements, programming skills are required. However, usage of the +JavaScript APIs that call WebRTC in the browsers will only require typical web +development skills. + + +### Is the WebRTC project owned by Google or is it independent? + +WebRTC is an open-source project supported by Google, Mozilla and Opera. The +API and underlying protocols are being developed jointly at the W3C and IETF. + + +### Are the WebRTC components from Google's acquisition of Global IP Solutions? + +Yes. Some components, such as VoiceEngine, VideoEngine, NetEQ, AEC, et al. all +stem from the GIPS acquisition. + + +### What codecs are supported in WebRTC? + +The currently supported voice codecs are G.711, G.722, iLBC, and iSAC, and VP8 +is the supported video codec. The list of supported codecs may change in the +future. + + +### Please explain how WebRTC is free of charge? + +Some software frameworks, voice and video codecs require end-users, +distributors and manufacturers to pay patent royalties to use the intellectual +property within the software technology and/or codec. Google is not charging +royalties for WebRTC and its components including the codecs it supports (VP8 +for video and iSAC and iLBC for audio). For more information, see the [License +page][license-link]. + +[license-link]: https://webrtc.googlesource.com/src/+/main/LICENSE + + +### What does this license let me do? + +Like most BSD licenses, this license allows you to use the WebRTC code with a +minimum of restrictions on your use. You can use the code in proprietary +software as well as open source software. + + +### Do I need to release the source if I make changes? + +No, the license does not require you to release source if you make changes. +However, we would love to see any changes you make and possibly incorporate +them, so if you want to participate please visit the +[code review page][code-review-link] and submit some patches. + +[code-review-link]: https://webrtc-review.googlesource.com/ + + +### Why is there a separate patent grant? + +In order to decouple patents from copyright, thus preserving the pure BSD +nature of the copyright license, the license and the patent grant are +separate. This means we are using a standard (BSD) open source copyright +license, and the patent grant can exist on its own. This makes WebRTC +compatible with all major license scenarios. + + +### What if someone gets the code from Google and gives it to me without changes. Do I have a patent grant from Google? + +Yes, you still have the right to redistribute and you still have a patent +license for Google's patents that cover the code that Google released. + + +### What if someone makes a change to the code and gives it to me. Do I have a patent license from Google for that change? + +You still have the right to redistribute but no patent license for the changes +(if there are any patents covering it). We can't give patent licenses for +changes people make after we distribute the code, as we have no way to predict +what those changes will be. Other common licenses take the same approach, +including the Apache license. + + +### What if Google receives or buys a patent that covers the code I receive sometime after I receive the code. Do I have a patent grant for that patent? + +Yes, you still have the right to redistribute and you still have a patent +license for Google's patents that cover the code that Google released. + + +### What if my competitor uses the code and brings patent litigation against me for something unrelated to the code. Do they still have a patent license? + +Yes, they still have the right to redistribute and they still have a patent +license for Google's patents that cover the code that Google released. -- cgit v1.2.3