ORTC SVC SimulCast
5 likes2,105 views
This document discusses ORTC SimulCast and how it differs from WebRTC 1.0. It explains that ORTC is WebRTC 1.0 plus SimulCast and multi-stream interoperability. It then defines SimulCast and describes AVC and SVC SimulCast approaches. It provides details on SVC including base layers, enhancement layers, parameters like temporal, spatial and quality layers. The document also outlines the changes in the ORTC API compared to the previous PeerConnection API and provides an overview of the new classes-based architecture. It notes that WebRTC NV will merge aspects of ORTC and ends by providing additional resources.
![SVC
21
var encodings = [
{
// 低解像度ベースレイヤ(1/2 フレームレート 1/2 解像度)
encodingId: "0",
resolutionScale: 2.0,
framerateScale: 2.0
},
{
// 拡張解像度ベースレイヤ(1/2 フレームレート 1/1 解像度)
encodingId: "E0",
resolutionScale: 1.0,
framerateScale: 2.0
},
{
// 低解像度ベースへの拡張レイヤ (1/1 レート, 1/2 解像度)
encodingId: "1",
dependencyEncodingIds: ["0"],
resolutionScale: 2.0,
framerateScale: 1.0
},
{
// 拡張解像度ベースへの拡張レイヤ (1/1 レート, 1/1 解像度)
encodingId: "E1",
dependencyEncodingIds: ["E0"],
resolutionScale: 1.0,
framerateScale: 1.0
}
];](https://image.slidesharecdn.com/ortcsimulcast-150927115855-lva1-app6891/85/ORTC-SVC-SimulCast-21-320.jpg)
ORTC SVC SimulCast
- 2. ● id: Jxck ● github: Jxck ● twitter: @jxck_ ● about: http://jxck.io ● blog: http://jxck.hatenablog.com ● podcast: http://mozaic.fm ● Love: music Jack
- 3. Q: Why ORTC ? A: long story... 3
- 4. 4 that’s all thank you !!
- 5. ORTC ≒ WebRTC 1.0 + SimulCast + MultiStream interop 5
- 6. Simulcast 6
- 8. AVC Simulcast 8 ● re-encoding for each client capability, network ○ heavy resource ○ latecy at server
- 9. SVC Simulcast 9 ● SVC encode at client ○ multi layered video ○ router choose a layer
- 10. SVC 10
- 11. SVC(scalable video coding) 11 ● multi layered coding ○ 1-base layer ○ n-enhancement layer ● parameter ○ Temporal (frame rate) ○ Spatial (resolution) ○ Quality (SNR)
- 12. Temporal 12
- 13. Spatial 13
- 14. Quality 14
- 15. layer ● base layer ○ lowest quality for video conference ○ small size ○ error correction ● enhancement layer ○ merge with base layer ○ more size ○ fallback to base layer if lost ● layer choice ○ layer routing server choice ○ negotiation, bandwidth estimation etc 15
- 16. ORTC API 16
- 17. Over View 17
- 18. before / after PeerConnection 18 // before let peer = new PeerConnection(); // call these during singalling peer.addStream(); peer.onnegotiationneeded; peer.createOffer/Answer(); peer.setLocal/RemoteDescription(); peer.onicecandidate; peer.addIceCandidate(); // ALL API are on PeerConnection Class
- 19. before / after PeerConnection 19 // after let iceGatherer = new RTCIceGatherer(iceGatherOptions); let iceTransport = new RTCIceTransport(iceGatherer); let dtlsTransport = new RTCDtlsTransport(iceTransport); let rtpSender = new RTCRtpSender(mediaStreamTrack, dtlsTransport); let rtpReceiver = new RTCRtpReceiver(dtlsTransport); let sendCapas = RTCRtpSender.getCapabilities('video'); let recvCapas = RTCRtpReceiver.getCapabilities('video'); // exchange caps // ALL API are on each Classes
- 20. before / after DataChannel 20 // after let iceGatherer = new RTCIceGatherer(iceGatherOptions); let iceTransport = new RTCIceTransport(iceGatherer); let dtlsTransport = new RTCDtlsTransport(iceTransport); let sctpTransport = new RTCSctpTransport(dtlsTransport); let channel = new RTCDataChannel(sctpTransport); // before peerConnection.createDataChannel((channel) => { });
- 21. SVC 21 var encodings = [ { // 低解像度ベースレイヤ(1/2 フレームレート 1/2 解像度) encodingId: "0", resolutionScale: 2.0, framerateScale: 2.0 }, { // 拡張解像度ベースレイヤ(1/2 フレームレート 1/1 解像度) encodingId: "E0", resolutionScale: 1.0, framerateScale: 2.0 }, { // 低解像度ベースへの拡張レイヤ (1/1 レート, 1/2 解像度) encodingId: "1", dependencyEncodingIds: ["0"], resolutionScale: 2.0, framerateScale: 1.0 }, { // 拡張解像度ベースへの拡張レイヤ (1/1 レート, 1/1 解像度) encodingId: "E1", dependencyEncodingIds: ["E0"], resolutionScale: 1.0, framerateScale: 1.0 } ];
- 22. complicated ? 22 classes based on protocol stack http://www.slideshare.net/iwashi86/20140801-web-rtcmeetup3r3
- 25. have a nice web :) 25
- 26. Jack