State of the art lossy codecs and surround formats 2014-09-18 10:53:32 I thought I'd share these for interest. It's amazing how much is happening in the audio world right now.In terms of new-ish lossy codecs and surround formats, I know of the following - anyone know of any others?My explanations, where included, are from my current understanding - reality may be more complex OpusI don't need to explain this one. http://opus-codec.org/http://en.wikipedia.org/wiki/Opus_(audio_format)http://www.hydrogenaud.io/forums/index.php?showtopic=106911etcxHE-AACThis includes some information about Extended HE-AAC - see slide 15 onwards:http://www.irt.de/webarchiv/showdoc.php?z=...DA1MjE2I3BkZg==There are some xHE-AAC and Opus samples here:http://www.indexcom.com/streaming/codec/They're not mine, and I don't know what software versions were used to encode them.The Beatles sample is particularly challenging at low bitrates with its (uncomfortably) wide stereo.There are some very low bitrate examples in this demo video:http://www.drm.org/?page_id=2396(click "DRM-xHE-AAC demo")doc.php?z=NjI4MSMxMDA1MjE2I3BkZg==Dolby AC-4Dolby's latest codec, aiming to reduce the required bitrate compared to E-AC-3.A few details, and a link to the spec, here:http://www.investincotedazur.com/en/info/n...codec-standard/MPEG-H Part 3: AudioA new 3D audio standard, supporting a mixture of channel-based (like conventional 5.1), object-based (mono source + position information), and scene based (Higher Order Ambisonics) audio sources, efficient encoding of them, and a renderer to put it all back together and feed it to whatever speaker array (or headphones) you have.They are targeting 256kbs - 1.2Mbps in the first phase (effectively complete - standard will be published February 2015). It delivers close to "true transparency" at 1.2Mbps 22.2 channels:http://multimediacommunication.blogspot.co...th-meeting.htmlThey are targeting 48kbps - 128kbps in the second phase. It delivers "Good" quality (MUSHRA scale) at 128kbps for 22.2 channels:http://mpeg.chiariglione.org/meetings/109(see press release).Dolby Atmos HomeFrom the horse's mouth:http://blog.dolby.com/2014/06/dolby-atmos-...tions-answered/http://blog.dolby.com/2014/06/dolby-atmos-...ving-room-near/ECMA-407This seems to be a way of parametrically encoding multiple (e.g. 22.2) channels, using an extremely low bitrate addition to a standard lossy codec (e.g. AAC). There is a 22.2 demonstration running at 256kbps (using AAC).The spec is here:http://www.ecma-international.org/publicat...ds/Ecma-407.htmThe company behind it is here:http://www.swissaudec.com/Cheers,David.