Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
Dear colleagues... I take the opportunity to inform you about recent work at the MPEG, presenting updates and (by documents backed) official information. 1. http://www.itu.int/net/pressoffice/press_releases/2013/01.aspx#.UQVoNVK-Zkj ITU-T’s Study Group 16 http://www.itu.int/en/ITU-T/studygroups/2013-2016/16/Pages/default.aspx has agreed first-stage approval (consent) of the much-anticipated standard known formally as Recommendation ITU-T H.265 or ISO/IEC 23008-2. It is the product of collaboration between the ITU Video Coding Experts Group (VCEG) and the ISO/IEC Moving Picture Experts Group (MPEG). ITU-T H.265 / ISO/IEC 23008-2 HEVC will provide a flexible, reliable and robust solution, future-proofed to support the next decade of video. The new standard is designed to take account of advancing screen resolutions and is expected to be phased in as high-end products and services outgrow the limits of current network and display technology. Companies including ATEME, Broadcom, Cyberlink, Ericsson, Fraunhofer HHI, Mitsubishi and NHK have already showcased implementations of HEVC. The new standard includes a ‘Main’ profile that supports 8-bit 4:2:0 video, a ‘Main 10’ profile with 10-bit support, and a ‘Main Still Picture’ profile for still image coding that employs the same coding tools as a video ‘intra’ picture. The ITU/ISO/IEC Joint Collaborative Team on Video Coding (JCT-VC) (formerly JVT) will continue work on a range of extensions to HEVC 2. Obviously, the future standard for 3D audio belongs to the same standard (or standard family) ISO/IEC 23008. The audio part is ISO/IEC 23008-3, better known as MPEG-H part 3. 3. Here a global update on MPEG standard, presented by Leonardo Chiariglione himself. (Paper date: 26th June 2012) http://www.ieee-bmsb2012.org/images/program/BMSB2012_Keynote_2_MPEG_standards_supporting_the_evolution_of_broadcast_media_Leonardo.pdf Updates: - p. 10 presents the intended timeline for the standardization process, including 3D audio. New: We might have a bit more time than I have thought, which is good news. CD stands for committee draft. I guess they will start on the first working draft in Vienna, summer 2013. (I have posted the schedule of next MPEG meetings, within this thread.) - p. 34ff: No systems and video without audio... - p. 35-37: 3D audio requirements Judge yourself if Ambisonics would fit to fulfill this requirement list. (A clear yes here, if I have anyting to say about...) - p. 38 Envisioned architecture Ambisonics is actually included, as audio scene input into the first encoder. BUT: This is still a very crude scheme, not anything eleaborated. - The two encoder stages need some explication, or elaboration. I could imagine what they mean, more or less. However, as an acitectural diagram this is either a bit confused, or maybe heavily underspecified. - Indeed, the 500 bit/s for 3D audio seems to be a bit bit-starved, what Mr. Chiariglione actually seems to admit himself. (p. 42) Parametric compression might achieve this rate, but how to reconcile this with the requirement list? (quality of decoded sound perceptionally transparent; note also that we are talking about UHD television and cinema audio, in this case, do it well?) - The 64 kbit/s stream to mobile phones/devices seems to be completely outfashioned, in a time of readiy available UMTS, HSPA , LTE etc.) Stay at 128kbit/s or 256kbit/s, as anybody else in this industry? (Please don't be worse than any YouTube stream, ok? Just speaking for the new generation, which righteously expects some minimum quality over their handy earbuds...) Nobody will listen to 3D audio on GSM phones, pretty safe bet. Smart phone TV will be more like video transmitted via Internet, classical broadcast TV probably included but hardly the main thing... - p.39: Immersive and enveloping audio expeience Immersive should mean high quality, not cheating in a race for the lowest possible bitrate. -Home theater: p. 41ff The presented .AMB based proposal, 3rd horiz. /2nd vertical order (as option including 3 or 5 separate front speakers) seems to be sufficiently strong to be decoded to this typical but high end loudspeaker configuration. Would also need significantly less transmission rate than 22.2, which seems to be a factor here. (Maybe they will take 1,5 MBit/s as upper rate limit, have a look at p. 42) - p. 46: Flexible rendering I leave the rest to your own interpretation, and good judgement. I hope there will be a little bit more support coming from this list, which is heavily involved into Ambisonics reasearch and practical implementation. And I fully believe that sursound is a very competent list/place... Best regards, Stefan Schreiber P.S.: Further updates on the Shanghai and Genève meetings heavily needed, IMO. Mr. Pallone et al., the CfP is issued by now, and it is time to present something. Anyway, I have
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
I am apologizing for the HTML -- plain text msg. formatting errors, I never seem to learn this. MPEG Surround was also defined as one of the MPEG-4 Audio Object Types http://en.wikipedia.org/wiki/MPEG-4_Part_3#MPEG-4_Audio_Object_Types in 2007.[8] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-8 There is also the MPEG-4 Low Delay MPEG Surround object type (LD MPEG Surround), which was published in 2010.[9] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-9[10] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-saoc-ld-mpeg-surround-doc-10 The Spatial Audio Object Coding (SAOC) was published as MPEG-D Part 2 - ISO/IEC 23003-2 in 2010 and it extends MPEG Surround standard by re-using its spatial rendering capabilities while retaining full compatibility with existing receivers. MPEG SAOC system allows users on the decoding side to interactively control the rendering of each individual audio object (e.g. individual instruments, vocals, human voices).[2] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-mpeg-standards-2[3] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-mpeg-terms-of-reference-3[11] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-11[12] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-12[13] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-13[14] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-14[15] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-15 There is also the Unified Speech and Audio Coding http://en.wikipedia.org/wiki/Unified_Speech_and_Audio_Coding (USAC) which will be defined in MPEG-D Part 3 - ISO/IEC 23003-3 and ISO/IEC 14496-3:2009/Amd 3.[16] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-16[17] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-17 MPEG-D MPEG Surround parametric coding tools are integrated into the USAC codec.[18] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-18 Oops... You know what I mean, anyway!:-) The rest was quite legible, though... Best, Stefan ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
Hi ... Here some expert view on the technical background, presented by some company in this area: http://www.atsc.org/cms/pdf/pt2/07-Jean-Marc_Jot_3D_Audio.pdf Current state of the art. Look for example to p. 6, perceptual attributes that characterize natural, 3D-audio. (and especially proximity and depth. How good is HOA at that?!) High-order Ambisonics is mentioned (interestingly together with 22.2, which is fixed channel; but should play together very well with HOA!) p. 10: surround sound virtuzalization for headphones or frontal loudspeakers: the latter certainly based on X-talk cancellation, Ambiophonics style. I am getting increasingly aware of recent work on MPEG SAOC (spacial audio object coding), also. Moving Picture Experts Group http://en.wikipedia.org/wiki/Moving_Picture_Experts_Group (MPEG) issued a call for proposals on MPEG Spatial Audio Coding in March 2004. The group decided that the technology that would be the starting point in standardization process, would be a combination of the submissions from two proponents - Fraunhofer IIS / Agere Systems and Coding Technologies / Philips.[5] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-mpeg-surround-tutorial-5 ... MPEG Surround was also defined as one of the MPEG-4 Audio Object Types http://en.wikipedia.org/wiki/MPEG-4_Part_3#MPEG-4_Audio_Object_Types in 2007.[8] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-8 There is also the MPEG-4 Low Delay MPEG Surround object type (LD MPEG Surround), which was published in 2010.[9] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-9[10] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-saoc-ld-mpeg-surround-doc-10 The Spatial Audio Object Coding (SAOC) was published as MPEG-D Part 2 - ISO/IEC 23003-2 in 2010 and it extends MPEG Surround standard by re-using its spatial rendering capabilities while retaining full compatibility with existing receivers. MPEG SAOC system allows users on the decoding side to interactively control the rendering of each individual audio object (e.g. individual instruments, vocals, human voices).[2] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-mpeg-standards-2[3] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-mpeg-terms-of-reference-3[11] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-11[12] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-12[13] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-13[14] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-14[15] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-15 There is also the Unified Speech and Audio Coding http://en.wikipedia.org/wiki/Unified_Speech_and_Audio_Coding (USAC) which will be defined in MPEG-D Part 3 - ISO/IEC 23003-3 and ISO/IEC 14496-3:2009/Amd 3.[16] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-16[17] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-17 MPEG-D MPEG Surround parametric coding tools are integrated into the USAC codec.[18] http://en.wikipedia.org/wiki/MPEG_Surround#cite_note-18 Source: http://en.wikipedia.org/wiki/MPEG_Surround Now some recent AES input: http://www.aes.org/technical/documentDownloads.cfm?docID=418 Because some of the established players are already presenting their own proposals (Fraunhofer Institut being very close to the MPEG/ISO anyway, because of standard-defining work on perceptional audio compression etc.), it might be a good strategy to define an open source 3D audio (next gen. surround sound) proposal based on Ambisonics/HOA - just forgetting the patent issues which might even not exist anyway. This open standard could be included into other standards - and last but not least - software and hardware products. As nobody seems to own Ambisonics technology, I think an open source solution for 3D audio based on Ambisonics would fit well to Xiph.org and it's recent work on audio codecs/technology, including the newish Opus codec recognised by the IETF as official Internet audio standard. http://en.wikipedia.org/wiki/Opus_%28audio_format%29 If this makes sense or not, we have/had to look what happens elsewhere. My political view would be that HOA doesn't seem to have some big lobby at the MPEG/ISO, which might be biased heavily to parametric and object-based solutions, see MPEG-D part 1 and even more part 2... Now everybody should be confused including myself, after some serious standard name dropping ... :-) Best regards Stefan P.S.: USAC (Unified Speech and Audio Codec), part 3 of MPEG-D , could have a new and very powerful competition in IETF's/Xiph's (free) Opus Codec. Note that Opus includes some propietary technology for speech compression, which has been gifted by evil Microsoft. Now M$ is a bit less evil... Your view on this, Gregory? ;-) Gregory Maxwell wrote: On Sun, Jan 20, 2013 at 6:09 PM, Stefan Schreiber st...@mail.telepac.pt wrote: This is a typical FUD approach presentend by the
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
On 23 Jan 2013, at 02:53, Stefan Schreiber st...@mail.telepac.pt wrote: P.S.: FLAC was the first widely used codec for lossless compression, so here the commercial competition has a problem. How so? FLAC has a different design objective than some of the commercial lossless codecs. FLAC was intended mostly for rippers, i.e. people who want to encode a lot of CDs, and store them and play them back on computers, so a big emphasis was encoding speed. Other algorithms are designed for max. compression and are thus slower and use more CPU but use less space. Others are optimized for minimal CPU use during decompression, such as to be workable on low power CPUs in portable devices. FLAC is but a choice, and not always the best one, from a technical point of view, even though it's free. -- next part -- A non-text attachment was scrubbed... Name: smime.p7s Type: application/pkcs7-signature Size: 4853 bytes Desc: not available URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20130123/9780edb4/attachment.bin ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
On Wed, Jan 23, 2013 at 03:21:46PM +0100, Ronald C.F. Antony wrote: How so? FLAC has a different design objective than some of the commercial lossless codecs. FLAC was intended mostly for rippers, i.e. people who want to encode a lot of CDs, and store them and play them back on computers, so a big emphasis was encoding speed. Other algorithms are designed for max. compression and are thus slower and use more CPU but use less space. Others are optimized for minimal CPU use during decompression, such as to be workable on low power CPUs in portable devices. Quoted from the FLAC documentation: FLAC is asymmetric in favor of decode speed. Decoding requires only integer arithmetic, and is much less compute-intensive than for most perceptual codecs. Real-time decode performance is easily achievable on even modest hardware. There is absolutely nothing in the documentation that suggests that FLAC was designed for rippers. OTOH it was designed to be streamable, which suggest another type of use. Ciao, -- FA A world of exhaustive, reliable metadata would be an utopia. It's also a pipe-dream, founded on self-delusion, nerd hubris and hysterically inflated market opportunities. (Cory Doctorow) ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
Marc Lavallée wrote: Stefan, I was not stating that MPEG and ISO are evil. As a hobbyist, my question is: how Ambisonics might be included in a standard format made by the industry for the industry, that everybody would then have to use if there are no viable (and simple) alternative appart from the AMB format. I can only wait and see. -- Marc You don't have to use any standard. But I see that especially MPEG has defined standards which are used pretty everywhere, included in the freeish Android OS based on Linux and Java. Clients wouldn't buy phones which don't support MP3 or AAC or AVC codecs, every single one is a MPEG standard. You could replace these maybe with Vorbis/Opus/ or Daala video codec (to be defined), but sometimes the first solutions will stay because people don't bother. But at least you see that I am informed about the free competition, if citing topics like Daala etc. :-) At first you need a real standard for 3D audio, I would say. (Dolby Atmos won't do it for home use, UHD TV etc.) Best, Stefan P.S.: FLAC was the first widely used codec for lossless compression, so here the commercial competition has a problem. ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
Marc Lavallée wrote: Stefan Schreiber st...@mail.telepac.pt a écrit : The Android OS is open, although not entirely: http://en.wikipedia.org/wiki/Android_%28operating_system%29#Licensing Very closely controlled by Google, even if being based on Linux and some (propietary) hack of Java? Yes, developed and controlled by Google (because it owns the Android copyright...). As for Java, it is now a free software and its implementation for Android (Dalvik), is free too. Really?! Java is not free, unless you are referring (only) to the programming language. (Libraries? VM?) Android is a big step in the right direction (as least in terms of licensing). Google is huge, but there are other free OSes based on Linux for phones and small devices, that started long before Android. Also, Ubuntu is now targeting the phone and tablet market (without using Java). I was (obviously) aware of Ubuntu, Firefox OS etc. Now I don't hate Android, but what about any Linux where you can't install your own software? This is supposedly open? Not entirely open? (Laughing...) (Answer: Open for the industry, not user. ) Android is open for both the industry and the (tech savvy) users. We can install our own software on tons of different Android devices. Users can install free software without the Google Market app, using the F-Droid app, or manually with apk packages. It doesn't work always, and therefore is a hack. (Because manufacturers/providers try to lock the system.) Have you ever installed a free Android update?;-) The Replicant OS is a fork of Android, using only free software (except from some bootloaders and drivers): http://en.wikipedia.org/wiki/Replicant_%28operating_system%29 Most mainstream phones work with non-free drivers and bootloaders, but there are some phones and SoC (system on a chip) devices that are providing free drivers. From most to some phones, but if I think on which Android is based it looks like an accident.:-) My point is that it's possible to build ambisonics players using cheap technologies with free software only; there's maybe an opportunity to develop a parallel industry for ambisonics content and delivery (I'm being naïve and idealistic). I am abolutely in favour of this, even considering that a free3D audio codec could be developped without the MPEG, or say outside the MPEG. Currently, I try to evaluate what is happening... Best, Stefan ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
Stefan Schreiber st...@mail.telepac.pt a écrit : As for Java, it is now a free software and its implementation for Android (Dalvik), is free too. Really?! Java is not free, unless you are referring (only) to the programming language. (Libraries? VM?) Hi Stephan. The Java language and its specifications are free, the Gnu classes are free, the Dalvik VM is free, and most of the Oracle (Sun) implementation is free. That's not so bad. I was (obviously) aware of Ubuntu, Firefox OS etc. Obviously. Android is open for both the industry and the (tech savvy) users. We can install our own software on tons of different Android devices. Users can install free software without the Google Market app, using the F-Droid app, or manually with apk packages. It doesn't work always, and therefore is a hack. (Because manufacturers/providers try to lock the system.) Apps from the F-Droid market works on many Android phones and devices. Phones from providers can be rooted and reflashed, but I was thinking more about other kinds of SoC devices that we can buy (and proudly hack). Have you ever installed a free Android update?;-) No. Do you mean free as beer? My point is that it's possible to build ambisonics players using cheap technologies with free software only; there's maybe an opportunity to develop a parallel industry for ambisonics content and delivery (I'm being naïve and idealistic). I am abolutely in favour of this, even considering that a free3D audio codec could be developped without the MPEG, or say outside the MPEG. Great! Currently, I try to evaluate what is happening... Best, Stefan Remember that MPEG is creating proprietary, industrial and commercial standards using lots of patents. How Ambisonics can co-exist? -- Marc ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
Marc Lavallée wrote: Remember that MPEG is creating proprietary, industrial and commercial standards using lots of patents. How Ambisonics can co-exist? -- Marc The MPEG is part of the International Standard Organisation (ISO), in fact it was founded by both ISO and IEC. http://en.wikipedia.org/wiki/Iso ISO has 162 national members http://en.wikipedia.org/wiki/Countries_in_International_Organization_for_Standardization,[2] http://en.wikipedia.org/wiki/Iso#cite_note-About_ISO-2 out of the 205 http://en.wikipedia.org/wiki/List_of_sovereign_states total countries in the world. In this context, I absolutely don't understand what the term propietary standard means. A standard has to be defined, and somebody has to be responcible. The ISO is an international organization formed by national standard committees. If I buy some lights (I even don't use the word lightbulb...), it is a good thing that these work in different countries, and there are no mechanical problems if I want to install the. It is a good thing if railway lines have the same width in different places countries, airport communications works everywhere with available equipment, etc. Respective to Mpeg, I greatly admire the work they have done for video/TV etc. If you should have used free Divx;-) or x264, these are still based on MPEG's work. So what? http://en.wikipedia.org/wiki/Moving_Picture_Experts_Group The direct forerunner was the Joint Photographic Experts Group. Everybody uses their format, how it seems... Now, it seems to me that Ambisonics and MPEG audio easily could co-exist. Remember that MPEG is creating proprietary, industrial and commercial standards using lots of patents. Propietary is actually wrong, because you can license ISO standards under known terms. --- But anyway, you are really not informed at all... Because the ISO is issuing lots of open standards, which matter literally everywhere. http://www.open-std.org/jtc1/sc22/wg21/ ISO http://www.iso.ch//IEC http://www.iec.ch/ JTC1 http://www.jtc1.org//SC22 http://www.open-std.org/JTC1/SC22//WG21 http://www.open-std.org/jtc1/sc22/wg21/ is the international standardization working group for the programming language C++. Yeah, you never should use this programming language again. But then, things might get even more complicated for you to avoid THEIR standads... http://en.wikipedia.org/wiki/C_%28programming_language%29 In 1989 the American National Standards Institute http://en.wikipedia.org/wiki/American_National_Standards_Institute published a standard for C (generally called ANSI C http://en.wikipedia.org/wiki/ANSI_C or C89). The next year, the same specification was approved by the International Organization for Standardization http://en.wikipedia.org/wiki/International_Organization_for_Standardization as an international standard (generally called C90). ISO later released an extension to the internationalization http://en.wikipedia.org/wiki/Internationalization_and_localization support of the standard in 1995, and a revised standard (known as C99 http://en.wikipedia.org/wiki/C99) in 1999. The current version of the standard (now known as C11 http://en.wikipedia.org/wiki/C11_%28C_standard_revision%29) was approved in December of 2011. So, now you know what evil ANSI and evil ISO are, and maybe even you are using some stuff of these evil, commercial guys. This is hard to avoid. Even the bytecodes for text messages are coded in evil ANSI and ISO way, which proves my case. http://en.wikipedia.org/wiki/Universal_Character_Set The International Organization for Standardization http://en.wikipedia.org/wiki/International_Organization_for_Standardization (ISO) set out to compose the universal character set in 1989 ... Damned... The ISO Capitalists (or Communists?!) took over, and nobody stopped them when it was time! ;-) Bye, Stefan ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
Ok, the citings and links weren't presented in the desired form. I guess this is because there was no clear ISO standard for HTML citings...(In fact, maybe this is because I was copying HTML to plain text format, forced by the sursound list owners to do so. :-) ) Anyway, I am completely shocked that even HTML seems to be based on some ISO stuff. http://en.wikipedia.org/wiki/Standard_Generalized_Markup_Language HTML http://en.wikipedia.org/wiki/HTML, XHTML http://en.wikipedia.org/wiki/XHTML, and XML http://en.wikipedia.org/wiki/XML are all examples of SGML-based languages. Shock, awe, trembling... O:-) Good night, Stefan Stefan Schreiber wrote: Marc Lavallée wrote: Remember that MPEG is creating proprietary, industrial and commercial standards using lots of patents. How Ambisonics can co-exist? -- Marc The MPEG is part of the International Standard Organisation (ISO), in fact it was founded by both ISO and IEC. etc. ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
Hi Stefan, I doubt if B+ would meet the currently perceived needs of cinema surround mixers/producers since it does not have the ability to go discrete. B++ might be enough - that's first order + 5.1 (I just made that up :-)). A better option would be at least third order, preferably fifth - to get the most bang for buck - but to fit in the 22.2 channels that seem to be coming over the horizon fast, maybe fourth would work better in terms of channel count. I don't, personally, think that first order is a good choice for cinema for anything other than home use. It certainly can be pressed into use for large areas (been there, done that, got not just the T shirt but the entire wardrobe) but it would really struggle in anything other than the smaller art cinemas. The biggest limitation to the whole thing is the availability of higher order microphones, though Eigenmikes are becoming more widely available and one can hope that Peter Craven's new ideas (http://www.findaphd.com/search/ProjectDetails.aspx?PJID=40193) pan out and give us at least a good second order microphone. However, if you are constructing the soundscapes entirely from scratch, such considerations do not really matter - in fact, to that end, improving the use of spot microphones to generate convincing, realistic higher order recordings is probably at least as important. On audio objects and where they should be mixed in, I have some sympathy with your point that they should only be used in the studio but in purely practical terms (and, again, only really for non-home use) they can be very useful at the decoding stage where you are dealing with very irregular arrays, so don't rule them out. All the best Dave On 20 January 2013 04:11, Stefan Schreiber st...@mail.telepac.pt wrote: Reading back, and evaluating... http://steinhardt.nyu.edu/scmsAdmin/uploads/005/384/Miles_Fulwider_Thesis.pdf I believe B+ classic could serve as a convincing 1st proposal for a sound-field based 3D cinema audio system. (And therefore, as a general surround format). The very obvious changes could/would be: - You have at least 3 front channels behind the screen (up to 5 in Dolby Atmos), not 2 - Which Ambisonics order would you need for cinema use? Might even 1st order suffice (provided there is a direct/precise front) - LFE channel(s) should (probably) be treated in a simple channel-loudspeaker configuration, such as the front channels. (You also could code an LFE soundfield, B format style. Or you don't code LFE at all - but we are talking about cinema use, in which case LFE seems to matter.) - If using a sound field approach, you would not want to mix soundfields this with audio objects at rendering time. (Rather, use audio objects in the studio. Mixing stage, not decoding stage...) - The object audio proposals are all driven by the need to cope for many different loudspeaker layouts. This issue is no problem for Ambisonics/soundfields... (Could say much more about this point, but it is too late, and why should I...:-) ) Best, Stefan Schreiber Richard Furse wrote: Very interesting post following discussion. I've actually been added very recently to the IST/37 committee, which apparently is a close relative to the MPEG one. However, I've not talked to any other members so far and I'm not sure how all this stuff works just yet! In other news, I spent a bit of time last year putting together a C API for object streaming etc (including Ambisonics). Hopefully it roughly captures the suggestions/requirements below. This project is now in a state where there's a fairly short API that seems to work and a basic SDK which provides some basic reference tools like a simple stereo renderer, lossless file format and network streaming. However, this isn't part of the API/Spec itself - the intent is that the C API should be independent of actual rendering/stream/persistence formats (although a reference is provided), so would hopefully play nice with Atmos/MDA. That said, I've not seen a *technical* spec for either of these yet, so there's a fair bit of guesswork happening. Certainly what's there now seems to work well for me, so far. :-/ The provisional spec has been bounced off a few folk but I've not heard much back (though I also had some email problems at a similar time). I'm wondering about releasing the API and SDK using some kind of open source license. Anyway - if folk are interested in more detail, please get in touch off-list! Best wishes, --Richard -Original Message- From: sursound-boun...@music.vt.edu [mailto:sursound-boun...@music.vt.edu] On Behalf Of Stefan Schreiber Sent: 06 January 2013 02:00 To: Surround Sound discussion group Subject: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style... Dear colleagues... I would like to remember everybody interested or already being involved that ITU/MPEG plan to define
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
Hi Dave, I'll throw in... On 20 Jan 2013, at 9:02 am, Dave Malham dave.mal...@york.ac.uk wrote: The biggest limitation to the whole thing is the availability of higher order microphones, Actually, as we've heard, upsampling from a 1st order mic can give very good results. Svein Berge's Harpex (http://www.harpex.net) is available as a plugin... which means the production path open. though Eigenmikes are becoming more widely available and one can hope that Peter Craven's new ideas (http://www.findaphd.com/search/ProjectDetails.aspx?PJID=40193) pan out and give us at least a good second order microphone. It'll be great to see 'native' HOA mics on the market My best, Jo ~~ Joseph Anderson Artist: http://joseph-anderson.org Ambisonic Toolkit: http://ambisonictoolkit.net -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20130120/c61fd3dc/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
Hi Jo, To some extent, yes, but only if you are working with material which can tolerate the artefacts that blind source separation algorithms will, sooner or later - and usually sooner - generate. Such algorithms, including those in Harpex, are getting much better (I can remember hearing some really terrible earlier attempts) but, so far anyway, it is always possible to find some material that will screw them up. There are two factors which will reduce this as time goes on - the continuing improvements in the technology and the fact that much of the audience these days have perceptions that are so screwed up by listening to compressed audio that maybe the artefacts maybe won't be heard by them anyway :-) All the best Dave On 20 January 2013 11:58, Joseph Anderson j.l.ander...@phonecoop.coop wrote: Hi Dave, I'll throw in... On 20 Jan 2013, at 9:02 am, Dave Malham dave.mal...@york.ac.uk wrote: The biggest limitation to the whole thing is the availability of higher order microphones, Actually, as we've heard, upsampling from a 1st order mic can give very good results. Svein Berge's Harpex (http://www.harpex.net) is available as a plugin... which means the production path open. though Eigenmikes are becoming more widely available and one can hope that Peter Craven's new ideas (http://www.findaphd.com/search/ProjectDetails.aspx?PJID=40193) pan out and give us at least a good second order microphone. It'll be great to see 'native' HOA mics on the market My best, Jo ~~ Joseph Anderson Artist: http://joseph-anderson.org Ambisonic Toolkit: http://ambisonictoolkit.net -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20130120/c61fd3dc/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound -- As of 1st October 2012, I have retired from the University, so this disclaimer is redundant These are my own views and may or may not be shared by my employer Dave Malham Ex-Music Research Centre Department of Music The University of York Heslington York YO10 5DD UK 'Ambisonics - Component Imaging for Audio' ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
Hence the discussion re MPEG...! ;-) On 20 Jan 2013, at 4:53 pm, Dave Malham dave.mal...@york.ac.uk wrote: Hi Jo, To some extent, yes, but only if you are working with material which can tolerate the artefacts that blind source separation algorithms will, sooner or later - and usually sooner - generate. Such algorithms, including those in Harpex, are getting much better (I can remember hearing some really terrible earlier attempts) but, so far anyway, it is always possible to find some material that will screw them up. There are two factors which will reduce this as time goes on - the continuing improvements in the technology and the fact that much of the audience these days have perceptions that are so screwed up by listening to compressed audio that maybe the artefacts maybe won't be heard by them anyway :-) All the best Dave On 20 January 2013 11:58, Joseph Anderson j.l.ander...@phonecoop.coop wrote: Hi Dave, I'll throw in... On 20 Jan 2013, at 9:02 am, Dave Malham dave.mal...@york.ac.uk wrote: The biggest limitation to the whole thing is the availability of higher order microphones, Actually, as we've heard, upsampling from a 1st order mic can give very good results. Svein Berge's Harpex (http://www.harpex.net) is available as a plugin... which means the production path open. though Eigenmikes are becoming more widely available and one can hope that Peter Craven's new ideas (http://www.findaphd.com/search/ProjectDetails.aspx?PJID=40193) pan out and give us at least a good second order microphone. It'll be great to see 'native' HOA mics on the market My best, Jo ~~ Joseph Anderson Artist: http://joseph-anderson.org Ambisonic Toolkit: http://ambisonictoolkit.net -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20130120/c61fd3dc/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound -- As of 1st October 2012, I have retired from the University, so this disclaimer is redundant These are my own views and may or may not be shared by my employer Dave Malham Ex-Music Research Centre Department of Music The University of York Heslington York YO10 5DD UK 'Ambisonics - Component Imaging for Audio' ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound ~~ Joseph Anderson Artist: http://joseph-anderson.org Ambisonic Toolkit: http://ambisonictoolkit.net -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20130120/6665dc2a/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
Hello all, Since I've been named I guess a quick comment might be in order. Of course, Dave is correct about the potential for artifacts of bss algorithms and that means that a single first-order b-format stream is sufficient for all uses, even with upsampling and whatnot. More channels are required to fully harness large loudspeaker arrays, and the main options on the table are then to add direct loudspeaker channels, vbap-panned audio objects or higher order ambisonics. Another option exists, using the mentioned bss-related methods that I have some interest in, so I'll throw it out there: If the audio material is distributed as several 1st order b-format streams, each having only a small number of sound sources, then any bss-related artifacts can be limited below any chosen level, limited only by the number of available channels. This assumes that each stream is decoded separately with a parametric decoder. You would for example put dialogue on a separate b-format stream. Center-positioned speech would then decode to the center speaker only, which is a basic requirement. Since audio tracks are typically downmixed from a multitude of tracks anyway, the need of downmixing to a handful of b-format streams shouldn't affect the workflow of sound designers much. Once suitable streams for the highest-quality targeted systems are created, it would be trivially simple to downmix them to a suitable number of b-format streams for lower-quality media intended for smaller loudspeaker arrays. Cheers, Svein From: Dave Malham dave.mal...@york.ac.uk Subject: Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style... Date: 20. januar 2013 17:53:31 GMT+01:00 To: Surround Sound discussion group sursound@music.vt.edu Reply-To: Surround Sound discussion group sursound@music.vt.edu Hi Jo, To some extent, yes, but only if you are working with material which can tolerate the artefacts that blind source separation algorithms will, sooner or later - and usually sooner - generate. Such algorithms, including those in Harpex, are getting much better (I can remember hearing some really terrible earlier attempts) but, so far anyway, it is always possible to find some material that will screw them up. There are two factors which will reduce this as time goes on - the continuing improvements in the technology and the fact that much of the audience these days have perceptions that are so screwed up by listening to compressed audio that maybe the artefacts maybe won't be heard by them anyway :-) All the best Dave On 20 January 2013 11:58, Joseph Anderson j.l.ander...@phonecoop.coop wrote: Hi Dave, I'll throw in... On 20 Jan 2013, at 9:02 am, Dave Malham dave.mal...@york.ac.uk wrote: The biggest limitation to the whole thing is the availability of higher order microphones, Actually, as we've heard, upsampling from a 1st order mic can give very good results. Svein Berge's Harpex (http://www.harpex.net) is available as a plugin... which means the production path open. though Eigenmikes are becoming more widely available and one can hope that Peter Craven's new ideas (http://www.findaphd.com/search/ProjectDetails.aspx?PJID=40193) pan out and give us at least a good second order microphone. It'll be great to see 'native' HOA mics on the market My best, Jo ~~ Joseph Anderson Artist: http://joseph-anderson.org Ambisonic Toolkit: http://ambisonictoolkit.net -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20130120/c61fd3dc/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound -- As of 1st October 2012, I have retired from the University, so this disclaimer is redundant These are my own views and may or may not be shared by my employer Dave Malham Ex-Music Research Centre Department of Music The University of York Heslington York YO10 5DD UK 'Ambisonics - Component Imaging for Audio' ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20130120/62a198bd/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
is sufficient for all uses that was supposed to read… is not sufficient for all uses… Svein ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
Dave Malham wrote: Hi Stefan, I doubt if B+ would meet the currently perceived needs of cinema surround mixers/producers since it does not have the ability to go discrete. B++ might be enough - that's first order + 5.1 (I just made that up :-)). :-) I also fear(ed) that 5.1 + FOA (B++) won't make it...8-) A better option would be at least third order, preferably fifth - to get the most bang for buck - but to fit in the 22.2 channels that seem to be coming over the horizon fast, maybe fourth would work better in terms of channel count. Ok. But you don't have to fit into any channel count! We are just talking about several (few) new file formats?! Auro-3D is 11.1, so you have another format. (You have to decode Ambisonics anyway, and also any object-based approach.) I don't, personally, think that first order is a good choice for cinema for anything other than home use. It certainly can be pressed into use for large areas (been there, done that, got not just the T shirt but the entire wardrobe) but it would really struggle in anything other than the smaller art cinemas. This was my question, so this one is maybe answered. However, I believe it is helpful to start with the most basic approach, and you/we will see why you would need a higher order approach. The MPEG won't look into these issues, all the standardization process is very much fast-track. (Necessary discussions have to happen somewhere, so... ;-) ) The biggest limitation to the whole thing is the availability of higher order microphones, though Eigenmikes are becoming more widely available and one can hope that Peter Craven's new ideas (http://www.findaphd.com/search/ProjectDetails.aspx?PJID=40193) pan out and give us at least a good second order microphone. However, if you are constructing the soundscapes entirely from scratch, such considerations do not really matter - in fact, to that end, improving the use of spot microphones to generate convincing, realistic higher order recordings is probably at least as important. They will mix cinema sound from track, don't worry too much about Eigenmikes... On audio objects and where they should be mixed in, I have some sympathy with your point that they should only be used in the studio but in purely practical terms (and, again, only really for non-home use) they can be very useful at the decoding stage where you are dealing with very irregular arrays, so don't rule them out. But this was/is the other issued which needed (needs...) some serious discussion. Thanks for the feedback, Stefan On 20 January 2013 04:11, Stefan Schreiber st...@mail.telepac.pt wrote: Reading back, and evaluating... http://steinhardt.nyu.edu/scmsAdmin/uploads/005/384/Miles_Fulwider_Thesis.pdf I believe B+ classic could serve as a convincing 1st proposal for a sound-field based 3D cinema audio system. (And therefore, as a general surround format). The very obvious changes could/would be: - You have at least 3 front channels behind the screen (up to 5 in Dolby Atmos), not 2 - Which Ambisonics order would you need for cinema use? Might even 1st order suffice (provided there is a direct/precise front) - LFE channel(s) should (probably) be treated in a simple channel-loudspeaker configuration, such as the front channels. (You also could code an LFE soundfield, B format style. Or you don't code LFE at all - but we are talking about cinema use, in which case LFE seems to matter.) - If using a sound field approach, you would not want to mix soundfields this with audio objects at rendering time. (Rather, use audio objects in the studio. Mixing stage, not decoding stage...) - The object audio proposals are all driven by the need to cope for many different loudspeaker layouts. This issue is no problem for Ambisonics/soundfields... (Could say much more about this point, but it is too late, and why should I... :-) ) Best, Stefan Schreiber ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
On Sat, Jan 5, 2013 at 9:00 PM, Stefan Schreiber st...@mail.telepac.pt wrote: Dear colleagues... I would like to remember everybody interested or already being involved that ITU/MPEG plan to define and issue some 3D audio standard (better: 3D audio standard framework) during this year. The 3D audio codec is meant to be part of the (wider) MPEG-H standard. Will the working group be creating a preference for a royalty free format— or will is be the normal RAND terms? Excessive patent encumbrances appears to be one of the things which originally blocked the deployment of B-format— and I don't see the situation as being any different today. Getting people deploy the hardware for good surround is enough of a barrier without the added cost of per-unit pricing and the resulting incompatibilities created by a failure to converge on a single standard. I strongly encourage anyone here looking to contribute to such a standards effort to decline to participate unless some effort is made to produce a result which is royalty free. ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
From: Gregory Maxwell gmaxw...@gmail.com To: Surround Sound discussion group sursound@music.vt.edu Sent: Monday, 21 January 2013 10:51 AM Subject: Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style... On Sun, Jan 20, 2013 at 6:09 PM, Stefan Schreiber st...@mail.telepac.pt wrote: This is a typical FUD approach presentend by the competition. If I have anything to say about, I'd say that any Ambisonis based approach would be patent-light, iof not patent-free. You confirm precisely the concern I raised: The result would likely be a royalty bearing format. How can you accuse me of FUD while concurrently affirming the concern I raised? If people believe there is a market for ambisonic distribution which has less than lossless quality but only if the bitrate is low enough then the parties who would profit from that should cooperate to produce a royalty free format so that their success will not be saddled with additional friction which will keep ambisonics in a niche. AAC + mpeg surround licensing costs over $1 decoder unit— to be added on top of the additional hardware costs (more DSP cpu cycles) required. Because the market for this technology barely exists the licensing costs could quite possibly keep it in a non-existing state. I think surround advocates would very much like it if support ended up in everything because the cost of doing so is only a modest hardware bump and some one time integration and testing costs. Per-unit royalties or even just the cost of negotiating a flat rate license strongly discourage deployment. In some markets like support in web browsers or in Free software which are distributed at no direct cost any royalty at all is a major or absolute barrier. I think it would be irrational for anyone who wants there to be a market for this to contribute to the development of a royalty bearing effort. You may disagree, but I still do not think it should be a concern which goes without mention. If pointing to an elephant in the room makes me guilty of FUD then so be it. P.S.: 1st order Ambisonics should be patent-free, nowadays. Higher orders can't be overpatented, because the theory behind is quite old. Certainly more than 20 years back... Yes, they are _now_. I think it would be a shame to revert ambisonics back to the bad— harder to deploy— state where including support for the distribution format required unfortunate per-unit or per-organization royalties and burdensome license negotiation. P.S. 2: And I for my part didn't patent Ambisonics of order =2 + front channels... Promised! :-D Thank you for not being personally evil. :P ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound From R Carpenter Australia Microsoft 1998 , Speaker configuration for WAVEFORMATEXTENSIBLE ...still applicable? -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20130120/49e0f363/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
Gregory Maxwell wrote: On Sun, Jan 20, 2013 at 6:09 PM, Stefan Schreiber st...@mail.telepac.pt wrote: This is a typical FUD approach presentend by the competition. If I have anything to say about, I'd say that any Ambisonis based approach would be patent-light, iof not patent-free. You confirm precisely the concern I raised: The result would likely be a royalty bearing format. How can you accuse me of FUD while concurrently affirming the concern I raised? Sorry, I didn't want to be personal. I trust persons, but I don't trust companies. Is this statement ok for you? If people believe there is a market for ambisonic distribution which has less than lossless quality but only if the bitrate is low enough then the parties who would profit from that should cooperate to produce a royalty free format so that their success will not be saddled with additional friction which will keep ambisonics in a niche. AAC + mpeg surround licensing costs over $1 decoder unit— to be added on top of the additional hardware costs (more DSP cpu cycles) required. Because the market for this technology barely exists the licensing costs could quite possibly keep it in a non-existing state. I think surround advocates would very much like it if support ended up in everything because the cost of doing so is only a modest hardware bump and some one time integration and testing costs. Per-unit royalties or even just the cost of negotiating a flat rate license strongly discourage deployment. Don't want to sound rude (again...), but I think this is a pseudo-problem. Surround headphones and many speakers for 3D audio will cost a bit more than normal headphones and 5.1 speakers (in cinemas you have a lot of speakers anyway...), so there will be some price increase. Undisclosured licensing fees if they exist don't seem to be the main cost factor, IMHO. Interest the people in doing something cool, don't think about the pennies or few dollars for some patent, which might be involved. (3D audio and real surround has to fit to movies/games etc.) People have just been very interested in 4K and/or OLED panels (CES), which currently are outrageously expensive. But prices will come down, like always. Talking about cinema surround and new headphones, I would say the involved costs don't look prohibitive as long as you see/hear results and don't end with 10+ different standards. (Iosono - as a company - seems to do quite well, and WFS doesn't seem to be cheap.) Dolby Atmos and Auro-3D are also not IP or patent-free, just to remember. In some markets like support in web browsers or in Free software which are distributed at no direct cost any royalty at all is a major or absolute barrier. This is why only MP3/AAC and AVC are universally supported? May this be Firefox/IE/Chrome/Safari, or the still widely used Flash-plugin... Also not personal, but I am increasingly getting tired of all these we need some free codec discussions. Theora is outfashioned.WebM never made it because AVC is simply better, and seems to be free completelty for personal use. (And after all the FUD from certain circles...) If it doesn't cost to include AVC and AAC into web browsers/plugins etc., maybe it is/was about Open Source principles? (Any discussion leads to nothing, because I tend to see this in a pragmatic way. For others it is about open lifestyle. The same people still buy an iPhone or an Android phone, both OS environments definitively not open. Linux admittedly is.) I think it would be irrational for anyone who wants there to be a market for this to contribute to the development of a royalty bearing effort. You may disagree, but I still do not think it should be a concern which goes without mention. If pointing to an elephant in the room makes me guilty of FUD then so be it. I agree to use as few patents as possible. But I don't agree to avoid some patent which might improve things a lot if you save just the mentioned pennies. Do we want some open standard or the best standard? Inventions are supposed to improve things. After this I have to care for licensed, open and hidden costs etc. But if I am at this point: The MPEG is introducing standards which are supposed to be best in class. (see HEVC) Consequently, I don't think they care a lot if patents are included. On the other hand, Mpeg codecs seem to have some track record to be reasonably priced, otherwise they wouldn't be used everywhere. P.S.: 1st order Ambisonics should be patent-free, nowadays. Higher orders can't be overpatented, because the theory behind is quite old. Certainly more than 20 years back... Yes, they are _now_. If so, there is competition, and IP owners certainly can't charge whatever they want. (As a patent holder, you want your patent actually to be applied. ) I think it would be a shame to revert ambisonics back to the bad— harder to deploy— state where including support for the
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
Gregory Maxwell wrote: On Sun, Jan 20, 2013 at 6:09 PM, Stefan Schreiber st...@mail.telepac.pt wrote: This is a typical FUD approach presentend by the competition. If I have anything to say about, I'd say that any Ambisonis based approach would be patent-light, iof not patent-free. You confirm precisely the concern I raised: The result would likely be a royalty bearing format. How can you accuse me of FUD while concurrently affirming the concern I raised? Gregory, I just was recognising that you are actually not working at Orange, because this is another person... :-[ I am fully apologizing! If we are talking about Xiph.org etc., you are exactly the person who should address concerns about IP questions. IMO, the patent issues are not very heavy. But I don't know enoug about. One hint: If we speak about surround headphones (with or without head tracking), the sweet spot is ead-sized, In this case, 1st order Ambisonics might be adequate to reproduce a 3D audio soundfield. (I am just a bit concerned about high frquencies, though...) In this case there are no patent issues involved, at least not with the file format and Internet transmission. (And maybe this is what Xiph.org et al should care about. Internet, codec and software questions.) Best regards, Stefan ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
Stefan Schreiber st...@mail.telepac.pt a écrit : If it doesn't cost to include AVC and AAC into web browsers/plugins etc., maybe it is/was about Open Source principles? (Any discussion leads to nothing, because I tend to see this in a pragmatic way. For others it is about open lifestyle. The same people still buy an iPhone or an Android phone, both OS environments definitively not open. Linux admittedly is.) The Android OS is open, although not entirely: http://en.wikipedia.org/wiki/Android_%28operating_system%29#Licensing The Replicant OS is a fork of Android, using only free software (except from some bootloaders and drivers): http://en.wikipedia.org/wiki/Replicant_%28operating_system%29 In any case, we probably agree. The difference is that I don't believe that in this case patents will matter a lot. IF there will be some 3D audio patent fee, it will be for handset makers/headpone makers etc. But don't worry about Apple or Samsung, they won't die. It does matter; there must be ways to promote and use ambisonics without playing the games of Apple, Google, Samsung, MPEG LA and other patent trollers. Here's an interesting article: http://www.forbes.com/sites/forbesleadershipforum/2012/11/15/a-powerful-new-weapon-against-patent-trolls/ Quotes: Apple and Google, the world’s two top innovators, now spend more on patents and patent litigation than on research and development. ...small and midsize companies with less than $1 billion in revenues now constitute 90% of the unique defendants in patent troll suits. Firms with less than $100 million in revenue represent 66% of the defendants. ... a staggering 89% of all patents reviewed by the USPTO are judged either partly or wholly invalid. The IETF or Xiph.org would probably demand something completely patent-free. Think that the next generation surround is something like MP3 or DD+. The first codec is an MPEG standard, the second is owned by Dolby. By any interpretation or say standard :-) , MP3 is more open than DD+. (Known technological base.) The next generation surround is anything we want, but I hope that ambisonics will stay patent free. -- Marc ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
Marc Lavallée wrote: Stefan Schreiber st...@mail.telepac.pt a écrit : If it doesn't cost to include AVC and AAC into web browsers/plugins etc., maybe it is/was about Open Source principles? (Any discussion leads to nothing, because I tend to see this in a pragmatic way. For others it is about open lifestyle. The same people still buy an iPhone or an Android phone, both OS environments definitively not open. Linux admittedly is.) The Android OS is open, although not entirely: http://en.wikipedia.org/wiki/Android_%28operating_system%29#Licensing Very closely controlled by Google, even if being based on Linux and some (propietary) hack of Java? Now I don't hate Android, but what about any Linux where you can't install your own software? This is supposedly open? Not entirely open? (Laughing...) (Answer: Open for the industry, not user. ) The Replicant OS is a fork of Android, using only free software (except from some bootloaders and drivers): http://en.wikipedia.org/wiki/Replicant_%28operating_system%29 In any case, we probably agree. The difference is that I don't believe that in this case patents will matter a lot. IF there will be some 3D audio patent fee, it will be for handset makers/headpone makers etc. But don't worry about Apple or Samsung, they won't die. It does matter; there must be ways to promote and use ambisonics without playing the games of Apple, Google, Samsung, MPEG LA and other patent trollers. Here's an interesting article: http://www.forbes.com/sites/forbesleadershipforum/2012/11/15/a-powerful-new-weapon-against-patent-trolls/ Quotes: Apple and Google, the world’s two top innovators, now spend more on patents and patent litigation than on research and development. Well, if speaking about patents, the world's top innovators are companies like IBM et al. Samsung files far more patents than Apple and Google, BTW. The latters earn their money mostly via software - patents never were decisive. Don't write about supposed patent trolls if your sources are Forbes etc. (This is business press, they certainly don't have any real clue about patents.) I don't care about Apple's litigation problems. (They had many patents cancelled, recently. I know this for sure. ) ...small and midsize companies with less than $1 billion in revenues now constitute 90% of the unique defendants in patent troll suits. Firms with less than $100 million in revenue represent 66% of the defendants. Yeah. If everybody who comes is a troll, you feel confirmed when you never pay. ... a staggering 89% of all patents reviewed by the USPTO are judged either partly or wholly invalid. Patent applications, right? The IETF or Xiph.org would probably demand something completely patent-free. Think that the next generation surround is something like MP3 or DD+. The first codec is an MPEG standard, the second is owned by Dolby. By any interpretation or say standard :-) , MP3 is more open than DD+. (Known technological base.) The next generation surround is anything we want, but I hope that ambisonics will stay patent free. -- Marc Now, this also doesn't make real sense to me. Either the patents have been filed in the past and stay valid, or not. To claim that the original Ambisonics patents were applied by patent trolls is what some people would like to hear, but I beg to differ. They weren't trolls... :-D Anyway, I still have to hear which patents should apply to HOA... (Maybe there are some, but it is better to know any real facts than to talk about patent trolls and FUD issues at night-time) Best, Stefan ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
Dave Malham wrote: Hi Stefan, I doubt if B+ would meet the currently perceived needs of cinema surround mixers/producers since it does not have the ability to go discrete. B++ might be enough - that's first order + 5.1 (I just made that up :-)). A better option would be at least third order, preferably fifth - to get the most bang for buck - but to fit in the 22.2 channels that seem to be coming over the horizon fast, maybe fourth would work better in terms of channel count. Just some further ideas, open for some discussion, and meant to obtain some possible .AMB or HOA based 3D audio standard... ;-) - For cinema 3D audio, you certainly could apply some mixed order approach, using a lower vertical order than horizontal order. You save a lot of channels... Without mixed orders: 4th order needs 25 channels, above 22.2 channel count. However: Current cinema 3D layouts don't use more than 3 levels! This would imply that you could use 2nd order for the vertical components, because any higher (vertical) order can't be resolved. Even this might be overkill: a) Dolby Atmos seems to have only 2 levels. b) 22.2 has three levels, but one is below surface. Also in this case, a 1st order vertical component looks to be sufficient. (Negative elevation, zero elevation, upper ring.) c) Auro-3D has three positive levels. But the highest level is just some over-the-head/voice of god loudspeaker. Again, 1st order for the vertical component(s) seems probably adequate. - Now, if 2nd order vertical component is enough FAPP: You easily fit even 6th order horzinal / 2nd order vertical B format (doesn't exist, ok) into 22.2 channels. 13 (horizontal 6th order) + 4 (vertical 2nd order) + (optional) up to 5 discreet front channels + 2 LFE channels fit into... 21.2. (Fill up one channel with silence, if this mattered... I won't claim any patent for this decisive idea!:-) ) (Naive 4th order was 25 channels, so probably 27 because of two additional LFE channels...) Of course I was planning to use some mixed order approach anyway, but here anybody could see how channels can be saved. (You can cut channels if nobody can hear them after decoding. Or let us assume that there is no advantage in using components for which the loudspeaker configuration would be underspecified... If you can hear a difference, the result of higher orders decoded to some undespecified array should be worse, not better.) I don't think that any .AMB or HOA format would have to fit into 22.2, anyway... I just wanted to demonstrate that you could use even 6th order within a still acceptable (global) channel number count. If we are admitting that all existing cinema 3D audio layouts will have about 2-3 levels. Maybe 4, but not more. Anyway, my current standard proposal would (still) be to use the classical 3rd/2nd mixed order .AMB format, extended with 2 LFE channels and (optionally) 3-5 front channels (direct channels). This is about 13-16 channels, which seems to be ok. (For home and mobile use, 3rd oder horizontal/1st order vertical fits into 8 channels, if the 8-channel limit still matters.) Up for discussion: - The sweet spot of any soundfield based approach for cinema audio should be equal or superior to 5.1. Can 3rd order .AMB deliver this requirement? (To compare, it might make sense to add the 3 to 5 direct front speakers, as I have proposed before. B format would refer to a 3rd order or mixed order - say 3rd/2nd order - soundfield. Compared to the original B+ format, we also have now 3 or 5 direct front channels, and 2 LFE channels.) - Could you further improve the decoding techniques for 2nd/3rd order soundfields, based on perceptional ideas (like 1st order Ambisonics/FOA), and/or via blind source separation algorithms (i.e. Harpex)? - If so, do we really need anything above 3rd order? (But 4th, 5th and 6th order can be done, even within 22.2 channels. Which has been demonstrated before,) Best regards, Stefan P.S.: To my best knowledge, it is not so clear how the best perceptional decoding strategies for 2nd or 3rd order Ambisonics should look like. Feedback welcome... ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
(Now in the thread-context where it belongs, sorry for my error before...) Dear Mr. Furse, many thanks for some real contributions, in the past and now... :-) Now, on a short note: There might not be sufficient time left to add ideas (and APIs) like presented to any standad they will issue in summer 2013 (?). Maybe something in this direction could be part of a 2nd (relatively independent) version, adding support for audio objects/object streaming etc. However, my impression is that the MPEG's intention is more to settle on something relatively simple, like 22.2, Auro-3D speaker layout etc. (Otherwise the standardization timeframe from 2012 to 2013 didn't make any sense) I think the best way you could help is to get into contact with the MPEG 3D Audio group, if there exists any real MPEG audio group. (This is the next problem. The MPEG has co-established video expert groups like JVT for AVC/H.264 and JCT for HEVC/H.265. I don't see anything like this for audio, correct me if I am wrong...) How things stand, interesting proposals might not be discussed/worked out because the standaization process itself has been very short-term. (They work on HEVC since 2010, many meetings.) http://www.ist37.org/index.xalter IST/37 prepares national contrbutions into the international standards committee, ISO/IEC JTC1/SC29 - two of whose working groups have achieved worldwide recognition for their work as MPEG and JPEG. Exactly. IST/37 is actually not only close to the MPEG, you have been and are a direct contributor. :-) If we talk about MPEG audio and Ambisonics, I think they should really listen to you. Best regards, Stefan Richard Furse wrote: Very interesting post following discussion. I've actually been added very recently to the IST/37 committee, which apparently is a close relative to the MPEG one. However, I've not talked to any other members so far and I'm not sure how all this stuff works just yet! In other news, I spent a bit of time last year putting together a C API for object streaming etc (including Ambisonics). Hopefully it roughly captures the suggestions/requirements below. This project is now in a state where there's a fairly short API that seems to work and a basic SDK which provides some basic reference tools like a simple stereo renderer, lossless file format and network streaming. However, this isn't part of the API/Spec itself - the intent is that the C API should be independent of actual rendering/stream/persistence formats (although a reference is provided), so would hopefully play nice with Atmos/MDA. That said, I've not seen a *technical* spec for either of these yet, so there's a fair bit of guesswork happening. Certainly what's there now seems to work well for me, so far. :-/ The provisional spec has been bounced off a few folk but I've not heard much back (though I also had some email problems at a similar time). I'm wondering about releasing the API and SDK using some kind of open source license. Anyway - if folk are interested in more detail, please get in touch off-list! Best wishes, --Richard -Original Message- From: sursound-boun...@music.vt.edu [mailto:sursound-boun...@music.vt.edu] On Behalf Of Stefan Schreiber Sent: 06 January 2013 02:00 To: Surround Sound discussion group Subject: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style... Dear colleagues... I would like to remember everybody interested or already being involved that ITU/MPEG plan to define and issue some 3D audio standard (better: 3D audio standard framework) during this year. The 3D audio codec is meant to be part of the (wider) MPEG-H standard. This all makes a lot of sense, 'cos ;-) there is already some competition around: 1. Hamasaki 22.2, well known as (audio) part of former UHDTV (Super Hi-vision) proposals. 2. http://www.auro-3d.com/system/listening-formats (Note: a) The Auro-3D® Engine comprises: Auro Codec: The revolutionary codec that delivers native, discrete Auro-3D® content. Auro-Matic: The groundbreaking up-mixing algorithm that converts legacy content into the Auro- 3D® format. Auro-3D® Headphone: Like other audio configurations, similar results can be achieved with headphones that use binaural technology. b) Film, Broadcast, Gaming, Mobile, Automotive and Multimedia industries are all searching for a next generation sound format. With 3D Stereoscopic imagery becoming commonplace, the time is right for an audio experience that matches this increased level of fidelity. Sound in 3D is clearly the next step. 3. http://www.dolby.com/us/en/consumer/technology/movie/dolby-atmos.html (IMHO, Dolby won't participate in the MPEG standardization process. And even if, Dolby Atmos seems to be finished.) The current situation at MPEG: http://www.itu.int/en/ITU-T/studygroups/com16/video/Pages/jctvc.aspx Next meetings: * Geneva, Switzerland, October
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
Very interesting post following discussion. I've actually been added very recently to the IST/37 committee, which apparently is a close relative to the MPEG one. However, I've not talked to any other members so far and I'm not sure how all this stuff works just yet! In other news, I spent a bit of time last year putting together a C API for object streaming etc (including Ambisonics). Hopefully it roughly captures the suggestions/requirements below. This project is now in a state where there's a fairly short API that seems to work and a basic SDK which provides some basic reference tools like a simple stereo renderer, lossless file format and network streaming. However, this isn't part of the API/Spec itself - the intent is that the C API should be independent of actual rendering/stream/persistence formats (although a reference is provided), so would hopefully play nice with Atmos/MDA. That said, I've not seen a *technical* spec for either of these yet, so there's a fair bit of guesswork happening. Certainly what's there now seems to work well for me, so far. :-/ The provisional spec has been bounced off a few folk but I've not heard much back (though I also had some email problems at a similar time). I'm wondering about releasing the API and SDK using some kind of open source license. Anyway - if folk are interested in more detail, please get in touch off-list! Best wishes, --Richard -Original Message- From: sursound-boun...@music.vt.edu [mailto:sursound-boun...@music.vt.edu] On Behalf Of Stefan Schreiber Sent: 06 January 2013 02:00 To: Surround Sound discussion group Subject: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style... Dear colleagues... I would like to remember everybody interested or already being involved that ITU/MPEG plan to define and issue some 3D audio standard (better: 3D audio standard framework) during this year. The 3D audio codec is meant to be part of the (wider) MPEG-H standard. This all makes a lot of sense, 'cos ;-) there is already some competition around: 1. Hamasaki 22.2, well known as (audio) part of former UHDTV (Super Hi-vision) proposals. 2. http://www.auro-3d.com/system/listening-formats (Note: a) The Auro-3D® Engine comprises: Auro Codec: The revolutionary codec that delivers native, discrete Auro-3D® content. Auro-Matic: The groundbreaking up-mixing algorithm that converts legacy content into the Auro- 3D® format. Auro-3D® Headphone: Like other audio configurations, similar results can be achieved with headphones that use binaural technology. b) Film, Broadcast, Gaming, Mobile, Automotive and Multimedia industries are all searching for a next generation sound format. With 3D Stereoscopic imagery becoming commonplace, the time is right for an audio experience that matches this increased level of fidelity. Sound in 3D is clearly the next step. 3. http://www.dolby.com/us/en/consumer/technology/movie/dolby-atmos.html (IMHO, Dolby won't participate in the MPEG standardization process. And even if, Dolby Atmos seems to be finished.) The current situation at MPEG: http://www.itu.int/en/ITU-T/studygroups/com16/video/Pages/jctvc.aspx Next meetings: * Geneva, Switzerland, October 2013 (tentative) * Vienna, Austria, 27 July - 2 August 2013 (tentative) * Incheon, Korea, 20-26 April 2013 (tentative) * Geneva, Switzerland, 14-23 January 2013 (tentative) During the next conference (January, Genève), the important HEVC codec should be technically finished. (Status: FDIS, for Final Draft International Standard) There will also be issued a final call for an 3D audio codec: At the 102nd MPEG meeting MPEG has issued a Draft Call for Proposals (CfP) on 3D Audio Coding. (This was the last meeting, Shanghai, October 2012) MPEG-H 3D Audio is envisaged to provide a highly immersive audio experience to accompany the highly immersive experience provided by MPEG-H HEVC. Such an immersive listening experience will be realized by the rendering of a realistic and compelling 3D audio scene either by using a large number of loudspeakers, such as for 22.2 channel audio programs, or by using headphones supporting binauralization. Key issues to be addressed are a compact and bit-efficient representation of multi-channel audio programs and the ability to flexibly render an audio program to an arbitrary number of loudspeakers with arbitrary configurations. 3D Audio support via headphones is also a key capability in order to deliver an immersive experience for users of mobile devices. A final CfP will be issued at the 103rd meeting in January 2012, (they mean January 2013, of course...) with selection of technology from amongst the responses received at the 105th meeting in July 2013. This technology will form the basis for MPEG-H 3D Audio, the Audio part (Part 3) of the MPEG-H (ISO/IEC 23008) suite of technologies. Taken together, the
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
Michael Chapman wrote: The current situation at MPEG: http://www.itu.int/en/ITU-T/studygroups/com16/video/Pages/jctvc.aspx Next meetings: * Geneva, Switzerland, October 2013 (tentative) * Vienna, Austria, 27 July - 2 August 2013 (tentative) * Incheon, Korea, 20-26 April 2013 (tentative) * Geneva, Switzerland, 14-23 January 2013 (tentative) Possibly not relevant in these days of (relatively) cheap air travel, but: I am near Geneva, colleagues at Graz are near Vienna, _if_ physical presence is a factor. But this is just 'mechanics' ... and should not distract from the main thrust of Stefan's call ! Michael I think it would be a great idea if some people like you would show up, because others ARE there and won't take our case. After reading all this Auro-3D/Barco stuff: It really seems they have invented 3D audio, and I am scratching my head in despair... :-) Somebody should also tell them that decoding to binaural/motion compensated binaural is of course possible and probably available , because this is currently an important topic. (If you can play surround /3D audio on some of all these trillions of mobile devices, surround of any kind ain't be a niche.) Thanks for your posting, very good point... Stefan -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20130106/0fc485a6/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
OK, Stefan, I'll look at my diary ;-( But 1) January 14-23 is ten days ... it is alo both tentative and 'next' week; 2 How does all this tye in with the MPEG-H 3D Audio Workshop (see copied email below). Whether related, or not, it would seem worth involving Gregory Pallone. If Orange (aka France Telecom) have a commercial interest in ambisonics then we have an ally. Michael Stefan Schreiber wrote: Michael Chapman wrote: The current situation at MPEG: http://www.itu.int/en/ITU-T/studygroups/com16/video/Pages/jctvc.aspx Next meetings: * Geneva, Switzerland, October 2013 (tentative) * Vienna, Austria, 27 July - 2 August 2013 (tentative) * Incheon, Korea, 20-26 April 2013 (tentative) * Geneva, Switzerland, 14-23 January 2013 (tentative) Possibly not relevant in these days of (relatively) cheap air travel, but: I am near Geneva, colleagues at Graz are near Vienna, _if_ physical presence is a factor. But this is just 'mechanics' ... and should not distract from the main thrust of Stefan's call ! Michael I think it would be a great idea if some people like you would show up, because others ARE there and won't take our case. After reading all this Auro-3D/Barco stuff: It really seems they have invented 3D audio, and I am scratching my head in despair... :-) Somebody should also tell them that decoding to binaural/motion compensated binaural is of course possible and probably available , because this is currently an important topic. (If you can play surround /3D audio on some of all these trillions of mobile devices, surround of any kind ain't be a niche.) Thanks for your posting, very good point... Stefan Original Message Subject: [Sursound] Make HOA count From:gregory.pall...@orange.com Date:Thu, July 5, 2012 11:33 pm To: sursound@music.vt.edu sursound@music.vt.edu -- Hello, I'm new to this group (even if my colleague Jerome (Daniel) shares sometimes info about it) so I hope you will excuse my usage of this list for the following information and questions ... The MPEG audio group is about to start a standardization process in order to create a 3D audio codec. As 3D audio experts, you are welcome to assist freely to the MPEG-H 3D Audio Workshop in Stockholm on July the 18th (all details here: http://www.audioresearchlabs.com/mpeg-h-workshop/101-3D-AudioWorkshop.pdf) This codec should have the ability to flexibly render an audio program to an arbitrary number of loudspeakers with arbitrary configurations. I think it could be a good opportunity to make it also support HOA format (as input of the audio encoder, output of the audio decoder, or both), and not only classical multichannel formats such as 5.1, 7.1, 10.2, 22.2... In this context, could you please send an email before July 11th to hoamilit...@gmail.commailto:hoamilit...@gmail.com indicating in just several sentences: - if you support HOA format as an input of the future 3D audio encoder, and why (what use-cases?) - if you support HOA format as an output of the future 3D audio decoder, and why (what use-cases?) - please indicate also what is your point of view: content creator, capturing or rendering device manufacturer, researcher, developer ... Thank you for sharing this valuable information which should help in militating in favor of HOA, and sorry for people not interested in my message. Gregory PS: Don't hesitate to forward this message to people/organizations/companies who could also be interested in attending the workshop and/or helping to militate in favor of HOA. _ Ce message et ses pieces jointes peuvent contenir des informations confidentielles ou privilegiees et ne doivent donc pas etre diffuses, exploites ou copies sans autorisation. Si vous avez recu ce message par erreur, veuillez le signaler a l'expediteur et le detruire ainsi que les pieces jointes. Les messages electroniques etant susceptibles d'alteration, France Telecom - Orange decline toute responsabilite si ce message a ete altere, deforme ou falsifie. Merci. This message and its attachments may contain confidential or privileged information that may be protected by law; they should not be distributed, used or copied without authorisation. If you have received this email in error, please notify the sender and delete this message and its attachments. As emails may be altered, France Telecom - Orange is not liable for messages that have been modified, changed or falsified. Thank you. -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20120705/33b3eec8/attachment.html ___ Sursound mailing list
Re: [Sursound] A proposal for an Ambisonics based 3D audio codec, MPEG/ITU style...
Michael Chapman wrote: OK, Stefan, I'll look at my diary ;-( But 1) January 14-23 is ten days ... it is alo both tentative and 'next' week; 2 How does all this tye in with the MPEG-H 3D Audio Workshop (see copied email below). 1) I am sorry, the date for the MPEG meetings seem to differ. (The JCT/ITU HEVC meetings might have a different schedule, oops...) Here the current schedules: http://mpeg.chiariglione.org/meetings http://mpeg.chiariglione.org/meetings/103 Date: Monday, 21 January 2013 to Friday, 25 January 2013 Venue: CICG rue de Varembé 17 1211 Geneve Switzerland See also agenda: HEVC is session nr. 21-22, 3D Audio nr. 23. 2) I didn't want to confuse, but I gave an update to possible channel layouts. 10.2 is actually offtopic, 11.1 not? Mr. Pallone: Could you give some hint on which day/time the 3D audio session is scheduled? Thanks for the valuable feedback Stefan ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
