- Ietf-types - alvestrand.no

MPEG asks for MIME review for the MPEG21 file format
by Stephan Wenger 23 May '07

23 May '07

Folks, MPEG (ISO/IEC JTC1 SC29) sent us an liaison statement asking us to review their draft for a MIME registration of the MPEG-21 file format. I know nothing about the subject matter, but hope some of you could give them a hand. Please direct any technical questions to Save Singer of Apple, singer(a)apple.com. Below, please find what I believe they want to register. Their full liaison statement (in a bunch of word files) can be found here: https://datatracker.ietf.org/ public/liaisons.cgi, look for ISO/IEC JTC1 SC29, May 2007 Best regards, Stephan > MIME media type name: application > MIME subtype name: mp21 > Required parameters: none > Optional parameters: none > Encoding considerations: base64 IS generally preferred; files are > binary and should be transmitted without CR/LF conversion, 7-bit > stripping, etc. > Security considerations: It is possible to inject non-compliant > MPEG streams (Audio, Video, and Systems) in the MP21 file to > overload the receiver/decoder's buffers. This might compromise the > functionality of the receiver or even crash it. > An MP21 file supports the storage of stream types, including > commands that are executed on the terminal such as Digital Item > Methods based on ECMASCRIPT for which also bindings to Java(TM) and > C++ exists. It is possible to use one or more of the above in a > manner non-compliant to MPEG to crash the receiver or temporarily > make it unavailable. > Authentication mechanisms can be used to validate of the sender and > the data to prevent security problems due to non-compliant > malignant MP21 files. > Interoperability considerations: A number of interoperating > implementations exist within the ISO/IEC 21000 community, and that > community has reference software for reading and writing the file > format. > Published specification: ISO/IEC 21000-9:2005 > Applications which use this media type: Multimedia > Additional information: > Magic number(s): none > > File extension(s): mp21 and mpg21 are both declared at http:// > pitch.nist.gov/nics/ and http://filext.com/ > > Macintosh File Type Code(s): mp21 is registered with Apple. > > Person & email address to contact for further information: David > Singer, singer(a)apple.com > Intended usage: COMMON > Author/Change controller: David Singer, ISO/IEC 21000 file format > chair

9 19

RE: MPEG asks for MIME review for the MPEG21 file format
by Larry Masinter 23 May '07

23 May '07

I'm really sorry to have opened this rat-hole on multiple mailing lists. I suggest moving the discussion of the hypothetical potential future possible proposals from the W3C XML efficient encoding group --- if you want to continue it at all --- to ietf-xml-mime(a)imc.org (I think that's the most appropriate) and removing any other cc's. Thanks, Larry

1 0

Re: MPEG asks for MIME review for the MPEG21 file format
by Graham Klyne 21 May '07

21 May '07

Chris Lilley wrote: > On Monday, May 21, 2007, 11:13:58 AM, Graham wrote: > GK> For clarification: this would be the case only when a suitable MIME > GK> content-transfer-encoding header is applied, n'est pas? > > If its compressed on the fly, yes. If its stored compressed on the server, then Content-Encoding is used. Ah, I hadn't considered Content-encoding here. I note that this header is defined by RFC2616 and registered only for use with HTTP (http://www.iana.org/assignments/message-headers/perm-headers.html) which suggests that it is defined only as part of an HTTP protocol transfer. #g (being rather language-lawyer-ish at this point?) -- Graham Klyne For email: http://www.ninebynine.org/#Contact

1 0

Re: MPEG asks for MIME review for the MPEG21 file format
by Graham Klyne 21 May '07

21 May '07

Chris Lilley wrote: > On Friday, May 18, 2007, 5:27:52 PM, Dave wrote: > > (I'm snipping the parts already covered by Martin) > > DS> Is a ZIP compressed XML file servable under a +xml MIME type? > DS> "encoding='zipped Shift_JIS'"? > > I suspect you mean gzip, which is a compression method; zip is an archive format (often compressed internally). > > If you started with foo.xml in Shift_JIS, the encoding declaration would say just that. If you then make foo.xml.gz the encoding declaration (when decompressed) says exactly the same thing. The fact that is been gzipped is conveyed out of band, in the http headers: > > Content-Encoding: gzip > > There is scope for confusion, since XML uses 'encoding' for 'character encoding' (although that's a big advance on calling it 'charset'). HTTP uses content-encoding. The two uses of the concept 'encoding' occur at different levels in the stack. > > In consequence, using gzip content-encoding is compatible with +xml media types. For clarification: this would be the case only when a suitable MIME content-transfer-encoding header is applied, n'est pas? Otherwise such added encoding/decoding could be applied lower in the stack and not visible at the level of the MIME object. #g -- Graham Klyne For email: http://www.ninebynine.org/#Contact

1 0

RE: Registrtion of MIME media type audio/aptX
by Greg Massey 21 May '07

21 May '07

Hi Magnus, Thanks for the clarification, being new to this I realise that I am making mistakes here. Apologies. Regards Greg -----Original Message----- From: Magnus Westerlund [mailto:magnus.westerlund@ericsson.com] Sent: 21 May 2007 09:39 To: Colin Perkins Cc: Greg Massey; ietf-types(a)iana.org Subject: Re: Registrtion of MIME media type audio/aptX Colin Perkins skrev: > Greg, > > We have previously discussed bringing this work to the IETF AVT > working > group. I would strongly suggest that you do so, submitting an > Internet-Draft for your RTP Payload Format, and allowing the working > group to provide advice. As they stand, these draft registrations fail > to address the issues (correct media parameters, SDP, conformance to RFC > 4855, etc.) in a number of ways. > And to further clarify. You are not allowed to register audio/aptx (in the standards tree) unless there is a standards document (RFC or other recognized SDO) defining payload format and codecs. If that isn't available, I would recommend registering them in the vendor tree, i.e. audio/vnd.apt.X Cheers Magnus Westerlund IETF Transport Area Director & TSVWG Chair ---------------------------------------------------------------------- Multimedia Technologies, Ericsson Research EAB/TVM/M ---------------------------------------------------------------------- Ericsson AB | Phone +46 8 4048287 Torshamsgatan 23 | Fax +46 8 7575550 S-164 80 Stockholm, Sweden | mailto: magnus.westerlund(a)ericsson.com ----------------------------------------------------------------------

1 0

Registrtion of MIME media type audio/aptX
by Greg Massey 21 May '07

21 May '07

MIME media type name: audio MIME subtype name: aptX Required parameters: rate/Channels The RTP timestamp clock rate, which is equal to the sampling rate. The typical rate is 48000, but other rates may be specified. Optional parameters: AudioMode/Aux Audio Mode: Stereo/Mono/DualMono (S/M/DM) Aux: Auxiliary data stream (AuxOn/AuxOff) Encoding considerations: This type is only defined for transfer via RTP [RFC 3550]. Security considerations: See Section 5 of RFC 3555 Interoperability considerations: none Published specification: Applications which use this media type: Audio and video streaming and conferencing tools. Additional information: none Person & email address to contact for further information: Gregory Massey <gmassey(a)aptx.com> Intended usage: COMMON Author/Change controller: Gregory Massey Gregory Massey Chief Technical Officer Audio Processing Technology Tel: +44-28-9037 1110 Fax: +44-28-9037 1137 Mob: +44 784110 2975 Email: gmassey(a)aptx.com Website: www.aptx.com <http://www.aptx.com/content.asp?site=1&page=50>

4 3

Registration of MIME media type audio/aptXLive
by Greg Massey 15 May '07

15 May '07

MIME media type name: audio MIME subtype name: aptXLive Required parameters: rate/Channels The RTP timestamp clock rate, which is equal to the sampling rate. The typical rate is 48000, but other rates may be specified. Optional parameters: AudioMode/Aux/Scale Audio Mode: Stereo/Mono Aux: Auxiliary data stream (AuxOn/AuxOff) Scale: Scale factors for aptX-Live algorithm (S20/S25/S30) Encoding considerations: This type is only defined for transfer via RTP [RFC 3550]. Security considerations: See Section 5 of RFC 3555 Interoperability considerations: none Published specification: Applications which use this media type: Audio and video streaming and conferencing tools. Additional information: none Person & email address to contact for further information: Gregory Massey <gmassey(a)aptx.com> Intended usage: COMMON Author/Change controller: Gregory Massey Gregory Massey Chief Technical Officer Audio Processing Technology Tel: +44-28-9037 1110 Fax: +44-28-9037 1137 Mob: +44 784110 2975 Email: gmassey(a)aptx.com Website: www.aptx.com <http://www.aptx.com/content.asp?site=1&page=50>

1 0

Registration of MIME media type audio/EaptX24
by Greg Massey 15 May '07

15 May '07

MIME media type name: audio MIME subtype name: EaptX24 Required parameters: rate/Channels The RTP timestamp clock rate, which is equal to the sampling rate. The typical rate is 48000, but other rates may be specified. Optional parameters: AudioMode/Aux/ Audio Mode: Stereo/Mono/DualMono Aux: Auxiliary data stream (AuxOn/AuxOff) Encoding considerations: This type is only defined for transfer via RTP [RFC 3550]. Security considerations: See Section 5 of RFC 3555 Interoperability considerations: none Published specification: Applications which use this media type: Audio and video streaming and conferencing tools. Additional information: none Person & email address to contact for further information: Gregory Massey <gmassey(a)aptx.com> Intended usage: COMMON Author/Change controller: Gregory Massey Gregory Massey Chief Technical Officer Audio Processing Technology Tel: +44-28-9037 1110 Fax: +44-28-9037 1137 Mob: +44 784110 2975 Email: gmassey(a)aptx.com Website: www.aptx.com <http://www.aptx.com/content.asp?site=1&page=50>

1 0

Registration of MIME media type audio/EaptX16
by Greg Massey 15 May '07

15 May '07

MIME media type name: audio MIME subtype name: EaptX16 Required parameters: rate, channels The RTP timestamp clock rate, which is equal to the sampling rate. The typical rate is 48000, but other rates may be specified. Default for channels is 2 (Stereo) Optional parameters: AudioMode/Aux Audio Mode: Stereo/Mono/DualMono (S/M/DM) Aux: Auxiliary data stream (AuxOn/AuxOff) Encoding considerations: This type is only defined for transfer via RTP [RFC 3550]. Security considerations: See Section 5 of RFC 3555 Interoperability considerations: none Published specification: Applications which use this media type: Audio and video streaming and conferencing tools. Additional information: none Person & email address to contact for further information: Gregory Massey <gmassey(a)aptx.com> Intended usage: COMMON Author/Change controller: Gregory Massey Gregory Massey Chief Technical Officer Audio Processing Technology Tel: +44-28-9037 1110 Fax: +44-28-9037 1137 Mob: +44 784110 2975 Email: gmassey(a)aptx.com Website: www.aptx.com <http://www.aptx.com/content.asp?site=1&page=50>

1 0

Preliminary Community Review: text/json
by Douglas Crockford 15 Apr '07

15 Apr '07

This is notice of a potential media type registration. The details may be found here: http://www.ietf.org/internet-drafts/draft-crockford-jsonorg-json-02.txt

10 11