Commit c0db3e77 authored by lu_zero's avatar lu_zero

Draft update

svn path=/trunk/vorbis/; revision=13163
parent 1a40dacb
......@@ -88,7 +88,7 @@ Table of Contents
7.1. Mapping Media Type Parameters into SDP . . . . . . . . . . 20
7.1.1. SDP Example . . . . . . . . . . . . . . . . . . . . . 21
7.2. Usage with the SDP Offer/Answer Model . . . . . . . . . . 21
8. Congestion Control . . . . . . . . . . . . . . . . . . . . . . 21
8. Congestion Control . . . . . . . . . . . . . . . . . . . . . . 22
9. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
9.1. Stream Radio . . . . . . . . . . . . . . . . . . . . . . . 22
10. Security Considerations . . . . . . . . . . . . . . . . . . . 23
......@@ -125,7 +125,7 @@ Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
quadraphonic, 5.1, ambisonic, or up to 255 discrete channels).
Vorbis encoded audio is generally encapsulated within an Ogg format
bitstream [10], which provides framing and synchronization. For the
bitstream [11], which provides framing and synchronization. For the
purposes of RTP transport, this layer is unnecessary, and so raw
Vorbis packets are used in the payload.
......@@ -209,7 +209,7 @@ Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
Marker (M): 1 bit
Set to zero. Audio silence suppression not used. This conforms to
section 4.1 of [12].
section 4.1 of [13].
Payload Type (PT): 7 bits
......@@ -304,7 +304,7 @@ Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
Raw Vorbis packets are currently unbounded in length, application
profiles will likely define a practical limit. Typical Vorbis packet
sizes range from very small (2-3 bytes) to quite large (8-12
kilobytes). The reference implementation [11] typically produces
kilobytes). The reference implementation [12] typically produces
packets less than ~800 bytes, except for the setup header packets
which are ~4-12 kilobytes. Within an RTP context, to avoid
fragmentation, the Vorbis data packet size SHOULD be kept
......@@ -322,7 +322,7 @@ Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
Each Vorbis payload packet starts with a two octet length header,
which is used to represent the size in bytes of the following data
payload, followed by the raw Vorbis data padded to the nearest byte
boundary, as explained by the vorbis specification [12]. The length
boundary, as explained by the vorbis specification [13]. The length
value is stored as network byte order integer.
For payloads which consist of multiple Vorbis packets the payload
......@@ -346,7 +346,7 @@ Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
in temporal order.
Channel mapping of the audio is in accordance with the Vorbis I
Specification [12].
Specification [13].
2.4. Example RTP Packet
......@@ -410,7 +410,7 @@ Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
blocks of information are often referred to collectively as the
"codebooks" for a Vorbis stream, and are nominally included as
special "header" packets at the start of the compressed data. In
addition, the Vorbis I specification [12] requires the presence of a
addition, the Vorbis I specification [13] requires the presence of a
comment header packet which gives simple metadata about the stream,
but this information is not required for decoding the frame sequence.
......@@ -463,7 +463,7 @@ Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
A Vorbis Packed Configuration is indicated with the Vorbis Data Type
field set to 1. Of the three headers defined in the Vorbis I
specification [12], the identification and the setup MUST be packed
specification [13], the identification and the setup MUST be packed
as they are, while the comment header MAY be replaced with a dummy
one. The packed configuration follows a generic way to store xiph
codec configurations: The first field stores the number of the
......@@ -664,7 +664,7 @@ Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
and so on. These metadata messages are not intended to be fully
descriptive but to offer basic track/song information. Clients MAY
ignore it completely. The details on the format of the comments can
be found in the Vorbis documentation [12].
be found in the Vorbis documentation [13].
......@@ -711,7 +711,7 @@ Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
in the RTP packet with as many Vorbis packets as will fit, up to a
maximum of 15, except when such bundling would exceed an
application's desired transmission latency. Path MTU is detailed in
[5] and [6].
[6] and [7].
A fragmented packet has a zero in the last four bits of the payload
header. The first fragment will set the Fragment type to 1. Each
......@@ -917,31 +917,31 @@ Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
possible values are: inline, in_band, out_band, MAY be included
multiple times
configuration: the base64 [8] representation of the Packed
configuration: the base64 [9] representation of the Packed
Headers (Section 3.2.1). It MUST follow the associated
delivery-method parameter ("inline").
Optional parameters:
configuration-uri: the URI of the configuration headers in case
of out of band transmission. In the form of
"protocol://path/to/resource/". Depending on the specific
configuration-uri: the URI [4] of the configuration headers in
case of out of band transmission. In the form of
"protocol://path/to/resource/", depending on the specific
method, a single configuration packet could be retrived by its
number, or multiple packets could be aggregated in a single
stream. Such aggregates MAY be compressed using either bzip2
[15] or gzip [13]. A sha1 [9] checksum MAY be provided for
aggregates. In this latter case the URI will end with the
Ident number, or multiple packets could be aggregated in a
single stream. Such aggregates MAY be compressed using either
bzip2 [16] or gzip [14]. A sha1 [10] checksum MAY be provided
for aggregates. In this latter case the URI will end with the
aggregate name, followed by its compressed extension if
applies, a "!" and the base64 [8] representation of the
applies, a "!" and the base64 [9] representation of the
sha1hash of the above mentioned compressed aggregated as in:
"protocol://path/to/resource/aggregated.bz2!sha1hash". The
trailing '/' discriminates which of two methods are in use. It
MUST follow the associated delivery method parameter (either
"in_band" or "out_band").
trailing '/' discriminates which of two methods are in use.
The configuration-uri MUST follow the associated delivery
method parameter ("out_band"). Non hierarchical protocols and
protocols using for special purposes the '!' separator MAY
point just to a resource aggregate using their specific syntax.
Encoding considerations:
This media type is framed and contains binary data.
......@@ -953,6 +953,10 @@ Barbato Expires December 1, 2007 [Page 17]
Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
Encoding considerations:
This media type is framed and contains binary data.
Security considerations:
See Section 10 of RFC XXXX.
......@@ -995,10 +999,6 @@ Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
Luca Barbato
Change controller:
IETF AVT Working Group delegated from the IESG
......@@ -1009,6 +1009,11 @@ Barbato Expires December 1, 2007 [Page 18]
Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
Change controller:
IETF AVT Working Group delegated from the IESG
6.1. Packed Headers IANA Considerations
The following IANA considerations MUST only be applied to the packed
......@@ -1051,11 +1056,6 @@ Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
None
Person & email address to contact for further information:
Luca Barbato: <lu_zero@gentoo.org>
IETF Audio/Video Transport Working Group
......@@ -1065,6 +1065,11 @@ Barbato Expires December 1, 2007 [Page 19]
Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
Person & email address to contact for further information:
Luca Barbato: <lu_zero@gentoo.org>
IETF Audio/Video Transport Working Group
Intended usage: COMMON
Restriction on usage:
......@@ -1084,13 +1089,13 @@ Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
The following paragraphs defines the mapping of the parameters
described in the IANA considerations section and their usage in the
Offer/Answer Model [7].
Offer/Answer Model [8].
7.1. Mapping Media Type Parameters into SDP
The information carried in the Media Type media type specification
has a specific mapping to fields in the Session Description Protocol
(SDP) [4], which is commonly used to describe RTP sessions. When SDP
(SDP) [5], which is commonly used to describe RTP sessions. When SDP
is used to specify sessions the mapping are as follows:
o The type name ("audio") goes in SDP "m=" as the media name.
......@@ -1109,11 +1114,6 @@ Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
included in the SDP "a=fmtp" attribute and MUST follow the
delivery-method that applies.
If the stream comprises chained Vorbis files and all of them are
known in advance, the Configuration Packet for each file SHOULD be
passed to the client using the configuration attribute.
Barbato Expires December 1, 2007 [Page 20]
......@@ -1121,6 +1121,10 @@ Barbato Expires December 1, 2007 [Page 20]
Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
If the stream comprises chained Vorbis files and all of them are
known in advance, the Configuration Packet for each file SHOULD be
passed to the client using the configuration attribute.
The URI specified in the configuration-uri attribute MUST point to a
location where all of the Configuration Packets needed for the life
of the session reside.
......@@ -1136,12 +1140,12 @@ Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
configuration packet is inlined in the sdp, other configurations
could be fetched at any time from the first provided uri using or all
the known configuration could be downloaded using the second uri.
The inline base64 [8] configuration string is omitted because of the
The inline base64 [9] configuration string is omitted because of the
length.
c=IN IP4 192.0.2.1
m=audio RTP/AVP 98
a=rtpmap:98 vorbis/44100/2
a=fmtp:98 delivery-method=in_band; configuration=base64string;
a=fmtp:98 delivery-method=inline; configuration=base64string;
delivery-method=out_band;
configuration-uri=rtsp://path/to/the/resource; delivery-
method=out_band; configuration-uri=http://another/path/to/
......@@ -1160,16 +1164,12 @@ Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
The only paramenter negotiable is the delivery method. All the
others are declarative: the offer, as described in An Offer/Answer
Model Session Description Protocol [7], may contain a large number of
Model Session Description Protocol [8], may contain a large number of
delivery methods per single fmtp attribute, the answerer MUST remove
every delivery-method and configuration-uri not supported. All the
parameters MUST not be altered on answer otherwise.
8. Congestion Control
Vorbis clients SHOULD send regular receiver reports detailing
Barbato Expires December 1, 2007 [Page 21]
......@@ -1177,6 +1177,9 @@ Barbato Expires December 1, 2007 [Page 21]
Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
8. Congestion Control
Vorbis clients SHOULD send regular receiver reports detailing
congestion. A mechanism for dynamically downgrading the stream,
known as bitrate peeling, will allow for a graceful backing off of
the stream bitrate. This feature is not available at present so an
......@@ -1212,7 +1215,7 @@ Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
The client could choose to fetch the Configuration from the alternate
source as soon as it discovers a Configuration packet got lost in-
band or use selective retransmission [14], if the server supports the
band or use selective retransmission [15], if the server supports the
feature.
A serverside optimization would be to keep an hash list of the
......@@ -1225,9 +1228,6 @@ Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
Barbato Expires December 1, 2007 [Page 22]
Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
......@@ -1277,10 +1277,10 @@ Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
[3] Schulzrinne, H. and S. Casner, "RTP Profile for Audio and Video
Conferences with Minimal Control.", RFC 3551.
[4] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session
Description Protocol", RFC 4566, July 2006.
[4] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
Resource Identifier (URI): Generic Syntax", RFC 3986.
[5] Mogul, J. and S. Deering, "Path MTU discovery", RFC 1191,
[5] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session
......@@ -1289,38 +1289,41 @@ Barbato Expires December 1, 2007 [Page 23]
Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
Description Protocol", RFC 4566, July 2006.
[6] Mogul, J. and S. Deering, "Path MTU discovery", RFC 1191,
November 1990.
[6] McCann et al., J., "Path MTU Discovery for IP version 6",
[7] McCann et al., J., "Path MTU Discovery for IP version 6",
RFC 1981.
[7] Rosenberg, J. and H. Schulzrinne, "An Offer/Answer Model with
[8] Rosenberg, J. and H. Schulzrinne, "An Offer/Answer Model with
Session Description Protocol (SDP)", RFC 3264.
[8] Josefsson, S., "The Base16, Base32, and Base64 Data Encodings",
[9] Josefsson, S., "The Base16, Base32, and Base64 Data Encodings",
RFC 3548.
[9] National Institute of Standards and Technology, "Secure Hash
[10] National Institute of Standards and Technology, "Secure Hash
Standard", May 1993.
12.2. Informative References
[10] Pfeiffer, S., "The Ogg Encapsulation Format Version 0",
[11] Pfeiffer, S., "The Ogg Encapsulation Format Version 0",
RFC 3533.
[11] "libvorbis: Available from the Xiph website,
[12] "libvorbis: Available from the Xiph website,
http://www.xiph.org".
[12] "Ogg Vorbis I specification: Codec setup and packet decode.
[13] "Ogg Vorbis I specification: Codec setup and packet decode.
Available from the Xiph website, http://www.xiph.org".
[13] Deutsch, P., "GZIP file format specification version 4.3",
[14] Deutsch, P., "GZIP file format specification version 4.3",
RFC 1952.
[14] Friedman, T., Caceres, R., and A. Clark, "RTP Control Protocol
[15] Friedman, T., Caceres, R., and A. Clark, "RTP Control Protocol
Extended Reports (RTCP XR)", RFC 3611, November 2003.
[15] Seward, J., "libbz2 and bzip2".
[16] Seward, J., "libbz2 and bzip2".
Author's Address
......@@ -1337,9 +1340,6 @@ Author's Address
Barbato Expires December 1, 2007 [Page 24]
Internet-Draft draft-ietf-avt-rtp-vorbis-05 May 2007
......
......@@ -821,18 +821,20 @@ Configuration packet with the result detailed in the <xref target="Loss of Confi
<vspace blankLines="1" />
<list style="hanging">
<t hangText="configuration-uri:"> the URI of the configuration headers in case
of out of band transmission. In the form of "protocol://path/to/resource/".
Depending on the specific method, a single configuration packet could be
retrived by its number, or multiple packets could be aggregated in a single
stream. Such aggregates MAY be compressed using either
<t hangText="configuration-uri:"> the <xref target="rfc3986">URI</xref> of
the configuration headers in case of out of band transmission.
In the form of "protocol://path/to/resource/", depending on the specific
method, a single configuration packet could be retrived by its Ident number, or
multiple packets could be aggregated in a single stream.
Such aggregates MAY be compressed using either
<xref target="BZ2">bzip2</xref> or <xref target="rfc1952">gzip</xref>.
A <xref target="FIPS180">sha1</xref> checksum MAY be provided for aggregates.
In this latter case the URI will end with the aggregate name, followed by its
compressed extension if applies, a "!" and the <xref target="rfc3548">base64</xref> representation of the sha1hash of the above mentioned compressed aggregated
as in: "protocol://path/to/resource/aggregated.bz2!sha1hash".
The trailing '/' discriminates which of two methods are in use.
It MUST follow the associated delivery method parameter (either "in_band" or "out_band").
The configuration-uri MUST follow the associated delivery method parameter ("out_band").
Non hierarchical protocols and protocols using for special purposes the '!' separator MAY point just to a resource aggregate using their specific syntax.
</t>
</list>
</t>
......@@ -1249,6 +1251,20 @@ Ridolfo, Francesco Varano, Giampaolo Mancini, Dario Gallucci, Juan Carlos De Mar
<seriesInfo name="RFC" value="3551" />
</reference>
<reference anchor='rfc3986'>
<front>
<title abbrev='URI Generic Syntax'>Uniform Resource Identifier (URI): Generic Syntax</title>
<author initials='T.' surname='Berners-Lee' fullname='Tim Berners-Lee'>
</author>
<author initials='R.' surname='Fielding' fullname='Roy T. Fielding'>
</author>
<author initials='L.' surname='Masinter' fullname='Larry Masinter'>
</author>
</front>
<date year='2005' month='January' />
<seriesInfo name='RFC' value='3986' />
</reference>
<reference anchor='rfc4566'>
<front>
......
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