[xiph-commits] r13558 - trunk/vorbis/doc
lu_zero at svn.xiph.org
lu_zero at svn.xiph.org
Thu Aug 16 01:54:30 PDT 2007
Author: lu_zero
Date: 2007-08-16 01:54:30 -0700 (Thu, 16 Aug 2007)
New Revision: 13558
Modified:
trunk/vorbis/doc/draft-ietf-avt-rtp-vorbis-06.txt
trunk/vorbis/doc/draft-ietf-avt-rtp-vorbis-06.xml
Log:
Simplify configuration-uri handling
Modified: trunk/vorbis/doc/draft-ietf-avt-rtp-vorbis-06.txt
===================================================================
--- trunk/vorbis/doc/draft-ietf-avt-rtp-vorbis-06.txt 2007-08-16 08:34:22 UTC (rev 13557)
+++ trunk/vorbis/doc/draft-ietf-avt-rtp-vorbis-06.txt 2007-08-16 08:54:30 UTC (rev 13558)
@@ -83,12 +83,12 @@
5.1. Example Fragmented Vorbis Packet . . . . . . . . . . . . . 14
5.2. Packet Loss . . . . . . . . . . . . . . . . . . . . . . . 16
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17
- 6.1. Packed Headers IANA Considerations . . . . . . . . . . . . 19
+ 6.1. Packed Headers IANA Considerations . . . . . . . . . . . . 18
7. SDP related considerations . . . . . . . . . . . . . . . . . . 20
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 . . . . . . . . . . . . . . . . . . . . . . 22
+ 8. Congestion Control . . . . . . . . . . . . . . . . . . . . . . 21
9. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
9.1. Stream Radio . . . . . . . . . . . . . . . . . . . . . . . 22
10. Security Considerations . . . . . . . . . . . . . . . . . . . 23
@@ -125,7 +125,7 @@
quadraphonic, 5.1, ambisonic, or up to 255 discrete channels).
Vorbis encoded audio is generally encapsulated within an Ogg format
- bitstream [14], 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 @@
Marker (M): 1 bit
Set to zero. Audio silence suppression not used. This conforms to
- section 4.1 of [12].
+ section 4.1 of [10].
Payload Type (PT): 7 bits
@@ -304,7 +304,7 @@
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 [15] 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 @@
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 [10]. The length
value is stored as network byte order integer.
For payloads which consist of multiple Vorbis packets the payload
@@ -346,7 +346,7 @@
in temporal order.
Channel mapping of the audio is in accordance with the Vorbis I
- Specification [12].
+ Specification [10].
2.4. Example RTP Packet
@@ -410,7 +410,7 @@
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 [10] 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.
@@ -457,13 +457,13 @@
The Packed Configuration (Section 3.1.1) Payload is sent in-band with
the packet type bits set to match the Vorbis Data Type. Clients MUST
be capable of dealing with fragmentation and periodic re-transmission
- of [17] the configuration headers.
+ of [14] the configuration headers.
3.1.1. Packed Configuration
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 [10], 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 @@
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 [10].
@@ -928,43 +928,31 @@
"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
- bzip2 [11] or gzip [13]. 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 [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.
- 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.
+ single stream. Non hierarchical protocols MAY point to a
+ resource using their specific syntax.
+ Encoding considerations:
+ This media type is framed and contains binary data.
+ Security considerations:
+ See Section 10 of RFC XXXX.
+ Interoperability considerations:
+ None
-Barbato Expires December 27, 2007 [Page 17]
-
-Internet-Draft draft-ietf-avt-rtp-vorbis-06 Jun 2007
- Encoding considerations:
- This media type is framed and contains binary data.
- Security considerations:
+Barbato Expires December 27, 2007 [Page 17]
+
+Internet-Draft draft-ietf-avt-rtp-vorbis-06 Jun 2007
- See Section 10 of RFC XXXX.
- Interoperability considerations:
-
- None
-
Published specification:
RFC XXXX [RFC Editor: please replace by the RFC number of this
@@ -999,26 +987,28 @@
Luca Barbato
+ 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
+ headers.
-Barbato Expires December 27, 2007 [Page 18]
-
-Internet-Draft draft-ietf-avt-rtp-vorbis-06 Jun 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
- headers.
+Barbato Expires December 27, 2007 [Page 18]
+
+Internet-Draft draft-ietf-avt-rtp-vorbis-06 Jun 2007
+
+
Type name: audio
Subtype name: vorbis-config
@@ -1056,22 +1046,25 @@
None
+ Person & email address to contact for further information:
+ Luca Barbato: <lu_zero at gentoo.org>
+ IETF Audio/Video Transport Working Group
+ Intended usage: COMMON
+
+
+
+
+
+
Barbato Expires December 27, 2007 [Page 19]
Internet-Draft draft-ietf-avt-rtp-vorbis-06 Jun 2007
- Person & email address to contact for further information:
-
- Luca Barbato: <lu_zero at gentoo.org>
- IETF Audio/Video Transport Working Group
-
- Intended usage: COMMON
-
Restriction on usage:
This media type doesn't depend on the transport.
@@ -1114,19 +1107,20 @@
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.
+ The URI specified in the configuration-uri attribute MUST point to a
+ location where all of the Configuration Packets needed for the life
+
+
Barbato Expires December 27, 2007 [Page 20]
Internet-Draft draft-ietf-avt-rtp-vorbis-06 Jun 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.
The port value is specified by the server application bound to the
@@ -1171,16 +1165,18 @@
parameters MUST not be altered on answer otherwise.
+8. Congestion Control
+ Vorbis clients SHOULD send regular receiver reports detailing
+ congestion. A mechanism for dynamically downgrading the stream,
+
+
+
Barbato Expires December 27, 2007 [Page 21]
Internet-Draft draft-ietf-avt-rtp-vorbis-06 Jun 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
alternative would be to redirect the client to a lower bitrate stream
@@ -1215,7 +1211,7 @@
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 [16], if the server supports the
+ band or use selective retransmission [13], if the server supports the
feature.
A serverside optimization would be to keep an hash list of the
@@ -1228,6 +1224,10 @@
+
+
+
+
Barbato Expires December 27, 2007 [Page 22]
Internet-Draft draft-ietf-avt-rtp-vorbis-06 Jun 2007
@@ -1303,29 +1303,21 @@
[9] Josefsson, S., "The Base16, Base32, and Base64 Data Encodings",
RFC 3548.
- [10] National Institute of Standards and Technology, "Secure Hash
- Standard", May 1993.
-
- [11] Seward, J., "libbz2 and bzip2".
-
- [12] "Ogg Vorbis I specification: Codec setup and packet decode.
+ [10] "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",
- RFC 1952.
-
12.2. Informative References
- [14] Pfeiffer, S., "The Ogg Encapsulation Format Version 0",
+ [11] Pfeiffer, S., "The Ogg Encapsulation Format Version 0",
RFC 3533.
- [15] "libvorbis: Available from the Xiph website,
+ [12] "libvorbis: Available from the Xiph website,
http://www.xiph.org".
- [16] Friedman, T., Caceres, R., and A. Clark, "RTP Control Protocol
+ [13] Friedman, T., Caceres, R., and A. Clark, "RTP Control Protocol
Extended Reports (RTCP XR)", RFC 3611, November 2003.
- [17] Rey, J., Leon, D., Miyazaki, A., Varsa, V., and R. Hakenberg,
+ [14] Rey, J., Leon, D., Miyazaki, A., Varsa, V., and R. Hakenberg,
"RTP Retransmission Payload Format", RFC 4588, July 2006.
@@ -1340,6 +1332,14 @@
+
+
+
+
+
+
+
+
Barbato Expires December 27, 2007 [Page 24]
Internet-Draft draft-ietf-avt-rtp-vorbis-06 Jun 2007
Modified: trunk/vorbis/doc/draft-ietf-avt-rtp-vorbis-06.xml
===================================================================
--- trunk/vorbis/doc/draft-ietf-avt-rtp-vorbis-06.xml 2007-08-16 08:34:22 UTC (rev 13557)
+++ trunk/vorbis/doc/draft-ietf-avt-rtp-vorbis-06.xml 2007-08-16 08:54:30 UTC (rev 13558)
@@ -826,15 +826,8 @@
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.
-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.
+Non hierarchical protocols MAY point to a resource using their specific
+syntax.
</t>
</list>
</t>
@@ -1266,7 +1259,6 @@
</reference>
<reference anchor='rfc4566'>
-
<front>
<title>SDP: Session Description Protocol</title>
<author initials='M.' surname='Handley' fullname='M. Handley'>
@@ -1277,13 +1269,11 @@
<organization /></author>
<date year='2006' month='July' />
</front>
-
<seriesInfo name='RFC' value='4566' />
<format type='TXT' octets='108820' target='ftp://ftp.isi.edu/in-notes/rfc4566.txt' />
</reference>
<reference anchor='rfc1191'>
-
<front>
<title>Path MTU discovery</title>
<author initials='J.' surname='Mogul' fullname='Jeffrey Mogul'>
@@ -1296,7 +1286,6 @@
<email>deering at xerox.com</email></address></author>
<date year='1990' day='1' month='November' />
</front>
-
<seriesInfo name='RFC' value='1191' />
<format type='TXT' octets='47936' target='ftp://ftp.isi.edu/in-notes/rfc1191.txt' />
</reference>
@@ -1325,34 +1314,13 @@
</front>
<seriesInfo name="RFC" value="3548" />
</reference>
-<reference anchor="FIPS180">
-<front>
-<title>Secure Hash Standard</title>
-<author>
-<organization>National Institute of Standards and Technology</organization>
-</author>
-<date month="May" year="1993"/>
-</front>
-</reference>
-<reference anchor="BZ2">
-<front>
-<title>libbz2 and bzip2</title>
-<author initials="J" surname="Seward" fullname="Julian Seward" />
-</front>
-</reference>
+
<reference anchor="vorbis-spec-ref">
<front>
<title>Ogg Vorbis I specification: Codec setup and packet decode. Available from the Xiph website, http://www.xiph.org</title>
</front>
-</reference>
-
-<reference anchor="rfc1952">
-<front>
-<title>GZIP file format specification version 4.3</title>
-<author initials="P" surname="Deutsch" fullname="L. Peter Deutsch"></author>
-</front>
-<seriesInfo name="RFC" value="1952" />
</reference>
+
</references>
<references title="Informative References">
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