[xiph-commits] r12364 - trunk/vorbis/doc
lu_zero at svn.xiph.org
lu_zero at svn.xiph.org
Sat Jan 20 10:39:36 PST 2007
Author: lu_zero
Date: 2007-01-20 10:39:33 -0800 (Sat, 20 Jan 2007)
New Revision: 12364
Modified:
trunk/vorbis/doc/draft-ietf-avt-rtp-vorbis-01.txt
trunk/vorbis/doc/draft-ietf-avt-rtp-vorbis-01.xml
Log:
Updates, pending review
Modified: trunk/vorbis/doc/draft-ietf-avt-rtp-vorbis-01.txt
===================================================================
--- trunk/vorbis/doc/draft-ietf-avt-rtp-vorbis-01.txt 2007-01-20 14:34:29 UTC (rev 12363)
+++ trunk/vorbis/doc/draft-ietf-avt-rtp-vorbis-01.txt 2007-01-20 18:39:33 UTC (rev 12364)
@@ -1,7 +1,6 @@
-
AVT Working Group L. Barbato
Internet-Draft Xiph.Org
Expires: December 18, 2006 June 16, 2006
@@ -37,7 +36,7 @@
Copyright Notice
- Copyright (C) The Internet Society (2006).
+ Copyright (C) The IETF Trust (2006).
Abstract
@@ -47,12 +46,12 @@
probability model, referred to as a codebook and other setup
information.
- Also included within the document are the necessary details for the
- use of Vorbis with MIME and Session Description Protocol (SDP).
+ Also included within this memo are media type registrations, and the
+ details necessary for the use of Vorbis with the Session Description
+ Protocol (SDP).
-
Barbato Expires December 18, 2006 [Page 1]
Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
@@ -77,26 +76,27 @@
3.1. In-band Header Transmission . . . . . . . . . . . . . . . 9
3.1.1. Packed Configuration . . . . . . . . . . . . . . . . . 9
3.2. Out of Band Transmission . . . . . . . . . . . . . . . . . 10
- 3.2.1. Packed Headers . . . . . . . . . . . . . . . . . . . . 10
+ 3.2.1. Packed Headers . . . . . . . . . . . . . . . . . . . . 11
3.3. Loss of Configuration Headers . . . . . . . . . . . . . . 13
4. Comment Headers . . . . . . . . . . . . . . . . . . . . . . . 13
5. Frame Packetization . . . . . . . . . . . . . . . . . . . . . 14
5.1. Example Fragmented Vorbis Packet . . . . . . . . . . . . . 15
5.2. Packet Loss . . . . . . . . . . . . . . . . . . . . . . . 17
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 18
- 6.1. Mapping MIME Parameters into SDP . . . . . . . . . . . . . 19
- 6.1.1. SDP Example . . . . . . . . . . . . . . . . . . . . . 20
- 6.2. Usage with the SDP Offer/Answer Model . . . . . . . . . . 21
- 7. Congestion Control . . . . . . . . . . . . . . . . . . . . . . 21
- 8. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
- 8.1. Stream Radio . . . . . . . . . . . . . . . . . . . . . . . 21
- 9. Security Considerations . . . . . . . . . . . . . . . . . . . 22
- 10. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 22
- 11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 23
- 11.1. Normative References . . . . . . . . . . . . . . . . . . . 23
- 11.2. Informative References . . . . . . . . . . . . . . . . . . 23
- Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 25
- Intellectual Property and Copyright Statements . . . . . . . . . . 26
+ 7. SDP related considerations . . . . . . . . . . . . . . . . . . 20
+ 7.1. Mapping MIME Parameters into SDP . . . . . . . . . . . . . 20
+ 7.1.1. SDP Example . . . . . . . . . . . . . . . . . . . . . 20
+ 7.2. Usage with the SDP Offer/Answer Model . . . . . . . . . . 21
+ 8. Congestion Control . . . . . . . . . . . . . . . . . . . . . . 21
+ 9. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
+ 9.1. Stream Radio . . . . . . . . . . . . . . . . . . . . . . . 22
+ 10. Security Considerations . . . . . . . . . . . . . . . . . . . 22
+ 11. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 22
+ 12. References . . . . . . . . . . . . . . . . . . . . . . . . . . 23
+ 12.1. Normative References . . . . . . . . . . . . . . . . . . . 23
+ 12.2. Informative References . . . . . . . . . . . . . . . . . . 24
+ Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 24
+ Intellectual Property and Copyright Statements . . . . . . . . . . 25
@@ -108,7 +108,6 @@
-
Barbato Expires December 18, 2006 [Page 2]
Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
@@ -120,13 +119,10 @@
maximum encoder flexibility, thus allowing it to scale competitively
over an exceptionally wide range of bitrates. At the high quality/
bitrate end of the scale (CD or DAT rate stereo, 16/24 bits), it is
- in the same league as MPEG-2 and MPC. Similarly, the version 1.1
- reference encoder can encode high-quality CD and DAT rate stereo at
- below 48k bits/sec without resampling to a lower rate. Vorbis is
- also intended for lower and higher sample rates (from 8kHz telephony
- to 192kHz digital masters) and a range of channel representations
- (monaural, polyphonic, stereo, quadraphonic, 5.1, ambisonic, or up to
- 255 discrete channels).
+ in the same league as AAC. Vorbis is also intended for lower and
+ higher sample rates (from 8kHz telephony to 192kHz digital masters)
+ and a range of channel representations (monaural, polyphonic, stereo,
+ quadraphonic, 5.1, ambisonic, or up to 255 discrete channels).
Vorbis encoded audio is generally encapsulated within an Ogg format
bitstream [1], which provides framing and synchronization. For the
@@ -148,7 +144,8 @@
its associated decoding codebooks as well as indicating if the
following packet contains fragmented Vorbis data and/or the number of
whole Vorbis data frames. The payload data contains the raw Vorbis
- bitstream information.
+ bitstream information. There are 3 types of Vorbis payload data, an
+ RTP packet MUST contain just one of them at time.
2.1. RTP Header
@@ -165,6 +162,8 @@
+
+
Barbato Expires December 18, 2006 [Page 3]
Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
@@ -183,7 +182,7 @@
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- Figure 1: RTP Header
+ Figure 1: RTP Header
The RTP header begins with an octet of fields (V, P, X, and CC) to
support specialized RTP uses (see [3] and [4] for details). For
@@ -210,7 +209,7 @@
Marker (M): 1 bit
Set to zero. Audio silence suppression not used. This conforms to
- section 4.1 of [15].
+ section 4.1 of [14].
Payload Type (PT): 7 bits
@@ -256,12 +255,12 @@
| Ident | F |VDT|# pkts.|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- Figure 2: Payload Header
+ Figure 2: Payload Header
Ident: 24 bits
This 24 bit field is used to associate the Vorbis data to a decoding
- Configuration.
+ Configuration. It is stored as network byte order integer.
Fragment type (F): 2 bits
@@ -282,8 +281,10 @@
Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
- This field sets the payload type for the Vorbis data in this RTP
- packet. There are currently three type of Vorbis payloads.
+ This field specifies the kind of Vorbis data stored in this RTP
+ packet. There are currently three different types of Vorbis
+ payloads. Each packet MUST contain only a single type of Vorbis
+ payload.
0 = Raw Vorbis payload
1 = Vorbis Packed Configuration payload
@@ -302,7 +303,7 @@
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 [14] typically produces
+ kilobytes). The reference implementation [13] 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
@@ -315,11 +316,12 @@
| length | vorbis packet data ..
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- Figure 3: Payload Data Header
+ Figure 3: Payload Data Header
Each Vorbis payload packet starts with a two octet length header,
- which is used to represent the size of the following data payload,
- followed by the raw Vorbis data padded to the nearest byte boundary.
+ 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. The length value is stored as network byte order integer.
For payloads which consist of multiple Vorbis packets the payload
data consists of the packet length followed by the packet data for
@@ -328,21 +330,20 @@
The Vorbis packet length header is the length of the Vorbis data
block only and does not count the length field.
- The payload packing of the Vorbis data packets MUST follow the
- guidelines set-out in [4] where the oldest packet occurs immediately
-
Barbato Expires December 18, 2006 [Page 6]
Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
+ The payload packing of the Vorbis data packets MUST follow the
+ guidelines set-out in [4] where the oldest packet occurs immediately
after the RTP packet header. Subsequent packets, if any, MUST follow
in temporal order.
Channel mapping of the audio is in accordance with the Vorbis I
- Specification [15].
+ Specification [14].
2.4. Example RTP Packet
@@ -363,7 +364,7 @@
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- Figure 4: Example Packet (RTP Headers)
+ Figure 4: Example Packet (RTP Headers)
Payload Data:
@@ -381,11 +382,9 @@
.. vorbis data |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- Figure 5: Example Packet (Payload Data)
+ Figure 5: Example Packet (Payload Data)
The payload data section of the RTP packet begins with the 24 bit
- Ident field followed by the one octet bitfield header, which has the
- number of Vorbis frames set to 2. Each of the Vorbis data frames is
@@ -394,6 +393,8 @@
Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
+ Ident field followed by the one octet bitfield header, which has the
+ number of Vorbis frames set to 2. Each of the Vorbis data frames is
prefixed by the two octets length field. The Packet Type and
Fragment Type are set to 0. The Configuration that will be used to
decode the packets is the one indexed by the ident value.
@@ -410,7 +411,7 @@
compressed data stream. These two 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 [15]
+ the compressed data. In addition, the Vorbis I specification [14]
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.
@@ -435,13 +436,11 @@
delivery methods that don't use RTP will not be described in this
document. For non chained streams, the Configuration recommended
delivery method is inline the Packed Configuration (Section 3.1.1) in
- the SDP as explained in the IANA considerations (Section 6.1)
+ the SDP as explained in the IANA considerations (Section 7.1)
section.
The 24 bit Ident field is used to map which Configuration will be
used to decode a packet. When the Ident field changes, it indicates
- that a change in the stream has taken place. The client application
- MUST have in advance the correct configuration and if the client
@@ -450,6 +449,8 @@
Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
+ that a change in the stream has taken place. The client application
+ MUST have in advance the correct configuration and if the client
detects a change in the Ident value and does not have this
information it MUST NOT decode the raw Vorbis data associated until
it fetches the correct Configuration.
@@ -457,17 +458,17 @@
3.1. In-band Header Transmission
The Packed Configuration (Section 3.1.1) Payload is sent in-band with
- the packet type bits set to match the payload type. Clients MUST be
- capable of dealing with fragmentation and periodic re-transmission of
- the configuration headers.
+ the packet type bits set to match the Vorbis Data Type. Clients MUST
+ be capable of dealing with fragmentation and periodic re-transmission
+ of the configuration headers.
3.1.1. Packed Configuration
- A Vorbis Packed Configuration is indicated with the payload type
+ 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 [15], the identification and the setup will be packed
+ specification [14], the identification and the setup will be packed
together, the comment header is completely suppressed. Is up to the
- client provide a minimal size comment header to the decoder if
+ client to provide a minimal size comment header to the decoder if
required by the implementation.
@@ -499,8 +500,6 @@
-
-
Barbato Expires December 18, 2006 [Page 9]
Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
@@ -536,7 +535,7 @@
.. Setup |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- Figure 6: Packed Configuration Figure
+ Figure 6: Packed Configuration Figure
The Ident field is set with the value that will be used by the Raw
Payload Packets to address this Configuration. The Fragment type is
@@ -551,17 +550,20 @@
SHOULD be used in out-of-band delivery and MUST be used when
Configuration is inlined in the SDP.
-3.2.1. Packed Headers
- As mentioned above the RECOMMENDED delivery vector for Vorbis
+
+
Barbato Expires December 18, 2006 [Page 10]
Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
+3.2.1. Packed Headers
+
+ As mentioned above the RECOMMENDED delivery vector for Vorbis
configuration data is via a retrieval method that can be performed
using a reliable transport protocol. As the RTP headers are not
required for this method of delivery the structure of the
@@ -580,7 +582,7 @@
| Packed header |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- Figure 7: Packed Headers Overview
+ Figure 7: Packed Headers Overview
Since the Configuration Ident and the Identification Header are fixed
length there is only a 2 byte length tag to define the length of the
@@ -600,15 +602,12 @@
.. Setup Header |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- Figure 8: Packed Headers Detail
+ Figure 8: Packed Headers Detail
The key difference between the in-band format and this one, is there
is no need for the payload header octet.
-3.2.1.1. Packed Headers IANA Considerations
- The following IANA considerations MUST only be applied to the packed
- headers.
@@ -618,10 +617,15 @@
Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
- MIME media type name: audio
+3.2.1.1. Packed Headers IANA Considerations
- MIME subtype: vorbis-config
+ The following IANA considerations MUST only be applied to the packed
+ headers.
+ MIME media type name: audio
+
+ MIME subtype: vorbis-config
+
Required Parameters:
None
@@ -660,20 +664,17 @@
Luca Barbato: <lu_zero at gentoo.org>
IETF Audio/Video Transport Working Group
- Intended usage: COMMON
-
-
-
-
Barbato Expires December 18, 2006 [Page 12]
Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
+ Intended usage: COMMON
+
Restriction on usage:
This media type doesn't depend on the transport.
@@ -693,18 +694,17 @@
successfully decode the stream.
Loss of Configuration Packet results in the halting of stream
- decoding and SHOULD be reported to the client as well as a loss
- report sent via RTCP.
+ decoding.
4. Comment Headers
- With the payload type flag set to 2, this indicates that the packet
- contain the comment metadata, such as artist name, track title 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 [15].
+ With the Vorbis Data Type flag set to 2, this indicates that the
+ packet contain the comment metadata, such as artist name, track title
+ 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 [14].
@@ -724,7 +724,6 @@
-
Barbato Expires December 18, 2006 [Page 13]
Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
@@ -752,7 +751,7 @@
.. Comment |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- Figure 9: Comment Packet
+ Figure 9: Comment Packet
The 2 bytes length field is necessary since this packet could be
fragmented.
@@ -816,7 +815,7 @@
.. vorbis data |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- Figure 10: Example Fragmented Packet (Packet 1)
+ Figure 10: Example Fragmented Packet (Packet 1)
In this packet the initial sequence number is 1000 and the timestamp
is xxxxx. The Fragment type is set to 1, the number of packets field
@@ -864,7 +863,7 @@
.. vorbis data |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- Figure 11: Example Fragmented Packet (Packet 2)
+ Figure 11: Example Fragmented Packet (Packet 2)
The Fragment type field is set to 2 and the number of packets field
is set to 0. For large Vorbis fragments there can be several of
@@ -920,7 +919,7 @@
.. vorbis data |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- Figure 12: Example Fragmented Packet (Packet 3)
+ Figure 12: Example Fragmented Packet (Packet 3)
This is the last Vorbis fragment packet. The Fragment type is set to
3 and the packet count remains set to 0. As in the previous packets
@@ -940,75 +939,83 @@
2 and MUST drop it. The next packet, which is the final fragmented
packet, MUST be dropped in the same manner. If the missing packet is
the last, the received two fragments will be kept and the incomplete
- vorbis packet decoded. Feedback reports on lost and dropped packets
- MUST be sent back via RTCP.
+ vorbis packet decoded.
- If a particular multicast session has a large number of participants
- care must be taken to prevent an RTCP feedback implosion, [10], in
- the event of packet loss from a large number of participants.
+ Loss of any of the Configuration fragment will result in the loss of
+ the full Configuration packet with the result detailed in the Loss of
+ Configuration Headers (Section 3.3) section.
+
Barbato Expires December 18, 2006 [Page 17]
Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
- Loss of any of the Configuration fragment will result in the loss of
- the full Configuration packet with the result detailed in the Loss of
- Configuration Headers (Section 3.3) section.
-
-
6. IANA Considerations
- MIME media type name: audio
+ MIME media type name: audio
- MIME subtype: vorbis
+ MIME subtype: vorbis
Required Parameters:
- delivery-method: indicates the delivery methods in use, the
+ rate: indicates the RTP timestamp clock rate as described in RTP
+ Profile for Audio and Video Conferences with Minimal Control.
+ [4]
+
+ channels: indicates the number of audio channels as described in
+ RTP Profile for Audio and Video Conferences with Minimal
+ Control. [4]
+
+ delivery-method: indicates the delivery methods in use, the
possible values are: inline, in_band, out_band/specific_name
Where "specific_name" is the name of the out of band delivery
method.
- configuration: the base16 [9] (hexadecimal) representation of the
+ configuration: the base16 [9] (hexadecimal) representation of the
Packed Headers (Section 3.2.1).
Optional Parameters:
- configuration-uri: the URI of the configuration headers in case of
- out of band transmission. In the form of
+ 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 the single ident packet could be retrived by their
- number, or aggregated in a single stream, aggregates MAY be
- compressed using bzip2 [13] or gzip [11] and an sha1 [12]
- checksum MAY be provided in the form of
- "protocol://path/to/resource/aggregated.bz2!sha1hash"
+ 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
+ [12] or gzip [10]. A sha1 [11] 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 hexadecimal representation of the
+ sha1hash of the above mentioned compressed aggregatedas in:
+ "protocol://path/to/resource/aggregated.bz2!sha1hash". The
+ trailing '/' discriminates which of two methods are in use.
Encoding considerations:
This media type is framed and contains binary data.
- Security Considerations:
- See Section 6 of RFC XXXX.
- Interoperability considerations:
- None
+Barbato Expires December 18, 2006 [Page 18]
+
+Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
+ Security Considerations:
+ See Section 6 of RFC XXXX.
-Barbato Expires December 18, 2006 [Page 18]
-
-Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
+ Interoperability considerations:
+ None
Published specification:
@@ -1028,8 +1035,8 @@
Person & email address to contact for further information:
- Luca Barbato: <lu_zero at gentoo.org>
- IETF Audio/Video Transport Working Group
+ Luca Barbato: <lu_zero at gentoo.org> IETF Audio/Video Transport
+ Working Group
Intended usage:
@@ -1049,23 +1056,28 @@
IETF AVT Working Group
-6.1. Mapping MIME Parameters into SDP
- The information carried in the MIME media type specification has a
- specific mapping to fields in the Session Description Protocol (SDP)
- [5], which is commonly used to describe RTP sessions. When SDP is
- used to specify sessions the mapping are as follows:
-
-
-
Barbato Expires December 18, 2006 [Page 19]
Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
+7. SDP related considerations
+
+ The following paragraphs defines the mapping of the parameters
+ described in the IANA considerations section and their usage in the
+ Offer/Answer Model [8].
+
+7.1. Mapping MIME Parameters into SDP
+
+ The information carried in the MIME media type specification has a
+ specific mapping to fields in the Session Description Protocol (SDP)
+ [5], which is commonly used to describe RTP sessions. When SDP is
+ used to specify sessions the mapping are as follows:
+
o The MIME type ("audio") goes in SDP "m=" as the media name.
o The MIME subtype ("vorbis") goes in SDP "a=rtpmap" as the encoding
@@ -1095,12 +1107,20 @@
specified in the rtpmap attribute MUST match the Vorbis sample rate
value. An example is found below.
-6.1.1. SDP Example
+7.1.1. SDP Example
The following example shows a basic SDP single stream. The first
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.
+
+
+
+Barbato Expires December 18, 2006 [Page 20]
+
+Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
+
+
The inline base16 [9] configuration string is omitted because of the
lenght.
c=IN IP4 192.0.0.1
@@ -1110,25 +1130,18 @@
delivery-method=out_band/rtsp;
configuration-uri=rtsp://path/to/the/resource; delivery-
method=out_band/http; configuration-uri=http://another/path/to/
- resource/aggregate.bz2!sha1hash;
+ resource/aggregate.bz2!8b6237eb5154a0ea12811a94e8e2697b3312bc6c;
Note that the payload format (encoding) names are commonly shown in
upper case. MIME subtypes are commonly shown in lower case. These
-
-
-
-Barbato Expires December 18, 2006 [Page 20]
-
-Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
-
-
names are case-insensitive in both places. Similarly, parameter
names are case-insensitive both in MIME types and in the default
mapping to the SDP a=fmtp attribute. The exception regarding case
sensitivity is the configuration-uri URI which MUST be regarded as
- being case sensitive.
+ being case sensitive. The a=fmtp line is a single line even if it is
+ presented broken because of clarity.
-6.2. Usage with the SDP Offer/Answer Model
+7.2. Usage with the SDP Offer/Answer Model
The offer, as described in An Offer/Answer Model Session Description
Protocol [8], may contain a large number of delivery methods per
@@ -1137,7 +1150,7 @@
altered on answer otherwise.
-7. Congestion Control
+8. Congestion Control
Vorbis clients SHOULD send regular receiver reports detailing
congestion. A mechanism for dynamically downgrading the stream,
@@ -1146,19 +1159,26 @@
alternative would be to redirect the client to a lower bitrate stream
if one is available.
- If a particular multicast session has a large number of participants
- care must be taken to prevent an RTCP feedback implosion, [10], in
- the event of congestion.
+9. Examples
-8. Examples
-
The following examples are common usage patterns that MAY be applied
in such situations, the main scope of this section is to explain
better usage of the transmission vectors.
-8.1. Stream Radio
+
+
+
+
+
+Barbato Expires December 18, 2006 [Page 21]
+
+Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
+
+
+9.1. Stream Radio
+
This is one of the most common situation: one single server streaming
content in multicast, the clients may start a session at random time.
The content itself could be a mix of live stream, as the wj's voice,
@@ -1170,24 +1190,16 @@
On join the client will receive the current Configuration necessary
to decode the current stream inlined in the SDP so that the decoding
-
-
-
-Barbato Expires December 18, 2006 [Page 21]
-
-Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
-
-
will start immediately after.
When the streamed content changes the new Configuration is sent in-
band before the actual stream, and the Configuration that has to be
- sent inline in the SDP updated. Since the inline method is
+ sent inline in the SDP updated. Since the in-band method is
unreliable, an out of band fallback is provided.
The client could choose to fetch the Configuration from the alternate
- source as soon it discovers a Configuration packet got lost inline or
- use selective retransmission [17], if the server supports the
+ source as soon it discovers a Configuration packet got lost in-band
+ or use selective retransmission [15], if the server supports the
feature.
A serverside optimization would be to keep an hash list of the
@@ -1199,7 +1211,7 @@
already known.
-9. Security Considerations
+10. Security Considerations
RTP packets using this payload format are subject to the security
considerations discussed in the RTP specification [3]. This implies
@@ -1210,9 +1222,17 @@
taken to prevent buffer overflows in the client applications.
-10. Acknowledgments
+11. Acknowledgments
This document is a continuation of draft-moffitt-vorbis-rtp-00.txt
+
+
+
+Barbato Expires December 18, 2006 [Page 22]
+
+Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
+
+
and draft-kerr-avt-vorbis-rtp-04.txt. The MIME type section is a
continuation of draft-short-avt-rtp-vorbis-mime-00.txt.
@@ -1226,18 +1246,10 @@
Ridolfo, Francesco Varano, Giampaolo Mancini, Juan Carlos De Martin.
+12. References
+12.1. Normative References
-
-Barbato Expires December 18, 2006 [Page 22]
-
-Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
-
-
-11. References
-
-11.1. Normative References
-
[1] Pfeiffer, S., "The Ogg Encapsulation Format Version 0",
RFC 3533.
@@ -1265,87 +1277,34 @@
[9] Josefsson, S., "The Base16, Base32, and Base64 Data Encodings",
RFC 3548.
- [10] Ott, J., Wenger, S., Sato, N., Burmeister, C., and J. Rey,
- "Extended RTP Profile for RTCP-based Feedback (RTP/AVPF)",
- Internet Draft (draft-ietf-avt-rtcp-feedback-11: Work in
- progress).
-
- [11] Deutsch, P., "GZIP file format specification version 4.3",
+ [10] Deutsch, P., "GZIP file format specification version 4.3",
RFC 1952.
- [12] National Institute of Standards and Technology, "Secure Hash
- Standard", May 1993.
+ [11] National Institute of Standards and Technology, "Secure Hash
- [13] Seward, J., "libbz2 and bzip2".
-11.2. Informative References
- [14] "libvorbis: Available from the Xiph website,
- http://www.xiph.org".
-
-
-
Barbato Expires December 18, 2006 [Page 23]
Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
- [15] "Ogg Vorbis I specification: Codec setup and packet decode.
- Available from the Xiph website, http://www.xiph.org".
+ Standard", May 1993.
- [16] "Ogg Vorbis I specification: Comment field and header
- specification. Available from the Xiph website,
- http://www.xiph.org".
+ [12] Seward, J., "libbz2 and bzip2".
- [17] Friedman, T., Caceres, R., and A. Clark, "RTP Control Protocol
- Extended Reports (RTCP XR)", RFC 3611, November 2003.
+12.2. Informative References
+ [13] "libvorbis: Available from the Xiph website,
+ http://www.xiph.org".
+ [14] "Ogg Vorbis I specification: Codec setup and packet decode.
+ Available from the Xiph website, http://www.xiph.org".
+ [15] Friedman, T., Caceres, R., and A. Clark, "RTP Control Protocol
+ Extended Reports (RTCP XR)", RFC 3611, November 2003.
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-Barbato Expires December 18, 2006 [Page 24]
-
-Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
-
-
Author's Address
Luca Barbato
@@ -1381,29 +1340,30 @@
+Barbato Expires December 18, 2006 [Page 24]
+
+Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
+Full Copyright Statement
+ Copyright (C) The IETF Trust (2006).
+ This document is subject to the rights, licenses and restrictions
+ contained in BCP 78, and except as set forth therein, the authors
+ retain all their rights.
+ This document and the information contained herein are provided on an
+ "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
+ OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND
+ THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS
+ OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF
+ THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
+ WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
+Intellectual Property
-
-
-
-
-
-
-
-
-Barbato Expires December 18, 2006 [Page 25]
-
-Internet-Draft draft-ietf-avt-rtp-vorbis-01 June 2006
-
-
-Intellectual Property Statement
-
The IETF takes no position regarding the validity or scope of any
Intellectual Property Rights or other rights that might be claimed to
pertain to the implementation or use of the technology described in
@@ -1427,32 +1387,15 @@
ietf-ipr at ietf.org.
-Disclaimer of Validity
-
- This document and the information contained herein are provided on an
- "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
- OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
- ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
- INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
- INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
- WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
-
-
-Copyright Statement
-
- Copyright (C) The Internet Society (2006). This document is subject
- to the rights, licenses and restrictions contained in BCP 78, and
- except as set forth therein, the authors retain all their rights.
-
-
Acknowledgment
- Funding for the RFC Editor function is currently provided by the
- Internet Society.
+ Funding for the RFC Editor function is provided by the IETF
+ Administrative Support Activity (IASA).
-Barbato Expires December 18, 2006 [Page 26]
+
+Barbato Expires December 18, 2006 [Page 25]
Modified: trunk/vorbis/doc/draft-ietf-avt-rtp-vorbis-01.xml
===================================================================
--- trunk/vorbis/doc/draft-ietf-avt-rtp-vorbis-01.xml 2007-01-20 14:34:29 UTC (rev 12363)
+++ trunk/vorbis/doc/draft-ietf-avt-rtp-vorbis-01.xml 2007-01-20 18:39:33 UTC (rev 12364)
@@ -238,7 +238,7 @@
Vorbis Data Type (VDT): 2 bits</t>
<t>
This field specifies the kind of Vorbis data stored in this RTP packet. There
-are currently three different types of Vorbis payloads.
+are currently three different types of Vorbis payloads. Each packet MUST contain only a single type of Vorbis payload.
</t>
<vspace blankLines="1" />
@@ -1013,7 +1013,13 @@
<vspace blankLines="1" />
</list>
+</section>
+<section anchor="SDP related considerations" title="SDP related considerations">
+<t>
+The following paragraphs defines the mapping of the parameters described in the IANA considerations section and their usage in the <xref target="rfc3264">Offer/Answer Model</xref>.
+</t>
+
<section anchor="Mapping MIME Parameters into SDP" title="Mapping MIME Parameters into SDP">
<t>
@@ -1321,13 +1327,7 @@
<title>Ogg Vorbis I specification: Codec setup and packet decode. Available from the Xiph website, http://www.xiph.org</title>
</front>
</reference>
-
-<reference anchor="v-comment">
-<front>
-<title>Ogg Vorbis I specification: Comment field and header specification. Available from the Xiph website,
-http://www.xiph.org</title>
-</front>
-</reference>
+
<reference anchor="RFC3611">
<front>
<title>RTP Control Protocol Extended Reports (RTCP XR)</title>
More information about the commits
mailing list