RTP Payload Format for ISO/IEC 21122 (JPEG XS)
draft-ietf-payload-rtp-jpegxs-16
| Document | Type | Active Internet-Draft (avtcore WG) | |
|---|---|---|---|
| Authors | Sébastien Lugan , Antonin Descampe , Corentin Damman , Thomas Richter , Tim Bruylants | ||
| Last updated | 2021-06-09 | ||
| Replaces | draft-lugan-payload-rtp-jpegxs | ||
| Stream | Internet Engineering Task Force (IETF) | ||
| Intended RFC status | Proposed Standard | ||
| Formats | plain text xml pdf htmlized bibtex | ||
| Reviews | |||
| Stream | WG state | Submitted to IESG for Publication (wg milestone: Mar 2020 - Submit RTP Payload F... ) | |
| Document shepherd | Bernard Aboba | ||
| Shepherd write-up | Show (last changed 2021-05-03) | ||
| IESG | IESG state | IESG Evaluation | |
| Action Holders | |||
| Consensus Boilerplate | Yes | ||
| Telechat date |
On agenda of 2021-06-17 IESG telechat
Needs 3 more YES or NO OBJECTION positions to pass. |
||
| Responsible AD | Murray Kucherawy | ||
| Send notices to | Ali Begen <ali.begen@networked.media>, bernard.aboba@gmail.com | ||
| IANA | IANA review state | Version Changed - Review Needed | |
avtcore S. Lugan
Internet-Draft intoPIX
Intended status: Standards Track A. Descampe
Expires: December 11, 2021 UCL
C. Damman
intoPIX
T. Richter
IIS
T. Bruylants
intoPIX
June 9, 2021
RTP Payload Format for ISO/IEC 21122 (JPEG XS)
draft-ietf-payload-rtp-jpegxs-16
Abstract
This document specifies a Real-Time Transport Protocol (RTP) payload
format to be used for transporting JPEG XS (ISO/IEC 21122) encoded
video. JPEG XS is a low-latency, lightweight image coding system.
Compared to an uncompressed video use case, it allows higher
resolutions and frame rates, while offering visually lossless
quality, reduced power consumption, and end-to-end latency confined
to a fraction of a frame.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on December 11, 2021.
Copyright Notice
Copyright (c) 2021 IETF Trust and the persons identified as the
document authors. All rights reserved.
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This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions, Definitions, and Abbreviations . . . . . . . . . 3
3. Media Format Description . . . . . . . . . . . . . . . . . . 4
3.1. Image Data Structures . . . . . . . . . . . . . . . . . . 5
3.2. Codestream . . . . . . . . . . . . . . . . . . . . . . . 5
3.3. Video support box and colour specification box . . . . . 5
3.4. JPEG XS Frame . . . . . . . . . . . . . . . . . . . . . . 6
4. RTP Payload Format . . . . . . . . . . . . . . . . . . . . . 6
4.1. RTP packetization . . . . . . . . . . . . . . . . . . . . 7
4.2. RTP Header Usage . . . . . . . . . . . . . . . . . . . . 9
4.3. Payload Header Usage . . . . . . . . . . . . . . . . . . 11
4.4. Payload Data . . . . . . . . . . . . . . . . . . . . . . 13
5. Traffic Shaping and Delivery Timing . . . . . . . . . . . . . 18
6. Congestion Control Considerations . . . . . . . . . . . . . . 19
7. Payload Format Parameters . . . . . . . . . . . . . . . . . . 19
7.1. Media Type Registration . . . . . . . . . . . . . . . . . 19
8. SPD Parameters . . . . . . . . . . . . . . . . . . . . . . . 24
8.1. Mapping of Payload Type Parameters to SDP . . . . . . . . 24
8.2. Usage with SDP Offer/Answer Model . . . . . . . . . . . . 25
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 26
10. Security Considerations . . . . . . . . . . . . . . . . . . . 26
11. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 27
12. RFC Editor Considerations . . . . . . . . . . . . . . . . . . 27
13. References . . . . . . . . . . . . . . . . . . . . . . . . . 27
13.1. Normative References . . . . . . . . . . . . . . . . . . 27
13.2. Informative References . . . . . . . . . . . . . . . . . 29
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 30
1. Introduction
This document specifies a payload format for packetization of JPEG XS
[ISO21122-1] encoded video signals into the Real-time Transport
Protocol (RTP) [RFC3550].
The JPEG XS coding system offers compression and recompression of
image sequences with very moderate computational resources while
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remaining robust under multiple compression and decompression cycles
and mixing of content sources, e.g. embedding of subtitles, overlays
or logos. Typical target compression ratios ensuring visually
lossless quality are in the range of 2:1 to 10:1, depending on the
nature of the source material. The end-to-end latency can be
confined to a fraction of a frame, typically between a small number
of lines down to below a single line.
2. Conventions, Definitions, and Abbreviations
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
Application Data Unit (ADU)
The unit of source data provided as payload to the transport
layer, and corresponding, in this RTP payload definition, to a
single JPEG XS frame.
Colour specification box (CS box)
A ISO colour specification box defined in JPEG XS Part 3
[ISO21122-3] that includes colour-related metadata required to
correctly display JPEG XS frames, such as colour primaries,
transfer characteristics and matrix coefficients.
EOC marker
A marker that consists of the two bytes 0xff11 indicating the end
of a JPEG XS codestream.
JPEG XS codestream
A sequence of bytes representing a compressed image formatted
according to JPEG XS Part 1 [ISO21122-1].
JPEG XS codestream header
A sequence of bytes, starting with a SOC marker, at the beginning
of each JPEG XS codestream encoded in multiple markers and marker
segments that does not carry entropy coded data, but metadata such
as the frame dimension and component precision.
JPEG XS frame
A JPEG XS picture segment in the case of a progressive frame, or,
in the case of an interlaced frame, the concatenation of two JPEG
XS picture segments.
JPEG XS header segment
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The concatenation of a video support box [ISO21122-3], a colour
specification box [ISO21122-3], and a JPEG XS codestream header.
JPEG XS picture segment
The concatenation of a video support box [ISO21122-3], a colour
specification box [ISO21122-3], and a JPEG XS codestream.
JPEG XS stream
A sequence of JPEG XS frames.
Marker
A two-byte functional sequence that is part of a JPEG XS
codestream starting with a 0xff byte and a subsequent byte
defining its function.
Marker segment
A marker along with a 16-bit marker size and payload data
following the size.
Packetization unit
A portion of an Application Data Unit whose boundaries coincide
with boundaries of RTP packet payloads (excluding payload header),
i.e. the first (resp. last) byte of a packetization unit is the
first (resp. last) byte of a RTP packet payload (excluding its
payload header).
Slice
The smallest independently decodable unit of a JPEG XS codestream,
bearing in mind that it decodes to wavelet coefficients which
still require inverse wavelet filtering to give an image.
SOC marker
A marker that consists of the two bytes 0xff10 indicating the
start of a JPEG XS codestream. The SOC marker is considered an
integral part of the JPEG XS codestream header.
Video support box (VS box)
An ISO video support box, as defined in [ISO21122-3], that
includes metadata required to play back a JPEG XS stream, such as
its maximum bitrate, its subsampling structure, its buffer model
and its frame rate.
3. Media Format Description
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3.1. Image Data Structures
JPEG XS is a low-latency lightweight image coding system for coding
continuous-tone grayscale or continuous-tone colour digital images.
This coding system provides an efficient representation of image
signals through the mathematical tool of wavelet analysis. The
wavelet filter process separates each component into multiple bands,
where each band consists of multiple coefficients describing the
image signal of a given component within a frequency domain specific
to the wavelet filter type, i.e. the particular filter corresponding
to the band.
Wavelet coefficients are grouped into precincts, where each precinct
includes all coefficients over all bands that contribute to a spatial
region of the image.
One or multiple precincts are furthermore combined into slices
consisting of an integer number of precincts. Precincts do not cross
slice boundaries, and wavelet coefficients in precincts that are part
of different slices can be decoded independently from each other.
Note, however, that the wavelet transformation runs across slice
boundaries. A slice always extends over the full width of the image,
but may only cover parts of its height.
3.2. Codestream
A JPEG XS codestream header, starting with an SOC marker, followed by
one or more slices, and terminated by an EOC marker form a JPEG XS
codestream.
The JPEG XS codestream format, including the definition of all
markers, is further defined in [ISO21122-1]. It represents sample
values of a single image, without any interpretation relative to a
colour space.
3.3. Video support box and colour specification box
While the information defined in the codestream is sufficient to
reconstruct the sample values of one image, the interpretation of the
samples remains undefined by the codestream itself. This
interpretation is given by the video support box and the colour
specification box which contain significant information to correctly
play the JPEG XS stream. The layout and syntax of these boxes,
together with their content, are defined in [ISO21122-3].
The video support box provides information on the maximum bitrate,
the frame rate, the interlaced mode (progressive or interlaced), the
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subsampling image format, the informative timecode of the current
JPEG XS frame, the profile, level/sublevel used, and optionally on
the buffer model and the mastering display metadata.
Note that the profile and level/sublevel, specified by respectively
the Ppih and Plev fields, specify limits on the capabilities needed
to decode the codestream and handle the output. Profiles represent a
limit on the required algorithmic features and parameter ranges used
in the codestream. The combination of level and sublevel defines a
lower bound on the required throughput for a decoder in respectively
the image (or decoded) domain and the codestream (or coded) domain.
The actual defined profiles and level/sublevels, along with the
associated values for the Ppih and Plev fields, are defined in
[ISO21122-2].
The colour specification box indicates the colour primaries, transfer
characteristics, matrix coefficients and video full range flag needed
to specify the colour space of the video stream.
3.4. JPEG XS Frame
The concatenation of a video support box, a colour specification box,
and a JPEG XS codestream forms a JPEG XS picture segment.
In the case of a progressive video stream, each JPEG XS frame
consists of one single JPEG XS picture segment.
In the case of an interlaced video stream, each JPEG XS frame is made
of two concatenated JPEG XS picture segments. The codestream of each
picture segment corresponds exclusively to one of the two fields of
the interlaced frame. Both picture segments SHALL contain identical
boxes (i.e. concatenation of the video support box and the colour
specification box is byte exact the same for both picture segments of
the frame).
Note that the interlaced mode, as signaled by the frat field
[ISO21122-3] in the video support box, indicates either progressive,
interlaced top-field first, or interlaced bottom-field first mode.
Thus, in the case of interlaced content, its value SHALL also be
identical in both picture segments.
4. RTP Payload Format
This section specifies the payload format for JPEG XS streams over
the Real-time Transport Protocol (RTP) [RFC3550].
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In order to be transported over RTP, each JPEG XS stream is
transported in a distinct RTP stream, identified by a distinct
Synchronization source (SSRC) [RFC3550].
A JPEG XS stream is divided into Application Data Units (ADUs), each
ADU corresponding to a single JPEG XS frame.
4.1. RTP packetization
An ADU is made of several packetization units. If a packetization
unit is bigger than the maximum size of a RTP packet payload, the
unit is split into multiple RTP packet payloads, as illustrated in
Figure 1. As seen there, each packet SHALL contain (part of) one and
only one packetization unit. A packetization unit may extend over
multiple packets. The payload of every packet SHALL have the same
size (based e.g. on the Maximum Transfer Unit of the network), except
(possibly) the last packet of a packetization unit. The boundaries
of a packetization unit SHALL coincide with the boundaries of the
payload of a packet (excluding the payload header), i.e. the first
(resp. last) byte of the packetization unit SHALL be the first (resp.
last) byte of the payload (excluding its header).
RTP +-----+------------------------+
Packet #1 | Hdr | Packetization unit #1 |
+-----+------------------------+
RTP +-----+--------------------------------------+
Packet #2 | Hdr | Packetization unit #2 |
+-----+--------------------------------------+
RTP +-----+--------------------------------------------------+
Packet #3 | Hdr | Packetization unit #3 (part 1/3) |
+-----+--------------------------------------------------+
RTP +-----+--------------------------------------------------+
Packet #4 | Hdr | Packetization unit #3 (part 2/3) |
+-----+--------------------------------------------------+
RTP +-----+----------------------------------------------+
Packet #5 | Hdr | Packetization unit #3 (part 3/3) |
+-----+----------------------------------------------+
...
RTP +-----+-----------------------------------------+
Packet #P | Hdr | Packetization unit #N (part q/q) |
+-----+-----------------------------------------+
Figure 1: Example of ADU packetization
There are two different packetization modes defined for this RTP
payload format.
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1. Codestream packetization mode: in this mode, the packetization
unit SHALL be the entire JPEG XS picture segment (i.e. codestream
preceded by boxes). This means that a progressive frame will
have a single packetization unit, while an interlaced frame will
have two. The progressive case is illustrated in Figure 2.
2. Slice packetization mode: in this mode, the packetization unit
SHALL be the slice, i.e. there SHALL be data from no more than
one slice per RTP packet. The first packetization unit SHALL be
made of the JPEG XS header segment (i.e. the concatenation of the
VS box, the CS box and the JPEG XS codestream header). This
first unit is then followed by successive units, each containing
one and only one slice. The packetization unit containing the
last slice of a JPEG XS codestream SHALL also contain the EOC
marker immediately following this last slice. This is
illustrated in Figure 3. In the case of an interlaced frame, the
JPEG XS header segment of the second field SHALL be in its own
packetization unit.
RTP +-----+--------------------------------------------------+
Packet #1 | Hdr | VS box + CS box + JPEG XS codestream (part 1/q) |
+-----+--------------------------------------------------+
RTP +-----+--------------------------------------------------+
Packet #2 | Hdr | JPEG XS codestream (part 2/q) |
+-----+--------------------------------------------------+
...
RTP +-----+--------------------------------------+
Packet #P | Hdr | JPEG XS codestream (part q/q) |
+-----+--------------------------------------+
Figure 2: Example of codestream packetization mode
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RTP +-----+----------------------------+
Packet #1 | Hdr | JPEG XS header segment |
+-----+----------------------------+
RTP +-----+--------------------------------------------------+
Packet #2 | Hdr | Slice #1 (part 1/2) |
+-----+--------------------------------------------------+
RTP +-----+-------------------------------------------+
Packet #3 | Hdr | Slice #1 (part 2/2) |
+-----+-------------------------------------------+
RTP +-----+--------------------------------------------------+
Packet #4 | Hdr | Slice #2 (part 1/3) |
+-----+--------------------------------------------------+
...
RTP +-----+---------------------------------------+
Packet #P | Hdr | Slice #N (part q/q) + EOC marker |
+-----+---------------------------------------+
Figure 3: Example of slice packetization mode
Due to the constant bit-rate of JPEG XS, the codestream packetization
mode guarantees that a JPEG XS RTP stream will produce a constant
number of bytes per frame, and a constant number of RTP packets per
frame. To reach the same guarantee with the slice packetization
mode, an additional mechanism is required. This can involve a
constraint at the rate allocation stage in the JPEG XS encoder to
impose a constant bit-rate at the slice level, the usage of padding
data, or the insertion of empty RTP packets (i.e. a RTP packet whose
payload data is empty).
4.2. RTP Header Usage
The format of the RTP header is specified in [RFC3550] and reprinted
in Figure 4 for convenience. This RTP payload format uses the fields
of the header in a manner consistent with that specification.
The RTP payload (and the settings for some RTP header bits) for
packetization units are specified in Section 4.3.
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| V |P|X| CC |M| PT | sequence number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| timestamp |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| synchronization source (SSRC) identifier |
+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
| contributing source (CSRC) identifiers |
| .... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: RTP header according to RFC 3550
The version (V), padding (P), extension (X), CSRC count (CC),
sequence number, synchronization source (SSRC) and contributing
source (CSRC) fields follow their respective definitions in
[RFC3550].
The remaining RTP header information to be set according to this RTP
payload format is set as follows:
Marker (M) [1 bit]:
If progressive scan video is being transmitted, the marker bit
denotes the end of a video frame. If interlaced video is being
transmitted, it denotes the end of the field. The marker bit
SHALL be set to 1 for the last packet of the video frame/field.
It SHALL be set to 0 for all other packets.
Payload Type (PT) [7 bits]:
A dynamically allocated payload type field that designates the
payload as JPEG XS video.
Timestamp [32 bits]:
The RTP timestamp is set to the sampling timestamp of the content.
A 90 kHz clock rate SHALL be used.
As specified in [RFC3550] and [RFC4175], the RTP timestamp
designates the sampling instant of the first octet of the frame to
which the RTP packet belongs. Packets SHALL NOT include data from
multiple frames, and all packets belonging to the same frame SHALL
have the same timestamp. Several successive RTP packets will
consequently have equal timestamps if they belong to the same
frame (that is until the marker bit is set to 1, marking the last
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packet of the frame), and the timestamp is only increased when a
new frame begins.
If the sampling instant does not correspond to an integer value of
the clock, the value SHALL be truncated to the next lowest
integer, with no ambiguity.
4.3. Payload Header Usage
The first four bytes of the payload of an RTP packet in this RTP
payload format are referred to as the payload header. Figure 5
illustrates the structure of this payload header.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|T|K|L| I |F counter| SEP counter | P counter |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: Payload header
The payload header consists of the following fields:
Transmission mode (T) [1 bit]:
The T bit is set to indicate that packets are sent sequentially by
the transmitter. This information allows a receiver to dimension
its input buffer(s) accordingly. If T=0, nothing can be assumed
about the transmission order and packets may be sent out-of-order
by the transmitter. If T=1, packets SHALL be sent sequentially by
the transmitter.
pacKetization mode (K) [1 bit]:
The K bit is set to indicate which packetization mode is used.
K=0 indicates codestream packetization mode, while K=1 indicates
slice packetization mode. In the case that the Transmission mode
(T) is set to 0, the slice packetization mode SHALL be used and K
SHALL be set to 1.
Last (L) [1 bit]:
The L bit is set to indicate the last packet of a packetization
unit. As the end of the frame also ends the packet containing the
last unit of the frame, the L bit is set whenever the M bit is
set. If codestream packetization mode is used, L bit and M bit
are equivalent.
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Interlaced information (I) [2 bit]:
These 2 bits are used to indicate how the JPEG XS frame is scanned
(progressive or interlaced). In case of an interlaced frame, they
also indicate which JPEG XS picture segment the payload is part of
(first or second).
00: The payload is progressively scanned.
01: Reserved for future use.
10: The payload is part of the first JPEG XS picture segment of
an interlaced video frame. The height specified in the
included JPEG XS codestream header is half of the height of the
entire displayed image.
11: The payload is part of the second JPEG XS picture segment of
an interlaced video frame. The height specified in the
included JPEG XS codestream header is half of the height of the
entire displayed image.
F counter [5 bits]:
The frame (F) counter identifies the frame number modulo 32 to
which a packet belongs. Frame numbers are incremented by 1 for
each frame transmitted. The frame number, in addition to the
timestamp, may help the decoder manage its input buffer and bring
packets back into their natural order.
SEP counter [11 bits]:
The Slice and Extended Packet (SEP) counter is used differently
depending on the packetization mode.
* In the case of codestream packetization mode (K=0), this
counter resets whenever the Packet counter resets (see
hereunder), and increments by 1 whenever the Packet counter
overruns.
* In the case of slice packetization mode (K=1), this counter
identifies the slice modulo 2047 to which the packet
contributes. If the data belongs to the JPEG XS header
segment, this field SHALL have its maximal value, namely 2047 =
0x07ff. Otherwise, it is the slice index modulo 2047. Slice
indices are counted from 0 (corresponding to the top of the
frame).
P counter [11 bits]:
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The packet (P) counter identifies the packet number modulo 2048
within the current packetization unit. It is set to 0 at the
start of the packetization unit and incremented by 1 for every
subsequent packet (if any) belonging to the same unit.
Practically, if codestream packetization mode is enabled, this
field counts the packets within a JPEG XS picture segment and is
extended by the SEP counter when it overruns. If slice
packetization mode is enabled, this field counts the packets
within a slice or within the JPEG XS header segment.
4.4. Payload Data
The payload data of a JPEG XS RTP stream consists of a concatenation
of multiple JPEG XS frames. Within the RTP stream, all of the video
support boxes and all of the colour specification boxes SHALL retain
their respective layouts for each JPEG XS frame. Thus, each video
support box in the RTP stream SHALL define the same sub boxes. The
effective values in the boxes are allowed to change under the
condition that their relative byte offsets SHALL NOT change.
Each JPEG XS frame is the concatenation of one or more packetization
unit(s), as explained in Section 4.1. Figure 6 depicts this layout
for a progressive frame in the codestream packetization mode,
Figure 7 depicts this layout for an interlaced frame in the
codestream packetization mode, Figure 8 depicts this layout for a
progressive frame in the slice packetization mode and Figure 9
depicts this layout for an interlaced frame in the slice
packetization mode. The Frame counter value is not indicated because
the value is constant for all packetization units of a given frame.
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+=====[ Packetization unit (PU) #1 ]====+
| Video support box | SEP counter=0
| +---------------------------------+ | P counter=0
| : Sub boxes of the VS box : |
| +---------------------------------+ |
+- - - - - - - - - - - - - - - - - - - -+
| Colour specification box |
| +---------------------------------+ |
| : Fields of the CS box : |
| +---------------------------------+ |
+- - - - - - - - - - - - - - - - - - - -+
| JPEG XS codestream |
: (part 1/q) : M=0, K=0, L=0, I=00
+---------------------------------------+
| JPEG XS codestream | SEP counter=0
| (part 2/q) | P counter=1
: : M=0, K=0, L=0, I=00
+---------------------------------------+
| JPEG XS codestream | SEP counter=0
| (part 3/q) | P counter=2
: : M=0, K=0, L=0, I=00
+---------------------------------------+
: :
+---------------------------------------+
| JPEG XS codestream | SEP counter=1
| (part 2049/q) | P counter=0
: : M=0, K=0, L=0, I=00
+---------------------------------------+
: :
+---------------------------------------+
| JPEG XS codestream | SEP counter=(q-1) div 2048
| (part q/q) | P counter=(q-1) mod 2048
: : M=1, K=0, L=1, I=00
+=======================================+
Figure 6: Example of JPEG XS Payload Data (codestream packetization
mode, progressive frame)
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+=====[ Packetization unit (PU) #1 ]====+
| Video support box | SEP counter=0
+- - - - - - - - - - - - - - - - - - - -+ P counter=0
| Colour specification box |
+- - - - - - - - - - - - - - - - - - - -+
| JPEG XS codestream (1st field) |
: (part 1/q) : M=0, K=0, L=0, I=10
+---------------------------------------+
| JPEG XS codestream (1st field) | SEP counter=0
| (part 2/q) | P counter=1
: : M=0, K=0, L=0, I=10
+---------------------------------------+
: :
+---------------------------------------+
| JPEG XS codestream (1st field) | SEP counter=1
| (part 2049/q) | P counter=0
: : M=0, K=0, L=0, I=10
+---------------------------------------+
: :
+---------------------------------------+
| JPEG XS codestream (1st field) | SEP counter=(q-1) div 2048
| (part q/q) | P counter=(q-1) mod 2048
: : M=1, K=0, L=1, I=10
+===============[ PU #2 ]===============+
| Video support box | SEP counter=0
+- - - - - - - - - - - - - - - - - - - -+ P counter=0
| Colour specification box |
+- - - - - - - - - - - - - - - - - - - -+
| JPEG XS codestream (2nd field) |
| (part 1/q) |
: : M=0, K=0, L=0, I=11
+---------------------------------------+
| JPEG XS codestream (2nd field) | SEP counter=0
| (part 2/q) | P counter=1
: : M=0, K=0, L=0, I=11
+---------------------------------------+
: :
+---------------------------------------+
| JPEG XS codestream (2nd field) | SEP counter=(q-1) div 2048
| (part q/q) | P counter=(q-1) mod 2048
: : M=1, K=0, L=1, I=11
+=======================================+
Figure 7: Example of JPEG XS Payload Data (codestream packetization
mode, interlaced frame)
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+===[ PU #1: JPEG XS Header segment ]===+
| Video support box | SEP counter=0x07FF
+- - - - - - - - - - - - - - - - - - - -+ P counter=0
| Colour specification box |
+- - - - - - - - - - - - - - - - - - - -+
| JPEG XS codestream header |
| +---------------------------------+ |
| : Markers and marker segments : |
| +---------------------------------+ | M=0, T=0, K=1, L=1, I=00
+==========[ PU #2: Slice #1 ]==========+
| +---------------------------------+ | SEP counter=0
| | SLH Marker | | P counter=0
| +---------------------------------+ |
| : Entropy Coded Data : |
| +---------------------------------+ | M=0, T=0, K=1, L=1, I=00
+==========[ PU #3: Slice #2 ]==========+
| Slice #2 | SEP counter=1
| (part 1/q) | P counter=0
: : M=0, T=0, K=1, L=0, I=00
+---------------------------------------+
| Slice #2 | SEP counter=1
| (part 2/q) | P counter=1
: : M=0, T=0, K=1, L=0, I=00
+---------------------------------------+
: :
+---------------------------------------+
| Slice #2 | SEP counter=1
| (part q/q) | P counter=q-1
: : M=0, T=0, K=1, L=1, I=00
+=======================================+
: :
+========[ PU #N: Slice #(N-1) ]========+
| Slice #(N-1) | SEP counter=N-2
| (part 1/r) | P counter=0
: : M=0, T=0, K=1, L=0, I=00
+---------------------------------------+
: :
+---------------------------------------+
| Slice #(N-1) | SEP counter=N-2
| (part r/r) | P counter=r-1
: + EOC marker : M=1, T=0, K=1, L=1, I=00
+=======================================+
Figure 8: Example of JPEG XS Payload Data (slice packetization mode,
progressive frame)
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+====[ PU #1: JPEG XS Hdr segment 1 ]===+
| Video support box | SEP counter=0x07FF
+- - - - - - - - - - - - - - - - - - - -+ P counter=0
| Colour specification box |
+- - - - - - - - - - - - - - - - - - - -+
| JPEG XS codestream header 1 |
| +---------------------------------+ |
| : Markers and marker segments : |
| +---------------------------------+ | M=0, T=0, K=1, L=1, I=10
+====[ PU #2: Slice #1 (1st field) ]====+
| +---------------------------------+ | SEP counter=0
| | SLH Marker | | P counter=0
| +---------------------------------+ |
| : Entropy Coded Data : |
| +---------------------------------+ | M=0, T=0, K=1, L=1, I=10
+====[ PU #3: Slice #2 (1st field) ]====+
| Slice #2 | SEP counter=1
| (part 1/q) | P counter=0
: : M=0, T=0, K=1, L=0, I=10
+---------------------------------------+
| Slice #2 | SEP counter=1
| (part 2/q) | P counter=1
: : M=0, T=0, K=1, L=0, I=10
+---------------------------------------+
: :
+---------------------------------------+
| Slice #2 | SEP counter=1
| (part q/q) | P counter=q-1
: : M=0, T=0, K=1, L=1, I=10
+=======================================+
: :
+==[ PU #N: Slice #(N-1) (1st field) ]==+
| Slice #(N-1) | SEP counter=N-2
| (part 1/r) | P counter=0
: : M=0, T=0, K=1, L=0, I=10
+---------------------------------------+
: :
+---------------------------------------+
| Slice #(N-1) | SEP counter=N-2
| (part r/r) | P counter=r-1
: + EOC marker : M=1, T=0, K=1, L=1, I=10
+=======================================+
+===[ PU #N+1: JPEG XS Hdr segment 2 ]==+
| Video support box | SEP counter=0x07FF
+- - - - - - - - - - - - - - - - - - - -+ P counter=0
| Colour specification box |
+- - - - - - - - - - - - - - - - - - - -+
| JPEG XS codestream header 2 |
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| +---------------------------------+ |
| : Markers and marker segments : |
| +---------------------------------+ | M=0, T=0, K=1, L=1, I=11
+===[ PU #N+2: Slice #1 (2nd field) ]===+
| +---------------------------------+ | SEP counter=0
| | SLH Marker | | P counter=0
| +---------------------------------+ |
| : Entropy Coded Data : |
| +---------------------------------+ | M=0, T=0, K=1, L=1, I=11
+===[ PU #N+3: Slice #2 (2nd field) ]===+
| Slice #2 | SEP counter=1
| (part 1/s) | P counter=0
: : M=0, T=0, K=1, L=0, I=11
+---------------------------------------+
| Slice #2 | SEP counter=1
| (part 2/s) | P counter=1
: : M=0, T=0, K=1, L=0, I=11
+---------------------------------------+
: :
+---------------------------------------+
| Slice #2 | SEP counter=1
| (part s/s) | P counter=s-1
: : M=0, T=0, K=1, L=1, I=11
+=======================================+
: :
+==[ PU #2N: Slice #(N-1) (2nd field) ]=+
| Slice #(N-1) | SEP counter=N-2
| (part 1/t) | P counter=0
: : M=0, T=0, K=1, L=0, I=11
+---------------------------------------+
: :
+---------------------------------------+
| Slice #(N-1) | SEP counter=N-2
| (part t/t) | P counter=t-1
: + EOC marker : M=1, T=0, K=1, L=1, I=11
+=======================================+
Figure 9: Example of JPEG XS Payload Data (slice packetization mode,
interlaced frame)
5. Traffic Shaping and Delivery Timing
In order to facilitate proper synchronization between senders and
receivers it is RECOMMENDED to implement traffic shaping and delivery
timing in accordance with the Network Compatibility Model compliance
definitions specified in [SMPTE-ST2110-21] for either Narrow Senders
(Type N), Narrow Linear Senders (Type NL), or Wide Senders (Type W).
In such case, the session description SHALL include a format-specific
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parameter of either TP=2110TPN, TP=2110TPNL, or TP=2110TPW to
indicate compliance with Type N, Type NL, or Type W respectively.
The actual applied traffic shaping and timing delivery mechanism is
outside the scope of this memo and does not influence the payload
packetization.
NOTE: The Virtual Receiver Buffer Model compliance definitions of
[SMPTE-ST2110-21] do not apply.
6. Congestion Control Considerations
Congestion control for RTP SHALL be used in accordance with
[RFC3550], and with any applicable RTP profile: e.g., [RFC3551]. An
additional requirement if best-effort service is being used is users
of this payload format SHALL monitor packet loss to ensure that the
packet loss rate is within acceptable parameters. Circuit Breakers
[RFC8083] is an update to RTP [RFC3550] that defines criteria for
when one is required to stop sending RTP Packet Streams and
applications implementing this standard SHALL comply with it.
[RFC8085] provides additional information on the best practices for
applying congestion control to UDP streams.
7. Payload Format Parameters
This section specifies the required and optional parameters of the
payload format and/or the RTP stream. All parameters are
declarative, meaning that the information signaled by the parameters
is also present in the payload data, namely in the payload header
(see Section 4.3) or in the JPEG XS header segment [ISO21122-1]
[ISO21122-3]. When provided, their respective values SHALL be
consistent with the payload.
7.1. Media Type Registration
This registration is done using the template defined in [RFC6838]
and following [RFC4855].
The receiver SHALL ignore any unrecognized parameter.
Type name: video
Subtype name: jxsv
Clock rate: 90000
Required parameters:
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rate: The RTP timestamp clock rate. Applications using this
payload format SHALL use a value of 90000.
transmode: This parameter specifies the configured transmission
mode as defined by the Transmission mode (T) bit in the payload
header of Section 4.3. This value SHALL be equal to the T bit
value configured in the RTP stream (i.e. 0 for out-of-order-
allowed or 1 for sequential).
Optional parameters:
packetmode: This parameter specifies the configured packetization
mode as defined by the pacKetization mode (K) bit in the
payload header of Section 4.3. If specified, this value SHALL
be equal to the K bit value configured in the RTP stream (i.e.
0 for codestream or 1 for slice).
profile: The JPEG XS profile [ISO21122-2] in use. Any white
space in the profile name SHALL be omitted. Examples of valid
profile names are 'Main444.12' or 'High444.12'.
level: The JPEG XS level [ISO21122-2] in use. Any white space in
the level name SHALL be omitted. Examples of valid levels
names are '2k-1' or '4k-2'.
sublevel: The JPEG XS sublevel [ISO21122-2] in use. Any white
space in the sublevel name SHALL be omitted. Examples of valid
sublevels are 'Sublev3bpp' or 'Sublev6bpp'.
depth: Determines the number of bits per sample. This is an
integer with typical values including 8, 10, 12, and 16.
width: Determines the number of pixels per line. This is an
integer between 1 and 32767.
height: Determines the number of lines per frame. This is an
integer between 1 and 32767.
exactframerate: Signals the frame rate in frames per second.
Integer frame rates SHALL be signaled as a single decimal
number (e.g. "25") whilst non-integer frame rates SHALL be
signaled as a ratio of two integer decimal numbers separated by
a "forward-slash" character (e.g. "30000/1001"), utilizing the
numerically smallest numerator value possible.
interlace: If this parameter name is present, it indicates that
the video is interlaced, or that the video is Progressive
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segmented Frame (PsF). If this parameter name is not present,
the progressive video format SHALL be assumed.
segmented: If this parameter name is present, and the interlace
parameter name is also present, then the video is a Progressive
segmented Frame (PsF). Signaling of this parameter without the
interlace parameter is forbidden.
sampling: Signals the colour difference signal sub-sampling
structure.
Signals utilizing the non-constant luminance Y'C'B C'R signal
format of Recommendation ITU-R BT.601-7, Recommendation ITU-R
BT.709-6, Recommendation ITU-R BT.2020-2, or Recommendation
ITU-R BT.2100 SHALL use the appropriate one of the following
values for the Media Type Parameter "sampling":
YCbCr-4:4:4 (4:4:4 sampling)
YCbCr-4:2:2 (4:2:2 sampling)
YCbCr-4:2:0 (4:2:0 sampling)
Signals utilizing the Constant Luminance Y'C C'BC C'RC signal
format of Recommendation ITU-R BT.2020-2 SHALL use the
appropriate one of the following values for the Media Type
Parameter "sampling":
CLYCbCr-4:4:4 (4:4:4 sampling)
CLYCbCr-4:2:2 (4:2:2 sampling)
CLYCbCr-4:2:0 (4:2:0 sampling)
Signals utilizing the constant intensity I CT CP signal format
of Recommendation ITU-R BT.2100 SHALL use the appropriate one
of the following values for the Media Type Parameter
"sampling":
ICtCp-4:4:4 (4:4:4 sampling)
ICtCp-4:2:2 (4:2:2 sampling)
ICtCp-4:2:0 (4:2:0 sampling)
Signals utilizing the 4:4:4 R' G' B' or RGB signal format (such
as that of Recommendation ITU-R BT.601, Recommendation ITU-R
BT.709, Recommendation ITU-R BT.2020, Recommendation ITU-R
BT.2100, SMPTE ST 2065-1 or ST 2065-3) SHALL use the following
value for the Media Type Parameter sampling.
RGB (RGB or R' G' B' samples)
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Signals utilizing the 4:4:4 X' Y' Z' signal format (such as
defined in SMPTE ST 428-1) SHALL use the following value for
the Media Type Parameter sampling.
XYZ (X' Y' Z' samples)
Key signals as defined in SMPTE RP 157 SHALL use the value key
for the Media Type Parameter sampling. The Key signal is
represented as a single component.
KEY (Samples of the key signal)
Signals utilizing a colour sub-sampling other than what is
defined here SHALL use the following value for the Media Type
Parameter sampling.
UNSPECIFIED (Sampling signaled by the payload.)
colorimetry: Specifies the system colorimetry used by the image
samples. Valid values and their specification are:
BT601-5 ITU-R Recommendation BT.601-5.
BT709-2 ITU-R Recommendation BT.709-2.
SMPTE240M SMPTE ST 240M.
BT601 ITU-R Recommendation BT.601-7.
BT709 ITU-R Recommendation BT.709-6.
BT2020 ITU-R Recommendation BT.2020-2.
BT2100 ITU-R Recommendation BT.2100
Table 2 titled "System colorimetry".
ST2065-1 SMPTE ST 2065-1 Academy Color Encoding
Specification (ACES).
ST2065-3 SMPTE ST 2065-3 Academy Density Exchange
Encoding (ADX).
XYZ ISO/IEC 11664-1, section titled
"1931 Observer".
UNSPECIFIED Colorimetry is signaled in the payload by
the color specification box of [ISO21122-3],
or it must be manually coordinated between
sender and receiver.
Signals utilizing the Recommendation ITU-R BT.2100 colorimetry
SHOULD also signal the representational range using the
optional parameter RANGE defined below. Signals utilizing the
UNSPECIFIED colorimetry might require manual coordination
between the sender and the receiver.
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TCS: Transfer Characteristic System. This parameter specifies
the transfer characteristic system of the image samples. Valid
values and their specification are:
SDR Standard Dynamic Range video streams that
utilize the OETF of ITU-R Recommendation
BT.709 or ITU-R Recommendation BT.2020. Such
streams SHALL be assumed to target the EOTF
specified in ITU-R Recommendation BT.1886.
PQ High dynamic range video streams that utilize
the Perceptual Quantization system of ITU-R
Recommendation BT.2100.
HLG High dynamic range video streams that utilize
the Hybrid Log-Gamma system of ITU-R
Recommendation BT.2100.
UNSPECIFIED Video streams whose transfer characteristics
are signaled by the payload as specified in
[ISO21122-3], or must be manually
coordinated between sender and receiver.
RANGE: This parameter SHOULD be used to signal the encoding range
of the sample values within the stream. When paired with ITU
Rec BT.2100 colorimetry, this parameter has two allowed values
NARROW and FULL, corresponding to the ranges specified in table
9 of ITU Rec BT.2100. In any other context, this parameter has
three allowed values: NARROW, FULLPROTECT, and FULL, which
correspond to the ranges specified in SMPTE RP 2077. In the
absence of this parameter, and for all but the UNSPECIFIED
colorimetry, NARROW SHALL be the assumed value. When paired
with the UNSPECIFIED colorimetry, FULL SHALL be the default
assumed value.
Encoding considerations:
This media type is framed in RTP and contains binary data; see
Section 4.8 in [RFC6838].
Security considerations:
Please see the Security Considerations (Section 10) of RFC XXXX.
Interoperability considerations:
None.
Published specification:
See RFC XXXX and its References section.
Applications that use this media type:
For example: SMPTE ST 2110, Video over IP, Video conferencing,
Broadcast applications.
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Fragment identifier considerations:
N/A.
Additional information:
None.
Person & email address to contact for further information:
S. Lugan <rtp@intopix.com> and Th. Richter <jpeg-xs-
techsupport@iis.fraunhofer.de>.
Intended usage:
COMMON
Restrictions on usage:
This media type depends on RTP framing, and hence is only defined
for transfer via RTP [RFC3550].
Author:
See the Authors' Addresses section of RFC XXXX.
Change controller:
IETF Audio/Video Transport working group delegated from the IESG.
8. SPD Parameters
A mapping of the parameters into the Session Description Protocol
(SDP) [RFC8866] is provided for applications that use SDP.
8.1. Mapping of Payload Type Parameters to SDP
The media type video/jxsv string is mapped to fields in the Session
Description Protocol (SDP) [RFC8866] as follows:
The media type ("video") goes in SDP "m=" as the media name.
The media subtype ("jxsv") goes in SDP "a=rtpmap" as the encoding
name, followed by a slash ("/") and the required parameter "rate"
corresponding to the RTP timestamp clock rate (which for the
payload format defined in this document SHALL be 90000).
The required parameter "transmode" and any of the additional
optional parameters, as described in Section 7.1, go in the SDP
media format description, being the "a=fmtp" attribute (Format
Parameters), by copying them directly from the MIME media type
string as a semicolon-separated list of parameter=value pairs.
All parameters of the media format SHALL correspond to the parameters
of the payload. In case of discrepancies between payload parameter
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values and SDP fields, the values from the payload data SHALL
prevail.
The receiver SHALL ignore any parameter that is not defined in
Section 7.1.
An example SDP mapping for JPEG XS video is as follows:
m=video 30000 RTP/AVP 112
a=rtpmap:112 jxsv/90000
a=fmtp:112 transmode=1;sampling=YCbCr-4:2:2;width=1920;
height=1080;depth=10;colorimetry=BT709;TCS=SDR;
RANGE=FULL;TP=2110TPNL
In this example, a JPEG XS RTP stream is to be sent to UDP
destination port 30000, with an RTP dynamic payload type of 112 and a
media clock rate of 90000 Hz. Note that the "a=fmtp:" line has been
wrapped to fit this page, and will be a single long line in the SDP
file. This example includes the TP parameter (as specified in
Section 5).
8.2. Usage with SDP Offer/Answer Model
When JPEG XS is offered over RTP using SDP in an offer/answer model
[RFC3264] for negotiation for unicast usage, the following
limitations and rules apply:
The "a=fmtp" attribute SHALL be present specifying the required
parameter "transmode" and MAY specify any of the optional
parameters, as described in Section 7.1.
All parameters in the "a=fmtp" attribute indicate sending
capabilities (i.e. properties of the payload).
An answerer of the SDP is required to support all parameters and
values of the parameters provided by the offerer; otherwise, the
answerer SHALL reject the session. It falls on the offerer to use
values that are expected to be supported by the answerer. If the
answerer accepts the session, it SHALL reply with the exact same
parameters values in the "a=fmtp" attribute as it was offered.
The same RTP payload type number used in the offer SHOULD be used
in the answer, as specified in [RFC3264].
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9. IANA Considerations
The IANA is requested to register the media type registration "video/
jxsv" as specified in Section 7.1. The media type is also requested
to be added to the IANA registry for "RTP Payload Format MIME types"
<https://www.iana.org/assignments/rtp-parameters>.
10. Security Considerations
RTP packets using the payload format defined in this memo are subject
to the security considerations discussed in [RFC3550] and in any
applicable RTP profile such as RTP/AVP [RFC3551], RTP/AVPF [RFC4585],
RTP/SAVP [RFC3711], or RTP/SAVPF [RFC5124]. This implies that
confidentiality of the media streams is achieved by encryption.
However, as "Securing the RTP Framework: Why RTP Does Not Mandate a
Single Media Security Solution" [RFC7202] discusses, it is not an RTP
payload format's responsibility to discuss or mandate what solutions
are used to meet the basic security goals like confidentiality,
integrity, and source authenticity for RTP in general. This
responsibility lies on anyone using RTP in an application. They can
find guidance on available security mechanisms and important
considerations in "Options for Securing RTP Sessions" [RFC7201].
Applications SHOULD use one or more appropriate strong security
mechanisms.
Implementations of this RTP payload format need to take appropriate
security considerations into account. It is important for the
decoder to be robust against malicious or malformed payloads and
ensure that they do not cause the decoder to overrun its allocated
memory or otherwise misbehave. An overrun in allocated memory could
lead to arbitrary code execution by an attacker. The same applies to
the encoder, even though problems in encoders are typically rarer.
This payload format and the JPEG XS encoding do not exhibit any
substantial non-uniformity, either in output or in complexity to
perform the decoding operation and thus are unlikely to pose a
denial-of-service threat due to the receipt of pathological
datagrams.
This payload format and the JPEG XS encoding do not contain code that
is executable.
It is important to note that HD or UHDTV JPEG XS-encoded video can
have significant bandwidth requirements (typically more than 1 Gbps
for ultra high-definition video, especially if using high framerate).
This is sufficient to cause potential for denial-of-service if
transmitted onto most currently available Internet paths.
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Accordingly, if best-effort service is being used, users of this
payload format SHALL monitor packet loss to ensure that the packet
loss rate is within acceptable parameters. Packet loss is considered
acceptable if a TCP flow across the same network path, and
experiencing the same network conditions, would achieve an average
throughput, measured on a reasonable timescale, that is not less than
the RTP flow is achieving. This condition can be satisfied by
implementing congestion control mechanisms to adapt the transmission
rate (or the number of layers subscribed for a layered multicast
session), or by arranging for a receiver to leave the session if the
loss rate is unacceptably high.
This payload format may also be used in networks that provide
quality-of-service guarantees. If enhanced service is being used,
receivers SHOULD monitor packet loss to ensure that the service that
was requested is actually being delivered. If it is not, then they
SHOULD assume that they are receiving best-effort service and behave
accordingly.
11. Acknowledgments
The authors would like to thank the following people for their
valuable contributions to this memo: Arnaud Germain, Alexandre
Willeme, Gael Rouvroy, Siegfried Foessel, and Jean-Baptise Lorent.
12. RFC Editor Considerations
Note to RFC Editor: This section may be removed after carrying out
all the instructions of this section.
RFC XXXX is to be replaced by the RFC number this specification
receives when published.
13. References
13.1. Normative References
[ISO21122-1]
International Organization for Standardization (ISO) -
International Electrotechnical Commission (IEC),
"Information technology - JPEG XS low-latency lightweight
image coding system - Part 1: Core coding system", ISO/
IEC IS 21122-1.
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[ISO21122-2]
International Organization for Standardization (ISO) -
International Electrotechnical Commission (IEC),
"Information technology - JPEG XS low-latency lightweight
image coding system - Part 2: Profiles and buffer models",
ISO/IEC IS 21122-2.
[ISO21122-3]
International Organization for Standardization (ISO) -
International Electrotechnical Commission (IEC),
"Information technology - JPEG XS low-latency lightweight
image coding system - Part 3: Transport and container
formats", ISO/IEC IS 21122-3.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC3264] Rosenberg, J. and H. Schulzrinne, "An Offer/Answer Model
with Session Description Protocol (SDP)", RFC 3264,
DOI 10.17487/RFC3264, June 2002,
<https://www.rfc-editor.org/info/rfc3264>.
[RFC3550] Schulzrinne, H., Casner, S., Frederick, R., and V.
Jacobson, "RTP: A Transport Protocol for Real-Time
Applications", STD 64, RFC 3550, DOI 10.17487/RFC3550,
July 2003, <https://www.rfc-editor.org/info/rfc3550>.
[RFC3551] Schulzrinne, H. and S. Casner, "RTP Profile for Audio and
Video Conferences with Minimal Control", STD 65, RFC 3551,
DOI 10.17487/RFC3551, July 2003,
<https://www.rfc-editor.org/info/rfc3551>.
[RFC4855] Casner, S., "Media Type Registration of RTP Payload
Formats", RFC 4855, DOI 10.17487/RFC4855, February 2007,
<https://www.rfc-editor.org/info/rfc4855>.
[RFC6838] Freed, N., Klensin, J., and T. Hansen, "Media Type
Specifications and Registration Procedures", BCP 13,
RFC 6838, DOI 10.17487/RFC6838, January 2013,
<https://www.rfc-editor.org/info/rfc6838>.
[RFC8083] Perkins, C. and V. Singh, "Multimedia Congestion Control:
Circuit Breakers for Unicast RTP Sessions", RFC 8083,
DOI 10.17487/RFC8083, March 2017,
<https://www.rfc-editor.org/info/rfc8083>.
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[RFC8085] Eggert, L., Fairhurst, G., and G. Shepherd, "UDP Usage
Guidelines", BCP 145, RFC 8085, DOI 10.17487/RFC8085,
March 2017, <https://www.rfc-editor.org/info/rfc8085>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8866] Begen, A., Kyzivat, P., Perkins, C., and M. Handley, "SDP:
Session Description Protocol", RFC 8866,
DOI 10.17487/RFC8866, January 2021,
<https://www.rfc-editor.org/info/rfc8866>.
13.2. Informative References
[RFC3711] Baugher, M., McGrew, D., Naslund, M., Carrara, E., and K.
Norrman, "The Secure Real-time Transport Protocol (SRTP)",
RFC 3711, DOI 10.17487/RFC3711, March 2004,
<https://www.rfc-editor.org/info/rfc3711>.
[RFC4175] Gharai, L. and C. Perkins, "RTP Payload Format for
Uncompressed Video", RFC 4175, DOI 10.17487/RFC4175,
September 2005, <https://www.rfc-editor.org/info/rfc4175>.
[RFC4585] Ott, J., Wenger, S., Sato, N., Burmeister, C., and J. Rey,
"Extended RTP Profile for Real-time Transport Control
Protocol (RTCP)-Based Feedback (RTP/AVPF)", RFC 4585,
DOI 10.17487/RFC4585, July 2006,
<https://www.rfc-editor.org/info/rfc4585>.
[RFC5124] Ott, J. and E. Carrara, "Extended Secure RTP Profile for
Real-time Transport Control Protocol (RTCP)-Based Feedback
(RTP/SAVPF)", RFC 5124, DOI 10.17487/RFC5124, February
2008, <https://www.rfc-editor.org/info/rfc5124>.
[RFC7201] Westerlund, M. and C. Perkins, "Options for Securing RTP
Sessions", RFC 7201, DOI 10.17487/RFC7201, April 2014,
<https://www.rfc-editor.org/info/rfc7201>.
[RFC7202] Perkins, C. and M. Westerlund, "Securing the RTP
Framework: Why RTP Does Not Mandate a Single Media
Security Solution", RFC 7202, DOI 10.17487/RFC7202, April
2014, <https://www.rfc-editor.org/info/rfc7202>.
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[SMPTE-ST2110-21]
Society of Motion Picture and Television Engineers, "SMPTE
Standard - Professional Media Over Managed IP Networks:
Traffic Shaping and Delivery Timing for Video", SMPTE ST
2110-21:2017, 2017,
<https://doi.org/10.5594/SMPTE.ST2110-21.2017>.
Authors' Addresses
Sebastien Lugan
intoPIX S.A.
Rue Emile Francqui, 9
1435 Mont-Saint-Guibert
Belgium
Phone: +32 10 23 84 70
Email: rtp@intopix.com
URI: https://www.intopix.com/
Antonin Descampe
Universite catholique de Louvain
Place du Levant, 3 - bte L5.03.02
1348 Louvain-la-Neuve
Belgium
Phone: +32 10 47 25 97
Email: antonin.descampe@uclouvain.be
URI: https://uclouvain.be/en/research-institutes/icteam
Corentin Damman
intoPIX S.A.
Rue Emile Francqui, 9
1435 Mont-Saint-Guibert
Belgium
Phone: +32 10 23 84 70
Email: c.damman@intopix.com
URI: https://www.intopix.com/
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Thomas Richter
Fraunhofer IIS
Am Wolfsmantel 33
91048 Erlangen
Germany
Phone: +49 9131 776 5126
Email: thomas.richter@iis.fraunhofer.de
URI: https://www.iis.fraunhofer.de/
Tim Bruylants
intoPIX S.A.
Rue Emile Francqui, 9
1435 Mont-Saint-Guibert
Belgium
Phone: +32 10 23 84 70
Email: t.bruylants@intopix.com
URI: https://www.intopix.com/
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