RTP Payload Format for ISO/IEC 21122 (JPEG XS)
draft-bruylants-avtcore-rtp-jpegxs-3ed-00
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| Document | Type | Active Internet-Draft (individual) | |
|---|---|---|---|
| Authors | Tim Bruylants , Thomas Richter , Corentin Damman | ||
| Last updated | 2025-04-08 | ||
| Replaces | draft-bruylants-payload-rtp-jpegxs-3ed | ||
| RFC stream | (None) | ||
| Intended RFC status | (None) | ||
| Formats | |||
| Stream | Stream state | (No stream defined) | |
| Consensus boilerplate | Unknown | ||
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draft-bruylants-avtcore-rtp-jpegxs-3ed-00
avtcore T. Bruylants
Internet-Draft intoPIX
Obsoletes: 9134 (if approved) T. Richter
Intended status: Standards Track Fraunhofer IIS
Expires: 10 October 2025 C. Damman
intoPIX
8 April 2025
RTP Payload Format for ISO/IEC 21122 (JPEG XS)
draft-bruylants-avtcore-rtp-jpegxs-3ed-00
Abstract
This document specifies a Real-Time Transport Protocol (RTP) payload
format to be used for transporting video encoded with JPEG XS (ISO/
IEC 21122). JPEG XS is a low-latency, lightweight image coding
system. Compared to an uncompressed video use case, it allows higher
resolutions and video frame rates while offering visually lossless
quality, reduced power consumption, and encoding-decoding latency
confined to a fraction of a video frame.
This document is a necessary revision of RFC9134 to add support for
new features introduced by the 3rd edition of JPEG XS. It obsoletes
RFC9134 but the revised payload format is designed such that existing
compliant implementations of RFC9134 remain valid to the updated
payload format. In addition, this document integrates the errata of
RFC9134 and provides improvements and clarifications to the text
where applicable.
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 10 October 2025.
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Copyright Notice
Copyright (c) 2025 IETF Trust and the persons identified as the
document authors. All rights reserved.
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 Revised BSD License text as
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provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions, Definitions, and Abbreviations . . . . . . . . . 3
3. Media Format Description . . . . . . . . . . . . . . . . . . 5
3.1. Image Data Structures . . . . . . . . . . . . . . . . . . 5
3.2. Codestream . . . . . . . . . . . . . . . . . . . . . . . 6
3.3. Video Support Box and Color Specification Box . . . . . . 6
3.4. JPEG XS Frame . . . . . . . . . . . . . . . . . . . . . . 7
4. RTP Payload Format . . . . . . . . . . . . . . . . . . . . . 7
4.1. RTP Packetization . . . . . . . . . . . . . . . . . . . . 8
4.2. RTP Header Usage . . . . . . . . . . . . . . . . . . . . 10
4.3. Payload Header Usage . . . . . . . . . . . . . . . . . . 11
4.4. Payload Data . . . . . . . . . . . . . . . . . . . . . . 14
5. Traffic Shaping and Delivery Timing . . . . . . . . . . . . . 19
6. Congestion Control Considerations . . . . . . . . . . . . . . 20
7. Payload Format Parameters . . . . . . . . . . . . . . . . . . 20
7.1. Media Type Registration . . . . . . . . . . . . . . . . . 20
8. SDP Parameters . . . . . . . . . . . . . . . . . . . . . . . 25
8.1. Mapping of Payload Type Parameters to SDP . . . . . . . . 26
8.2. Usage with SDP Offer/Answer Model . . . . . . . . . . . . 26
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 27
10. Security Considerations . . . . . . . . . . . . . . . . . . . 27
11. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 28
12. References . . . . . . . . . . . . . . . . . . . . . . . . . 28
12.1. Normative References . . . . . . . . . . . . . . . . . . 29
12.2. Informative References . . . . . . . . . . . . . . . . . 30
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 32
1. Introduction
This document specifies a payload format for packetization of video
signals encoded with JPEG XS [ISO21122-1] into the Real-time
Transport Protocol (RTP) [RFC3550].
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The JPEG XS coding system offers compression and recompression of
image sequences with very moderate computational resources while
remaining robust under multiple compression and decompression cycles
as well as 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 latency that is introduced
by the encoding-decoding process can be confined to a fraction of a
video frame, typically between a small number of lines down to below
a single line.
This document is a necessary revision of [RFC9134] to add support for
new features introduced by the 3rd edition of JPEG XS. It obsoletes
[RFC9134] but the revised payload format is designed such that
existing compliant implementations of [RFC9134] remain valid to the
updated payload format. In addition, this document integrates the
errata of [RFC9134] and provides improvements and clarifications to
the text where applicable.
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. In this RTP payload definition, it corresponds to a single
JPEG XS video frame.
Color Specification (CS) box:
An ISO color specification box defined in [ISO21122-3] that
includes color-related metadata required to correctly display JPEG
XS video frames, such as color primaries, transfer
characteristics, and matrix coefficients.
End of Codestream (EOC) marker:
A marker that consists of the two bytes 0xff11 indicating the end
of a JPEG XS codestream, as defined in [ISO21122-1].
JPEG XS codestream:
A sequence of bytes representing a compressed image formatted
according to [ISO21122-1].
JPEG XS codestream header:
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A sequence of bytes, starting with an 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 video frame dimension and component precision.
JPEG XS frame:
In the case of progressive video, a single JPEG XS picture
segment. In the case of interlaced video, the concatenation of
two JPEG XS picture segments.
JPEG XS header segment:
The concatenation of a video support box [ISO21122-3], a color
specification box [ISO21122-3], and a JPEG XS codestream header.
JPEG XS picture segment:
The concatenation of a video support box [ISO21122-3], a color
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 ADU whose boundaries coincide with boundaries of
RTP packet payloads (excluding payload header), i.e., the first
(or respectively, last) byte of a packetization unit is the first
(or respectively, last) byte of an RTP packet payload (excluding
its payload header).
SLH (Slice header) marker:
A marker that represents a slice header, as defined in
[ISO21122-1].
SLI (TDC enabling slice header) marker:
A marker that represents a TDC enabling slice header, as defined
in [ISO21122-1].
Slice:
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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.
Start of a Codestream (SOC) marker:
A marker that consists of the two bytes 0xff10 indicating the
start of a JPEG XS codestream, as defined in [ISO21122-1]. The
SOC marker is considered an integral part of the JPEG XS
codestream header.
Temporal Differential Coding (TDC):
An inter-frame coding mode used by certain JPEG XS profiles, as
defined in [ISO21122-2].
Video Support (VS) box:
An ISO video support box, as defined in [ISO21122-3], that
includes metadata required to play back a JPEG XS stream; such
metadata could include its maximum bit rate, its subsampling
structure, its buffer model, and its frame rate.
3. Media Format Description
This section explains the terminology and concepts used in this memo
specific to JPEG XS as specified in [ISO21122-1], [ISO21122-2], and
[ISO21122-3].
3.1. Image Data Structures
JPEG XS is a low-latency, lightweight image coding system for coding
continuous-tone grayscale or continuous-tone color 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.
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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 of each other.
However, note 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 is formed by (in the given order):
* a JPEG XS codestream header, which starts with a Start of
Codestream (SOC) marker,
* one or more slices,
* an EOC marker to signal the end of the 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
color space.
3.3. Video Support Box and Color 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 color
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 bit rate,
the frame rate, the interlaced mode (progressive or interlaced), the
subsampling image format, the informative timecode of the current
JPEG XS frame, the profile, the level/sublevel used, and optionally
the buffer model and the mastering display metadata.
Note that the profile and level/sublevel/fbblevel, specified
respectively by the Ppih and Plev fields [ISO21122-2], 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, sublevel, and (optionally) frame buffer level
defines a lower bound on the required throughput for a decoder in the
image (or decoded) domain and the codestream (or coded) domain,
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respectively. The actual defined profiles and levels/sublevels/
fbblevel, along with the associated values for the Ppih and Plev
fields, are defined in [ISO21122-2].
The color specification box indicates the color primaries, transfer
characteristics, matrix coefficients, and video full range flag
needed to specify the color space of the video stream.
3.4. JPEG XS Frame
The concatenation of a video support box, a color 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., the byte sequence that contains the concatenation of the
video support box and the color specification box is exactly the same
in 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.
Note that the frat field [ISO21122-3] in the video support box always
signals the frame rate, even in the case of interlaced content. This
should not be confused with the field rate.
4. RTP Payload Format
This section specifies the payload format for JPEG XS streams over
the Real-time Transport Protocol (RTP) [RFC3550].
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.
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4.1. RTP Packetization
An ADU is made of several packetization units. If a packetization
unit is bigger than the maximum size of an 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)
with the possible exception of 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 (or, respectively, last) byte of the packetization
unit SHALL be the first (or, respectively, 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.
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.
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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
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
In a constant bitrate (CBR) scenario of JPEG XS, the codestream
packetization mode guarantees that a JPEG XS RTP stream will produce
both a constant number of bytes per video frame and a constant number
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of RTP packets per video frame. However, to provide similar
guarantees with JPEG XS in a variable bitrate (VBR) mode or when
using the slice packetization mode (for either CBR or VBR),
additional mechanisms are needed. This can involve a constraint at
the rate allocation stage in the JPEG XS encoder to impose a CBR at
the slice level, the usage of padding data, or the insertion of empty
RTP packets (i.e., an RTP packet whose payload data is empty). But,
management of the amount of produced packets per video frame is
application dependent and not a strict requirement of this RTP
payload specification.
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.
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=2|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]:
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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]:
The payload type is 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
(see also [RFC3550] and [RFC4175]). A 90 kHz clock rate SHALL be
used. 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.
For progressive scan video, the timestamp denotes the sampling
instant 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.
For interlaced video, the timestamp denotes the sampling instant
of the field to which the RTP packet belongs. Packets SHALL NOT
include data from multiple fields, and all packets belonging to
the same field SHALL have the same timestamp. Use of field
timestamps, rather than a frame timestamp and field indicator bit,
is needed to support reverse 3-2 pulldown.
Several successive RTP packets will consequently have equal
timestamps if they belong to the same video field for interlace
content, or video frame for progressive content. That is, the
time stamp does not change until the marker bit (M) is set to 1,
marking the last packet of the video frame or field. The
timestamp is only increased when a new video field or video frame
begins.
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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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. The T bit value SHALL be identical for all
packets of the RTP stream.
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 (out of order), the slice packetization mode SHALL
be used and K SHALL be set to 1. This is required because only
the slice packetization mode supports out-of-order packet
transmission. The K bit value SHALL be identical for all packets
of the RTP stream.
Last (L) [1 bit]:
The L bit is set to indicate the last packet of a packetization
unit. As the end of the video frame also ends the packet
containing the last unit of the video frame, the L bit is set
whenever the M bit is set. In the codestream packetization mode,
the L bit and M bit get an equivalent meaning, so they SHALL have
identical values in each packet.
Interlaced information (I) [2 bits]:
These two I 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: This value is 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.
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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 video frame number modulo 32
to which a packet belongs. Frame numbers SHALL increment by 1 for
each video 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. For interlaced
frames, both fields SHALL have the same F counter value.
Slice and Extended Packet (SEP) counter [11 bits]:
The 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
Section 4.4) 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 video frame).
P counter [11 bits]:
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.
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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 color 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, in the
same order. With the exception of the value of the Tcod field in the
Video Information box [ISO21122-3], the effective values in the boxes
SHALL be identical across all JPEG XS frames of the RTP stream.
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 video frame in the codestream packetization mode,
Figure 7 depicts this layout for an interlaced video frame in the
codestream packetization mode, Figure 8 depicts this layout for a
progressive video frame in the slice packetization mode, and Figure 9
depicts this layout for an interlaced video frame in the slice
packetization mode. The Frame (F) counter value is not indicated
because the value is constant for all packetization units of a given
video frame.
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+=====[ Packetization unit (PU) #1 ]====+
| Video support box | SEP counter=0
| +---------------------------------+ | P counter=0
| : Sub boxes of the VS box : |
| +---------------------------------+ |
+- - - - - - - - - - - - - - - - - - - -+
| Color 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 using Codestream
Packetization Mode with Progressive Video Frames
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+=====[ Packetization unit (PU) #1 ]====+
| Video support box | SEP counter=0
+- - - - - - - - - - - - - - - - - - - -+ P counter=0
| Color 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
| Color 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 using Codestream
Packetization Mode with Interlaced Video Frames
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+===[ PU #1: JPEG XS Header segment ]===+
| Video support box | SEP counter=0x07FF
+- - - - - - - - - - - - - - - - - - - -+ P counter=0
| Color 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 or SLI 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 using Slice
Packetization Mode with Progressive Video Frames
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+====[ PU #1: JPEG XS Hdr segment 1 ]===+
| Video support box | SEP counter=0x07FF
+- - - - - - - - - - - - - - - - - - - -+ P counter=0
| Color 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 or SLI 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
| Color 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 or SLI 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 using Slice
Packetization Mode with Interlaced Video Frames
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 [SMPTE2110-21]. In such a case,
the session description SHALL signal the compliance with the media
type parameter TP. The actual applied traffic shaping and timing
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delivery mechanism is outside the scope of this memo and does not
influence the payload packetization.
6. Congestion Control Considerations
Congestion control for RTP SHALL be used in accordance with [RFC3550]
and with any applicable RTP profile, e.g., RTP/AVP [RFC3551] or RTP/
AVPF [RFC4585].
While JPEG XS is mainly designed to be used in controlled network
environments, it can also be employed in best-effort network
environments, like the Internet. However, in this case, the users of
this payload format SHALL monitor packet loss to ensure that the
packet loss rate is within acceptable parameters. This can be
achieved, for example, by means of RTP Control Protocol (RTCP)
Feedback for Congestion Control [RFC8888].
In addition, [RFC8083] is an update to [RFC3550] that defines
criteria for when one is required to stop sending RTP Packet Streams
and for when 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
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Required parameters:
rate: The RTP timestamp clock rate. Applications using this
payload format SHALL use a value of 90000.
packetmode: This parameter specifies the configured packetization
mode as defined by the pacKetization mode (K) bit in the
payload header of Section 4.3. This value SHALL be equal to
the K-bit value configured in the RTP stream (i.e., 0 for
codestream or 1 for slice).
Optional parameters:
transmode: This parameter specifies the configured transmission
mode as defined by the Transmission mode (T) bit in the payload
header of Section 4.3. If specified, 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-only). If not
specified, a value 1 (sequential-only) SHALL be assumed and the
T bit SHALL be set to 1.
profile: The JPEG XS profile [ISO21122-2] in use. Any white
space Unicode character in the profile name SHALL be omitted.
Examples of valid profile names are 'Main444.12', 'High444.12',
'CHigh444.12', or 'TDC444.12'.
level: The JPEG XS level [ISO21122-2] in use. Any white space
Unicode character in the level name SHALL be omitted. Examples
of valid levels are '2k-1' or '4k-2'.
sublevel: The JPEG XS sublevel [ISO21122-2] in use. Any white
space Unicode character in the sublevel name SHALL be omitted.
Examples of valid sublevels are 'Sublev3bpp' or 'Sublev6bpp'.
fbblevel: The JPEG XS frame buffer level [ISO21122-2] in use.
Any white space Unicode character in the fbblevel name SHALL be
omitted. Examples of valid frame buffer levels are
'Fbblev3bpp' or 'Fbblev12bpp'.
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, inclusive.
height: Determines the number of lines per video frame. This is
an integer between 1 and 32767, inclusive.
exactframerate: Signals the video frame rate in frames per
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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
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 color difference signal sub-sampling
structure.
Signals utilizing the non-constant luminance Y'C'B C'R signal
format of [BT601-7], [BT709-6], [BT2020-2], or [BT2100-2] 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 [BT2020-2] 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 [BT2100-2] 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)
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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 [BT601-7], [BT709-6], [BT2020-2], [BT2100-2],
[SMPTE2065-1], or [SMPTE2065-3]) SHALL use the following value
for the Media Type Parameter "sampling":
RGB (RGB or R' G' B' samples)
Signals utilizing the 4:4:4 X' Y' Z' signal format (such as
defined in [SMPTE428-1]) SHALL use the following value for the
Media Type Parameter "sampling":
XYZ (X' Y' Z' samples)
Key signals as defined in [SMPTE157] 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 color 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 the
following:
BT601-5: [BT601-5].
BT709-2: [BT709-2].
SMPTE240M: [SMPTE240M].
BT601: [BT601-7].
BT709: [BT709-6].
BT2020: [BT2020-2].
BT2100: [BT2100-2], Table 2 titled "System colorimetry".
ST2065-1: Academy Color Encoding Specification (ACES)
[SMPTE2065-1].
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ST2065-3: Academy Density Exchange Encoding (ADX)
[SMPTE2065-3].
XYZ: [ISO11664-1], 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 [BT2100-2] 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.
TCS: Transfer Characteristic System. This parameter specifies
the transfer characteristic system of the image samples. Valid
values and their specification are the following:
SDR: Standard Dynamic Range video streams that utilize the
Optical Electrical Transfer Function (OETF) of [BT709-6] or
[BT2020-2]. Such streams SHALL be assumed to target the
Electro-Optical Transfer Function (EOTF) specified in
[BT1886-0].
PQ: High dynamic range video streams that utilize the
Perceptual Quantization system of [BT2100-2].
HLG: High dynamic range video streams that utilize the Hybrid
Log-Gamma system of [BT2100-2].
UNSPECIFIED: Video streams whose transfer characteristics are
signaled by the payload as specified in [ISO21122-3], or
that 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
[BT2100-2] colorimetry, this parameter has two allowed values,
NARROW and FULL, corresponding to the ranges specified in TABLE
9 of [BT2100-2]. In any other context, this parameter has
three allowed values: NARROW, FULLPROTECT, and FULL, which
correspond to the ranges specified in [SMPTE2077]. 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.
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Encoding considerations:
This media type is framed in RTP and contains binary data; see
Section 4.8 of [RFC6838].
Security considerations:
See the Security Considerations section of [RFCXXXX].
Interoperability considerations:
None
Published specification:
See the References section of [RFCXXXX]
Applications that use this media type:
Any application that transmits video over RTP (like SMPTE ST
2110).
Fragment identifier considerations:
N/A
Additional information:
None
Person & email address to contact for further information:
T. Bruylants rtp@intopix.com (mailto:rtp@intopix.com) and T.
Richter jpeg-xs-techsupport@iis.fraunhofer.de (mailto:jpeg-xs-
techsupport@iis.fraunhofer.de).
Intended usage:
COMMON
Restrictions on usage:
This media type depends on RTP framing; hence, it is only defined
for transfer via RTP [RFC3550].
Author:
See the Authors' Addresses section of [RFCXXXX].
Change controller:
IETF Audio/Video Transport Working Group delegated from the IESG.
8. SDP Parameters
A mapping of the parameters into the Session Description Protocol
(SDP) [RFC8866] is provided for applications that use SDP.
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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 "packetmode" 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 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
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 packetmode=0;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:
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The "a=fmtp" attribute SHALL be present specifying the required
parameter "packetmode" 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
parameter values in the "a=fmtp" attribute as they were initially
offered.
The same RTP payload type number used in the offer SHOULD be used in
the answer, as specified in [RFC3264].
9. IANA Considerations
IANA has registered the media type registration "video/jxsv" as
specified in Section 7.1. The media type has also been added to the
IANA registry for "RTP Payload Format Media Types" (see
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
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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; thus, they 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 high-definition (HD) or ultra-high-
definition (UHD) video that is encoded with JPEG XS can have
significant bandwidth requirements (typically more than 1 Gbps for
UHD video, especially if using high framerate). This is sufficient
to cause potential for denial of service if transmitted onto most
currently available Internet paths.
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 that made this memo possible: Antonin
Descampe, Siegfried Foessel, Arnaud Germain, Jean-Baptise Lorent,
Sébastien Lugan, Gaël Rouvroy, and Alexandre Willème.
12. References
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12.1. Normative References
[ISO21122-1]
ISO/IEC, "Information technology - JPEG XS low-latency
lightweight image coding system - Part 1: Core coding
system", ISO/IEC IS 21122-1.
[ISO21122-2]
ISO/IEC, "Information technology - JPEG XS low-latency
lightweight image coding system - Part 2: Profiles and
buffer models", ISO/IEC IS 21122-2.
[ISO21122-3]
ISO/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/rfc/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/rfc/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/rfc/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/rfc/rfc3551>.
[RFC4855] Casner, S., "Media Type Registration of RTP Payload
Formats", RFC 4855, DOI 10.17487/RFC4855, February 2007,
<https://www.rfc-editor.org/rfc/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/rfc/rfc6838>.
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[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/rfc/rfc8083>.
[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/rfc/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/rfc/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/rfc/rfc8866>.
12.2. Informative References
[BT1886-0] ITU-R, "Reference electro-optical transfer function for
flat panel displays used in HDTV studio production",
ITU-R Recommendation BT.1886-0, March 2011,
<https://www.itu.int/rec/R-REC-BT.1886-0-201103-I/en>.
[BT2020-2] ITU-R, "Parameter values for ultra-high definition
television systems for production and international
programme exchange", ITU-R Recommendation BT.2020-2,
October 2015,
<https://www.itu.int/rec/R-REC-BT.2020-2-201510-I/en>.
[BT2100-2] ITU-R, "Image parameter values for high dynamic range
television for use in production and international
programme exchange", ITU-R Recommendation BT.2100-2, July
2018,
<https://www.itu.int/rec/R-REC-BT.2100-2-201807-I/en>.
[BT601-5] ITU-R, "Studio encoding parameters of digital television
for standard 4:3 and wide screen 16:9 aspect ratios",
ITU-R Recommendation BT.601-5, October 1995,
<https://www.itu.int/rec/R-REC-BT.601-5-199510-S/en>.
[BT601-7] ITU-R, "Studio encoding parameters of digital television
for standard 4:3 and wide screen 16:9 aspect ratios",
ITU-R Recommendation BT.601-7, March 2011,
<https://www.itu.int/rec/R-REC-BT.601-7-201103-I/en>.
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[BT709-2] ITU-R, "Parameter values for the HDTV standards for
production and international programme exchange",
ITU-R Recommendation BT.709-2, October 1995,
<https://www.itu.int/rec/R-REC-BT.709-2-199510-S/en>.
[BT709-6] ITU-R, "Parameter values for the HDTV standards for
production and international programme exchange",
ITU-R Recommendation BT.709-6, June 2015,
<https://www.itu.int/rec/R-REC-BT.709-6-201506-I/en>.
[ISO11664-1]
ISO/CIE, "Colorimetry - Part 1: CIE standard colorimetric
observers", ISO/CIE IS 11664-1:2019, June 2019,
<https://www.iso.org/standard/74164.html>.
[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/rfc/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/rfc/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/rfc/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/rfc/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/rfc/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/rfc/rfc7202>.
[RFC8888] Sarker, Z., Perkins, C., Singh, V., and M. Ramalho, "RTP
Control Protocol (RTCP) Feedback for Congestion Control",
RFC 8888, DOI 10.17487/RFC8888, January 2021,
<https://www.rfc-editor.org/rfc/rfc8888>.
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[RFC9134] Bruylants, T., Descampe, A., Damman, C., and T. Richter,
"RTP Payload Format for ISO/IEC 21122 (JPEG XS)",
RFC 9134, DOI 10.17487/RFC9134, October 2021,
<https://www.rfc-editor.org/rfc/rfc9134>.
[SMPTE157] SMPTE, "SMPTE Recommended Practice - Key and Alpha
Signals", SMPTE RP 157:2012, November 2012.
[SMPTE2065-1]
SMPTE, "SMPTE Standard - Academy Color Encoding
Specification (ACES)", SMPTE ST 2065-1:2021,
DOI 10.5594/SMPTE.ST2065-1.2021, January 2021,
<https://doi.org/10.5594/SMPTE.ST2065-1.2021>.
[SMPTE2065-3]
SMPTE, "SMPTE Standard - Academy Density Exchange Encoding
(ADX) - Encoding Academy Printing Density (APD) Values",
SMPTE ST 2065-3:2020, DOI 10.5594/SMPTE.ST2065-3.2020,
November 2020,
<https://doi.org/10.5594/SMPTE.ST2065-3.2020>.
[SMPTE2077]
SMPTE, "SMPTE Recommended Practice - Full-Range Image
Mapping", SMPTE RP 2077:2013,
DOI 10.5594/SMPTE.RP2077.2013, November 2013,
<https://doi.org/10.5594/SMPTE.RP2077.2013>.
[SMPTE2110-21]
SMPTE, "SMPTE Standard - Professional Media Over Managed
IP Networks: Traffic Shaping and Delivery Timing for
Video", SMPTE ST 2110-21:2017,
DOI 10.5594/SMPTE.ST2110-21.2017, November 2017,
<https://doi.org/10.5594/SMPTE.ST2110-21.2017>.
[SMPTE240M]
SMPTE, "SMPTE Standard - For Television - 1125-Line High-
Definition Production Systems - Signal Parameters",
SMPTE ST 240M:1999, DOI 10.5594/SMPTE.ST240.1999, November
1999, <https://doi.org/10.5594/SMPTE.ST240.1999>.
[SMPTE428-1]
SMPTE, "SMPTE Standard - D-Cinema Distribution Master -
Image Characteristics", SMPTE ST 428-1:2019,
DOI 10.5594/SMPTE.ST428-1.2019, March 2019,
<https://doi.org/10.5594/SMPTE.ST428-1.2019>.
Authors' Addresses
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Tim Bruylants
intoPIX S.A.
Rue Emile Francqui 9
B-1435 Mont-Saint-Guibert
Belgium
Phone: +32 10 23 84 70
Email: t.bruylants@intopix.com
URI: https://www.intopix.com/
Thomas Richter
Fraunhofer IIS
Am Wolfsmantel 33
D-91058 Erlangen
Germany
Phone: +49 9131 776 5126
Email: thomas.richter@iis.fraunhofer.de
URI: https://www.iis.fraunhofer.de/
Corentin Damman
intoPIX S.A.
Rue Emile Francqui 9
B-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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