MPEG news: a report from the 135th meeting (virtual)

The original blog post can be found at the Bitmovin Techblog and has been modified/updated here to focus on and highlight research aspects. Additionally, this version of the blog post will also be posted at ACM SIGMM Records.

MPEG News Archive

The 135th MPEG meeting was once again held as an online meeting, and the official press release can be found here and comprises the following items:

• MPEG Video Coding promotes MPEG Immersive Video (MIV) to the FDIS stage
• Verification tests for more application cases of Versatile Video Coding (VVC)
• MPEG Systems reaches first milestone for Video Decoding Interface for Immersive Media
• MPEG Systems further enhances the extensibility and flexibility of Network-based Media Processing
• MPEG Systems completes support of Versatile Video Coding and Essential Video Coding in High Efficiency Image File Format
• Two MPEG White Papers:
  • Versatile Video Coding (VVC)
  • MPEG-G and its application of regulation and privacy

In this column, I’d like to focus on MIV and VVC including systems-related aspects as well as a brief update about DASH (as usual).

MPEG Immersive Video (MIV)

At the 135^th MPEG meeting, MPEG Video Coding has promoted the MPEG Immersive Video (MIV) standard to the Final Draft International Standard (FDIS) stage. MIV was developed to support compression of immersive video content in which multiple real or virtual cameras capture a real or virtual 3D scene. The standard enables storage and distribution of immersive video content over existing and future networks for playback with 6 Degrees of Freedom (6DoF) of view position and orientation.

From a technical point of view, MIV is a flexible standard for multiview video with depth (MVD) that leverages the strong hardware support for commonly used video codecs to code volumetric video. The actual views may choose from three projection formats: (i) equirectangular, (ii) perspective, or (iii) orthographic. By packing and pruning views, MIV can achieve bit rates around 25 Mb/s and a pixel rate equivalent to HEVC Level 5.2.

The MIV standard is designed as a set of extensions and profile restrictions for the Visual Volumetric Video-based Coding (V3C) standard (ISO/IEC 23090-5). The main body of this standard is shared between MIV and the Video-based Point Cloud Coding (V-PCC) standard (ISO/IEC 23090-5 Annex H). It may potentially be used by other MPEG-I volumetric codecs under development. The carriage of MIV is specified through the Carriage of V3C Data standard (ISO/IEC 23090-10).

The test model and objective metrics are publicly available at https://gitlab.com/mpeg-i-visual.

At the same time, MPEG Systems has begun developing the Video Decoding Interface for Immersive Media (VDI) standard (ISO/IEC 23090-13) for a video decoders’ input and output interfaces to provide more flexible use of the video decoder resources for such applications. At the 135th MPEG meeting, MPEG Systems has reached the first formal milestone of developing the ISO/IEC 23090-13 standard by promoting the text to Committee Draft ballot status. The VDI standard allows for dynamic adaptation of video bitstreams to provide the decoded output pictures in such a way so that the number of actual video decoders can be smaller than the number of the elementary video streams to be decoded. In other cases, virtual instances of video decoders can be associated with the portions of elementary streams required to be decoded. With this standard, the resource requirements of a platform running multiple virtual video decoder instances can be further optimized by considering the specific decoded video regions that are to be actually presented to the users rather than considering only the number of video elementary streams in use.

Research aspects: It seems that visual compression and systems standards enabling immersive media applications and services are becoming mature. However, the Quality of Experience (QoE) of such applications and services is still in its infancy. The QUALINET White Paper on Definitions of Immersive Media Experience (IMEx) provides a survey of definitions of immersion and presence which leads to a definition of Immersive Media Experience (IMEx). Consequently, the next step is working towards QoE metrics in this domain that requires subjective quality assessments imposing various challenges during the current COVID-19 pandemic.

Versatile Video Coding (VVC) updates

The third round of verification testing for Versatile Video Coding (VVC) has been completed. This includes the testing of High Dynamic Range (HDR) content of 4K ultra-high-definition (UHD) resolution using the Hybrid Log-Gamma (HLG) and Perceptual Quantization (PQ) video formats. The test was conducted using state-of-the-art high-quality consumer displays, emulating an internet streaming-type scenario.

On average, VVC showed on average approximately 50% bit rate reduction compared to High Efficiency Video Coding (HEVC).

Additionally, the ISO/IEC 23008-12 Image File Format has been amended to support images coded using Versatile Video Coding (VVC) and Essential Video Coding (EVC).

Research aspects: The results of the verification tests are usually publicly available and can be used as a baseline for future improvements of the respective standards including the evaluation thereof. For example, the tradeoff compression efficiency vs. encoding runtime (time complexity) for live and video on-demand scenarios is always an interesting research aspect.

The latest MPEG-DASH Update

Finally, I’d like to provide a brief update on MPEG-DASH! At the 135^th MPEG meeting, MPEG Systems issued a draft amendment to the core MPEG-DASH specification (i.e., ISO/IEC 23009-1) that provides further improvements of Preroll which is renamed to Preperiod and it will be further discussed during the Ad-hoc Group (AhG) period (please join the dash email list for further details/announcements). Additionally, this amendment includes some minor improvements for nonlinear playback. The so-called Technologies under Consideration (TuC) document comprises new proposals that did not yet reach consensus for promotion to any official standards documents (e.g., amendments to existing DASH standards or new parts). Currently, proposals for minimizing initial delay are discussed among others. Finally, libdash has been updated to support the MPEG-DASH schema according to the 5th edition.

An updated overview of DASH standards/features can be found in the Figure below.

MPEG-DASH status of July 2021.

Research aspects: The informative aspects of MPEG-DASH such as the adaptive bitrate (ABR) algorithms have been subject to research for many years. New editions of the standard mostly introduced incremental improvements but disruptive ideas rarely reached the surface. Perhaps it's time to take a step back and re-think how streaming should work for todays and future media applications and services.

The 136th MPEG meeting will be again an online meeting in October 2021 but MPEG is aiming to meet in-person again in January 2021 (if possible). Click here for more information about MPEG meetings and their developments.

MPEG news: a report from the 133rd meeting (virtual)

The original blog post can be found at the Bitmovin Techblog and has been modified/updated to focus on and highlight research aspects. Additionally, this version of the blog post will also be posted at ACM SIGMM Records.

MPEG News Archive

MPEG Systems File Format Subgroup wins Technology & Engineering Emmy® Award

The 133rd MPEG meeting was once again held as an online meeting, and this time, kicked off with great news, that MPEG is one of the organizations honored as a 72nd Annual Technology & Engineering Emmy® Awards Recipient, specifically the MPEG Systems File Format Subgroup and its ISO Base Media File Format (ISOBMFF) et al.

The official press release can be found here and comprises the following items:

• 6th Emmy® Award for MPEG Technology: MPEG Systems File Format Subgroup wins Technology & Engineering Emmy® Award
• Essential Video Coding (EVC) verification test finalized
• MPEG issues a Call for Evidence on Video Coding for Machines
• Neural Network Compression for Multimedia Applications – MPEG calls for technologies for incremental coding of neural networks
• MPEG Systems reaches the first milestone for supporting Versatile Video Coding (VVC) and Essential Video Coding (EVC) in the Common Media Application Format (CMAF)
• MPEG Systems continuously enhances Dynamic Adaptive Streaming over HTTP (DASH)
• MPEG Systems reached the first milestone to carry event messages in tracks of the ISO Base Media File Format

In this report, I’d like to focus on ISOBMFF, EVC, CMAF, and DASH.

MPEG Systems File Format Subgroup wins Technology & Engineering Emmy® Award

MPEG is pleased to report that the File Format subgroup of MPEG Systems is being recognized this year by the National Academy for Television Arts and Sciences (NATAS) with a Technology & Engineering Emmy® for their 20 years of work on the ISO Base Media File Format (ISOBMFF). This format was first standardized in 1999 as part of the MPEG-4 Systems specification and is now in its 6th edition as ISO/IEC 14496-12. It has been used and adopted by many other specifications, e.g.:

• MP4 and 3GP file formats;
• Carriage of NAL unit structured video in the ISO Base Media File Format, which provides support for AVC, HEVC, VVC, EVC, and probably soon LCEVC;
• MPEG-21 file format;
• Dynamic Adaptive Streaming over HTTP (DASH) and Common Media Application Format (CMAF);
• High-Efficiency Image Format (HEIF);
• Timed text and other visual overlays in ISOBMFF;
• Common encryption format;
• Carriage of timed metadata metrics of media;
• Derived visual tracks;
• Event message track format;
• Carriage of uncompressed video;
• Omnidirectional Media Format (OMAF);
• Carriage of visual volumetric video-based coding data;
• Carriage of geometry-based point cloud compression data;
• … to be continued!

This is MPEG’s fourth Technology & Engineering Emmy® Award (after MPEG-1 and MPEG-2 together with JPEG in 1996, Advanced Video Coding (AVC) in 2008, and MPEG-2 Transport Stream in 2013) and sixth overall Emmy® Award, including the Primetime Engineering Emmy® Awards for Advanced Video Coding (AVC) High Profile in 2008 and High-Efficiency Video Coding (HEVC) in 2017, respectively.

Essential Video Coding (EVC) verification test finalized

At the 133rd MPEG meeting, a verification testing assessment of the Essential Video Coding (EVC) standard was completed. The first part of the EVC verification test using high dynamic range (HDR) and wide color gamut (WCG) was completed at the 132nd MPEG meeting. A subjective quality evaluation was conducted comparing the EVC Main profile to the HEVC Main 10 profile and the EVC Baseline profile to AVC High 10 profile, respectively:

• Analysis of the subjective test results showed that the average bitrate savings for EVC Main profile are approximately 40% compared to HEVC Main 10 profile, using UHD and HD SDR content encoded in both random access and low delay configurations.
• The average bitrate savings for the EVC Baseline profile compared to the AVC High 10 profile is approximately 40% using UHD SDR content encoded in the random-access configuration and approximately 35% using HD SDR content encoded in the low delay configuration.
• Verification test results using HDR content had shown average bitrate savings for EVC Main profile of approximately 35% compared to HEVC Main 10 profile.

By providing significantly improved compression efficiency compared to HEVC and earlier video coding standards while encouraging the timely publication of licensing terms, the MPEG-5 EVC standard is expected to meet the market needs of emerging delivery protocols and networks, such as 5G, enabling the delivery of high-quality video services to an ever-growing audience.

In addition to verification tests, EVC, along with VVC and CMAF were subject to further improvements to their support systems.

Research aspects: as for every new video codec, its compression efficiency and computational complexity are important performance metrics. Additionally, the availability of (efficient) open-source implementations (i.e., x264, x265, soon x266, VVenC, aomenc, et al., etc.) are vital for its adoption in the (academic) research community.

MPEG Systems reaches the first milestone for supporting Versatile Video Coding (VVC) and Essential Video Coding (EVC) in the Common Media Application Format (CMAF)

At the 133rd MPEG meeting, MPEG Systems promoted Amendment 2 of the Common Media Application Format (CMAF) to Committee Draft Amendment (CDAM) status, the first major milestone in the ISO/IEC approval process. This amendment defines:

• constraints to (i) Versatile Video Coding (VVC) and (ii) Essential Video Coding (EVC) video elementary streams when carried in a CMAF video track;
• codec parameters to be used for CMAF switching sets with VVC and EVC tracks; and
• support of the newly introduced MPEG-H 3D Audio profile.

It is expected to reach its final milestone in early 2022. For research aspects related to CMAF, the reader is referred to the next section about DASH.

MPEG Systems continuously enhances Dynamic Adaptive Streaming over HTTP (DASH)

At the 133rd MPEG meeting, MPEG Systems promoted Part 8 of Dynamic Adaptive Streaming over HTTP (DASH), also referred to as “Session-based DASH,” to its final stage of standardization (i.e., Final Draft International Standard (FDIS)).

Historically, in DASH, every client uses the same Media Presentation Description (MPD), as it best serves the service's scalability. However, there have been increasing requests from the industry to enable customized manifests for enabling personalized services. MPEG Systems has standardized a solution to this problem without sacrificing scalability. Session-based DASH adds a mechanism to the MPD to refer to another document, called Session-based Description (SBD), allowing per-session information. The DASH client can use this information (i.e., variables and their values) provided in the SBD to derive the URLs for HTTP GET requests.

An updated overview of DASH standards/features can be found in the Figure below.

MPEG DASH Status as of January 2021.

Research aspects: CMAF is mostly like becoming the main segment format to be used in the context of HTTP adaptive streaming (HAS) and, thus, also DASH (hence also the name common media application format). Supporting a plethora of media coding formats will inevitably result in a multi-codec dilemma that needs to be addressed soon as there will be no flag day where everyone will switch to a new coding format. Thus, designing efficient bitrate ladders for multi-codec delivery will an interesting research aspect, which needs to include device/player support (i.e., some devices/player will support only a subset of available codecs), storage capacity/costs within the cloud as well as within the delivery network, and network distribution capacity/costs (i.e., CDN costs).

The 134th MPEG meeting will be again an online meeting in April 2021. Click here for more information about MPEG meetings and their developments.

MPEG news: a report from the 132nd meeting (virtual)

The original blog post can be found at the Bitmovin Techblog and has been modified/updated here to focus on and highlight research aspects. Additionally, this version of the blog post will be also posted at ACM SIGMM Records.

MPEG News Archive

The 132nd MPEG meeting was the first meeting with the new structure. That is, ISO/IEC JTC 1/SC 29/WG 11 -- the official name of MPEG under the ISO structure -- was disbanded after the 131st MPEG meeting and some of the subgroups of WG 11 (MPEG) have been elevated to independent MPEG Working Groups (WGs) and Advisory Groups (AGs) of SC 29 rather than subgroups of the former WG 11. Thus, the MPEG community is now an affiliated group of WGs and AGs that will continue meeting together according to previous MPEG meeting practices and will further advance the standardization activities of the MPEG work program.

The 132nd MPEG meeting was the first meeting with the new structure as follows (incl. Convenors and position within WG 11 structure):

• AG 2 MPEG Technical Coordination (Convenor: Prof. Jörn Ostermann; for overall MPEG work coordination and prev. known as the MPEG chairs meeting; it’s expected that one can also provide inputs to this AG without being a member of this AG)
• WG 2 MPEG Technical Requirements (Convenor Dr. Igor Curcio; former Requirements subgroup)
• WG 3 MPEG Systems (Convenor: Dr. Youngkwon Lim; former Systems subgroup)
• WG 4 MPEG Video Coding (Convenor: Prof. Lu Yu; former Video subgroup)
• WG 5 MPEG Joint Video Coding Team(s) with ITU-T SG 16 (Convenor: Prof. Jens-Rainer Ohm; former JVET)
• WG 6 MPEG Audio Coding (Convenor: Dr. Schuyler Quackenbush; former Audio subgroup)
• WG 7 MPEG Coding of 3D Graphics (Convenor: Prof. Marius Preda, former 3DG subgroup)
• WG 8 MPEG Genome Coding (Convenor: Prof. Marco Mattaveli; newly established WG)
• AG 3 MPEG Liaison and Communication (Convenor: Prof. Kyuheon Kim; (former Communications subgroup)
• AG 5 MPEG Visual Quality Assessment (Convenor: Prof. Mathias Wien; former Test subgroup).

The 132nd MPEG meeting was held as an online meeting and more than 300 participants continued to work efficiently on standards for the future needs of the industry. As a group, MPEG started to explore new application areas that will benefit from standardized compression technology in the future. A new web site has been created and can be found at http://mpeg.org/.

The official press release can be found here and comprises the following items:

• Versatile Video Coding (VVC) Ultra-HD Verification Test Completed and Conformance and Reference Software Standards Reach their First Milestone
• MPEG Completes Geometry-based Point Cloud Compression (G-PCC) Standard
• MPEG Evaluates Extensions and Improvements to MPEG-G and Announces a Call for Evidence on New Advanced Genomics Features and Technologies
• MPEG Issues Draft Call for Proposals on the Coded Representation of Haptics
• MPEG Evaluates Responses to MPEG IPR Smart Contracts CfP
• MPEG Completes Standard on Harmonization of DASH and CMAF
• MPEG Completes 2nd Edition of the Omnidirectional Media Format (OMAF)
• MPEG Completes the Low Complexity Enhancement Video Coding (LCEVC) Standard

In this report, I’d like to focus on VVC, G-PCC, DASH/CMAF, OMAF, and LCEVC.

Versatile Video Coding (VVC) Ultra-HD Verification Test Completed and Conformance & Reference Software Standards Reach their First Milestone

MPEG completed a verification testing assessment of the recently ratified Versatile Video Coding (VVC) standard for ultra-high definition (UHD) content with standard dynamic range, as may be used in newer streaming and broadcast television applications. The verification test was performed using rigorous subjective quality assessment methods and showed that VVC provides a compelling gain over its predecessor -- the High Efficiency Video Coding (HEVC) standard produced in 2013. In particular, the verification test was performed using the VVC reference software implementation (VTM) and the recently released open-source encoder implementation of VVC (VVenC):

• Using its reference software implementation (VTM), VVC showed bit rate savings of roughly 45% over HEVC for comparable subjective video quality.
• Using VVenC, additional bit rate savings of more than 10% relative to VTM were observed, which at the same time runs significantly faster than the reference software implementation.

Additionally, the standardization work for both conformance testing and reference software for the VVC standard reached its first major milestone, i.e., progressing to the Committee Draft ballot in the ISO/IEC approval process. The conformance testing standard (ISO/IEC 23090-15) will ensure interoperability among the diverse applications that use the VVC standard, and the reference software standard (ISO/IEC 23090-16) will provide an illustration of the capabilities of VVC and a valuable example showing how the standard can be implemented. The reference software will further facilitate the adoption of the standard by being available for use as the basis of product implementations.

Research aspects: as for every new video codec, its compression efficiency and computational complexity are important performance metrics. While the reference software (VTM) provides a valid reference in terms of compression efficiency it is not optimized for runtime. VVenC seems to provide already a significant improvement and with x266 another open source implementation will be available soon. Together with AOMedia's AV1 (including its possible successor AV2) we are looking forward to a lively future in the area of video codecs.

MPEG Completes Geometry-based Point Cloud Compression Standard

MPEG promoted its ISO/IEC 23090-9 Geometry-based Point Cloud Compression (G-PCC) standard to the Final Draft International Standard (FDIS) stage. G-PCC addresses lossless and lossy coding of time-varying 3D point clouds with associated attributes such as color and material properties. This technology is particularly suitable for sparse point clouds. ISO/IEC 23090-5 Video-based Point Cloud Compression (V-PCC), which reached the FDIS stage in July 2020, addresses the same problem but for dense point clouds, by projecting the (typically dense) 3D point clouds onto planes, and then processing the resulting sequences of 2D images using video compression techniques. The generalized approach of G-PCC, where the 3D geometry is directly coded to exploit any redundancy in the point cloud itself, is complementary to V-PCC and particularly useful for sparse point clouds representing large environments.

Point clouds are typically represented by extremely large amounts of data, which is a significant barrier to mass-market applications. However, the relative ease of capturing and rendering spatial information compared to other volumetric video representations makes point clouds increasingly popular for displaying immersive volumetric data. The current draft reference software implementation of a lossless, intra-frame G‐PCC encoder provides a compression ratio of up to 10:1 and lossy coding of acceptable quality for a variety of applications with a ratio of up to 35:1.

By providing high immersion at currently available bit rates, the G‐PCC standard will enable various applications such as 3D mapping, indoor navigation, autonomous driving, advanced augmented reality (AR) with environmental mapping, and cultural heritage.

Research aspects: the main research focus related to G-PCC and V-PCC is currently on compression efficiency but one should not dismiss its delivery aspects including its dynamic, adaptive streaming. A recent paper on this topic has been published in the IEEE Communications Magazine and is entitled "From Capturing to Rendering: Volumetric Media Delivery With Six Degrees of Freedom".

MPEG Finalizes the Harmonization of DASH and CMAF

MPEG successfully completed the harmonization of Dynamic Adaptive Streaming over HTTP (DASH) with Common Media Application Format (CMAF) featuring a DASH profile for the use with CMAF (as part of the 1st Amendment of ISO/IEC 23009-1:2019 4th edition).

CMAF and DASH segments are both based on the ISO Base Media File Format (ISOBMFF), which per se enables smooth integration of both technologies. Most importantly, this DASH profile defines (a) a normative mapping of CMAF structures to DASH structures and (b) how to use Media Presentation Description (MPD) as a manifest format.

Additional tools added to this amendment include

• DASH events and timed metadata track timing and processing models with in-band event streams,
• a method for specifying the resynchronization points of segments when the segments have internal structures that allow container-level resynchronization,
• an MPD patch framework that allows the transmission of partial MPD information as opposed to the complete MPD using the XML patch framework as defined in IETF RFC 5261, and
• content protection enhancements for efficient signaling.

It is expected that the 5th edition of the MPEG DASH standard (ISO/IEC 23009-1) containing this change will be issued at the 133rd MPEG meeting in January 2021. An overview of DASH standards/features can be found in the Figure below.

Research aspects: one of the features enabled by CMAF is low latency streaming that is actively researched within the multimedia systems community (e.g., here). The main research focus has been related to the ABR logic while its impact on the network is not yet fully understood and requires strong collaboration among stakeholders along the delivery path including ingest, encoding, packaging, (encryption), content delivery network (CDN), and consumption. A holistic view on ABR is needed to enable innovation and the next step towards the future generation of streaming technologies (https://athena.itec.aau.at/). 

MPEG Completes 2nd Edition of the Omnidirectional Media Format

MPEG completed the standardization of the 2nd edition of the Omnidirectional MediA Format (OMAF) by promoting ISO/IEC 23009-2 to Final Draft International Standard (FDIS) status including the following features:

• “Late binding” technologies to deliver and present only that part of the content that adapts to the dynamically changing users' viewpoint. To enable an efficient implementation of such a feature, this edition of the specification introduces the concept of bitstream rewriting, in which a compliant bitstream is dynamically generated that, by combining the received portions of the bitstream, covers only the users' viewport on the client.
• Extension of OMAF beyond 360-degree video. This edition introduces the concept of viewpoints, which can be considered as user-switchable camera positions for viewing content or as temporally contiguous parts of a storyline to provide multiple choices for the storyline a user can follow.
• Enhances the use of video, image, or timed text overlays on top of omnidirectional visual background video or images related to a sphere or a viewport.

Research aspects: standards usually define formats to enable interoperability but various informative aspects are left open for industry competition and subject to research and development. The same holds for OMAF and its 2nd edition enables researchers and developers to work towards efficient viewport-adaptive implementations focusing on the users' viewport.

MPEG Completes the Low Complexity Enhancement Video Coding Standard

MPEG is pleased to announce the completion of the new ISO/IEC 23094-2 standard, i.e., Low Complexity Enhancement Video Coding (MPEG-5 Part 2 LCEVC), which has been promoted to Final Draft International Standard (FDIS) at the 132nd MPEG meeting.

• LCEVC adds an enhancement data stream that can appreciably improve the resolution and visual quality of reconstructed video with an effective compression efficiency of limited complexity by building on top of existing and future video codecs.
• LCEVC can be used to complement devices originally designed only for decoding the base layer bitstream, by using firmware, operating system, or browser support. It is designed to be compatible with existing video workflows (e.g., CDNs, metadata management, DRM/CA) and network protocols (e.g., HLS, DASH, CMAF) to facilitate the rapid deployment of enhanced video services.
• LCEVC can be used to deliver higher video quality in limited bandwidth scenarios, especially when the available bit rate is low for high-resolution video delivery and decoding complexity is a challenge. Typical use cases include mobile streaming and social media, and services that benefit from high-density/low-power transcoding.

Research aspects: LCEVC provides a kind of scalable video coding by combining hardware- and software-based decoders that allows for a certain flexibility as part of regular software life cycle updates. However, LCEVC has been never compared to Scalable Video Coding (SVC) and Scalable High Efficiency Video Coding (SHVC) which could be an interesting aspect for future work.

The 133rd MPEG meeting will be again an online meeting in January 2021.

Click here for more information about MPEG meetings and their developments.

MPEG news: a report from the 131st meeting (virtual)

The original blog post can be found at the Bitmovin Techblog and has been modified/updated here to focus on and highlight research aspects. Additionally, this version of the blog post will be also posted at ACM SIGMM Records.

MPEG News Archive

The 131st MPEG meeting concluded on July 3, 2020, online, again but with a press release comprising an impressive list of news items which is led by

MPEG Announces VVC – the Versatile Video Coding Standard

Just in the middle of the SC29 (i.e., MPEG’s parent body within ISO) restructuring process, MPEG successfully ratified -- jointly with ITU-T’s VCEG within JVET -- its next-generation video codec among other interesting results from the 131st MPEG meeting:

Standards progressing to final approval ballot (FDIS)

• MPEG Announces VVC – the Versatile Video Coding Standard
• Point Cloud Compression – MPEG promotes a Video-based Point Cloud Compression Technology to the FDIS stage
• MPEG-H 3D Audio – MPEG promotes Baseline Profile for 3D Audio to the final stage

Call for Proposals

• Call for Proposals on Technologies for MPEG-21 Contracts to Smart Contracts Conversion
• MPEG issues a Call for Proposals on extension and improvements to ISO/IEC 23092 standard series

Standards progressing to the first milestone of the ISO standard development process

• Widening support for storage and delivery of MPEG-5 EVC
• Multi-Image Application Format adds support of HDR
• Carriage of Geometry-based Point Cloud Data progresses to Committee Draft
• MPEG Immersive Video (MIV) progresses to Committee Draft
• Neural Network Compression for Multimedia Applications – MPEG progresses to Committee Draft
• MPEG issues Committee Draft of Conformance and Reference Software for Essential Video Coding (EVC)

The corresponding press release of the 131st MPEG meeting can be found here: https://mpeg-standards.com/meetings/mpeg-131/. This report focused on video coding featuring VVC as well as PCC and systems aspects (i.e., file format, DASH).

MPEG Announces VVC – the Versatile Video Coding Standard

MPEG is pleased to announce the completion of the new Versatile Video Coding (VVC) standard at its 131st meeting. The document has been progressed to its final approval ballot as ISO/IEC 23090-3 and will also be known as H.266 in the ITU-T.

VVC Architecture (from IEEE ICME 2020 tutorial of Mathias Wien and Benjamin Bross)

VVC is the latest in a series of very successful standards for video coding that have been jointly developed with ITU-T, and it is the direct successor to the well-known and widely used High Efficiency Video Coding (HEVC) and Advanced Video Coding (AVC) standards (see architecture in the figure above). VVC provides a major benefit in compression over HEVC. Plans are underway to conduct a verification test with formal subjective testing to confirm that VVC achieves an estimated 50% bit rate reduction versus HEVC for equal subjective video quality. Test results have already demonstrated that VVC typically provides about a 40%-bit rate reduction for 4K/UHD video sequences in tests using objective metrics (i.e., PSNR, VMAF, MS-SSIM). Application areas especially targeted for the use of VVC include

• ultra-high definition 4K and 8K video,
• video with a high dynamic range and wide colour gamut, and
• video for immersive media applications such as 360° omnidirectional video.

Furthermore, VVC is designed for a wide variety of types of video such as camera captured, computer-generated, and mixed content for screen sharing, adaptive streaming, game streaming, video with scrolling text, etc. Conventional standard-definition and high-definition video content are also supported with similar gains in compression. In addition to improving coding efficiency, VVC also provides highly flexible syntax supporting such use cases as (i) subpicture bitstream extraction, (ii) bitstream merging, (iii) temporal sublayering, and (iv) layered coding scalability.

The current performance of VVC compared to HEVC-HM is shown in the figure below which confirms the statement above but also highlights the increased complexity. Please note that VTM9 is not optimized for speed but functionality (i.e., compression efficiency).

Performance of VVC, VTM9 vs. HM (taken from https://bit.ly/mpeg131).

MPEG also announces completion of ISO/IEC 23002-7 “Versatile supplemental enhancement information for coded video bitstreams” (VSEI), developed jointly with ITU-T as Rec. ITU-T H.274. The new VSEI standard specifies the syntax and semantics of video usability information (VUI) parameters and supplemental enhancement information (SEI) messages for use with coded video bitstreams. VSEI is especially intended for use with VVC, although it is drafted to be generic and flexible so that it may also be used with other types of coded video bitstreams. Once specified in VSEI, different video coding standards and systems-environment specifications can re-use the same SEI messages without the need for defining special-purpose data customized to the specific usage context.

At the same time, the Media Coding Industry Forum (MC-IF) announces a VVC patent pool fostering with an initial meeting on September 1, 2020. The aim of this meeting is to identify tasks and to propose a schedule for VVC pool fostering with the goal to select a pool facilitator/administrator by the end of 2020. MC-IF is not facilitating or administering a patent pool.

At the time of writing this blog post, it is probably too early to make an assessment of whether VVC will share the fate of HEVC or AVC (w.r.t. patent pooling). AVC is still the most widely used video codec but with AVC, HEVC, EVC, VVC, LCEVC, AV1, (AV2), and probably also AVS3 -- did I miss anything? -- the competition and pressure are certainly increasing.

Research aspects: from a research perspective, reduction of time-complexity (for a variety of use cases) while maintaining quality and bitrate at acceptable levels is probably the most relevant aspect. Improvements in individual building blocks of VVC by using artificial neural networks (ANNs) are another area of interest but also end-to-end aspects of video coding using ANNs will probably pave the roads towards the/a next generation of video codec(s). Utilizing VVC and its features for HTTP adaptive streaming (HAS) is probably most interesting for me but maybe also for others...

MPEG promotes a Video-based Point Cloud Compression Technology to the FDIS stage

At its 131st meeting, MPEG promoted its Video-based Point Cloud Compression (V-PCC) standard to the Final Draft International Standard (FDIS) stage. V-PCC addresses lossless and lossy coding of 3D point clouds with associated attributes such as colors and reflectance. Point clouds are typically represented by extremely large amounts of data, which is a significant barrier for mass-market applications. However, the relative ease to capture and render spatial information as point clouds compared to other volumetric video representations makes point clouds increasingly popular to present immersive volumetric data. With the current V-PCC encoder implementation providing compression in the range of 100:1 to 300:1, a dynamic point cloud of one million points could be encoded at 8 Mbit/s with good perceptual quality. Real-time decoding and rendering of V-PCC bitstreams have also been demonstrated on current mobile hardware.

The V-PCC standard leverages video compression technologies and the video ecosystem in general (hardware acceleration, transmission services, and infrastructure) while enabling new kinds of applications. The V-PCC standard contains several profiles that leverage existing AVC and HEVC implementations, which may make them suitable to run on existing and emerging platforms. The standard is also extensible to upcoming video specifications such as Versatile Video Coding (VVC) and Essential Video Coding (EVC).

The V-PCC standard is based on Visual Volumetric Video-based Coding (V3C), which is expected to be re-used by other MPEG-I volumetric codecs under development. MPEG is also developing a standard for the carriage of V-PCC and V3C data (ISO/IEC 23090-10) which has been promoted to DIS status at the 130th MPEG meeting.

By providing high-level immersiveness at currently available bandwidths, the V-PCC standard is expected to enable several types of applications and services such as six Degrees of Freedom (6 DoF) immersive media, virtual reality (VR) / augmented reality (AR), immersive real-time communication and cultural heritage.

Research aspects: as V-PCC is video-based, we can probably state similar research aspects as for video codecs such as improving efficiency both for encoding and rendering as well as reduction of time complexity. During the development of V-PCC mainly HEVC (and AVC) has/have been used but it is definitely interesting to use also VVC for PCC. Finally, the dynamic adaptive streaming of V-PCC data is still in its infancy despite some articles published here and there.

MPEG Systems related News

Finally, I’d like to share news related to MPEG systems and the carriage of video data as depicted in the figure below. In particular, the carriage of VVC (and also EVC) has been now enabled in MPEG-2 Systems (specifically within the transport stream) and in the various file formats (specifically within the NAL file format). The latter is used also in CMAF and DASH which makes VVC (and also EVC) ready for HTTP adaptive streaming (HAS).

Carriage of Video in MPEG Systems Standards (taken from https://bit.ly/mpeg131).

What about DASH and CMAF?

CMAF maintains a so-called "technologies under consideration" document which contains -- among other things -- a proposed VVC CMAF profile. Additionally, there are two exploration activities related to CMAF, i.e., (i) multi-stream support and (ii) storage, archiving, and content management for CMAF files.

DASH works on potential improvement for the first amendment to ISO/IEC 23009-1 4th edition related to CMAF support, events processing model, and other extensions. Additionally, there’s a working draft for a second amendment to ISO/IEC 23009-1 4th edition enabling bandwidth change signaling track and other enhancements. Furthermore, ISO/IEC 23009-8 (Session-based DASH operations) has been advanced to Draft International Standard (see also my last report).

An overview of the current status of MPEG-DASH can be found in the figure below.

The next meeting will be again an online meeting in October 2020.

Finally, MPEG organized a Webinar presenting results from the 131st MPEG meeting. The slides and video recordings are available here: https://bit.ly/mpeg131.

Click here for more information about MPEG meetings and their developments.

MPEG131 Press Release: WG11 (MPEG) Announces VVC – the Versatile Video Coding Standard

MPEG131 Press Release: Index

WG11 (MPEG) Announces VVC – the Versatile Video Coding Standard

WG11 (MPEG) is pleased to announce the completion of the new Versatile Video Coding (VVC) standard at its 131st meeting. The document has been progressed to its final approval ballot as ISO/IEC 23090-3 and will also be known as H.266 in the ITU-T.

VVC is the latest in a series of very successful standards for video coding that have been jointly developed with ITU-T, and it is the direct successor to the well-known and widely used HEVC (Rec. ITU-T H.265 | ISO/IEC 23008-2) and AVC (Rec. ITU-T H.264 | ISO/IEC 14496-10) standards. VVC provides a major benefit in compression over HEVC. Plans are underway to conduct a verification test with formal subjective testing to confirm that VVC achieves an estimated 50% bit rate reduction versus HEVC for equal subjective video quality. Test results have already demonstrated that VVC typically provides about a 40%-bit rate reduction for 4K/UHD video sequences in tests using objective metrics. Application areas especially targeted for the use of VVC include ultra-high definition 4K and 8K video, video with a high dynamic range and wide colour gamut, and video for immersive media applications such as 360° omnidirectional video. Conventional standard-definition and high-definition video content are also supported with similar gains in compression. In addition to improving coding efficiency, VVC also provides highly flexible syntax supporting such use cases as subpicture bitstream extraction, bitstream merging, temporal sublayering, and layered coding scalability.

The VVC standard includes the specification of six profiles to serve the needs of the industry in a wide variety of applications. These include the “Main 10” profile that supports 8- and 10-bit 4:2:0 video, the “Main 10 4:4:4” profile with 4:4:4 and 4:2:2 format support, corresponding “Multilayer Main 10” and “Multilayer Main 10 4:4:4” profiles with support for layered coding, and the “Main 10 Still Picture” and “Main 10 4:4:4 Still Picture” profiles for still image coding employing the same coding tools as in the corresponding video profiles.MPEG also announces completion of ISO/IEC 23002-7 “Versatile supplemental enhancement information for coded video bitstreams” (VSEI), developed jointly with ITU-T as Rec. ITU-T H.274. The new VSEI standard specifies the syntax and semantics of video usability information (VUI) parameters and supplemental enhancement information (SEI) messages for use with coded video bitstreams. VSEI is especially intended for use with VVC, although it is drafted to be generic and flexible so that it may also be used with other types of coded video bitstreams. Once specified in VSEI, different video coding standards and systems-environment specifications can re-use the same SEI messages without the need for defining special-purpose data customized to the specific usage context.

MPEG news: a report from the 127th meeting, Gothenburg, Sweden

The original blog post can be found at the Bitmovin Techblog and has been modified/updated here to focus on and highlight research aspects. Additionally, this version of the blog post will be also posted at ACM SIGMM Records.

MPEG News Archive

Plenary of the 127th MPEG Meeting in Gothenburg, Sweden.

The 126th MPEG meeting concluded on March 29, 2019 in Geneva, Switzerland with the following topics:

• Versatile Video Coding (VVC) enters formal approval stage, experts predict 35-60% improvement over HEVC
• Essential Video Coding (EVC) promoted to Committee Draft
• Common Media Application Format (CMAF) 2nd edition promoted to Final Draft International Standard
• Dynamic Adaptive Streaming over HTTP (DASH) 4th edition promoted to Final Draft International Standard
• Carriage of Point Cloud Data Progresses to Committee Draft
• JPEG XS carriage in MPEG-2 TS promoted to Final Draft Amendment of ISO/IEC 13818-1 7th edition
• Genomic information representation – WG11 issues a joint call for proposals on genomic annotations in conjunction with ISO TC 276/WG 5
• ISO/IEC 23005 (MPEG-V) 4th Edition – WG11 promotes the Fourth edition of two parts of “Media Context and Control” to the Final Draft International Standard (FDIS) stage

The corresponding press release of the 127th MPEG meeting can be found here: https://mpeg.chiariglione.org/meetings/127

Versatile Video Coding (VVC)

The Moving Picture Experts Group (MPEG) is pleased to announce that Versatile Video Coding (VVC) progresses to Committee Draft, experts predict 35-60% improvement over HEVC.

The development of the next major generation of video coding standard has achieved excellent progress, such that MPEG has approved the Committee Draft (CD, i.e., the text for formal balloting in the ISO/IEC approval process).

The new VVC standard will be applicable to a very broad range of applications and it will also provide additional functionalities. VVC will provide a substantial improvement in coding efficiency relative to existing standards. The improvement in coding efficiency is expected to be quite substantial – e.g., in the range of 35–60% bit rate reduction relative to HEVC although it has not yet been formally measured. Relative to HEVC means for equivalent subjective video quality at picture resolutions such as 1080p HD or 4K or 8K UHD, either for standard dynamic range video or high dynamic range and wide color gamut content for levels of quality appropriate for use in consumer distribution services. The focus during the development of the standard has primarily been on 10-bit 4:2:0 content, and 4:4:4 chroma format will also be supported.

The VVC standard is being developed in the Joint Video Experts Team (JVET), a group established jointly by MPEG and the Video Coding Experts Group (VCEG) of ITU-T Study Group 16. In addition to a text specification, the project also includes the development of reference software, a conformance testing suite, and a new standard ISO/IEC 23002-7 specifying supplemental enhancement information messages for coded video bitstreams. The approval process for ISO/IEC 23002-7 has also begun, with the issuance of a CD consideration ballot.

Research aspects: VVC represents the next generation video codec to be deployed in 2020+ and basically the same research aspects apply as for previous generations, i.e., coding efficiency, performance/complexity, and objective/subjective evaluation. Luckily, JVET documents are freely available including the actual standard (committee draft), software (and its description), and common test conditions. Thus, researcher utilizing these resources are able to conduct reproducible research when contributing their findings and code improvements back to the community at large. 

Essential Video Coding (EVC)

MPEG-5 Essential Video Coding (EVC) promoted to Committee Draft

Interestingly, at the same meeting as VVC, MPEG promoted MPEG-5 Essential Video Coding (EVC) to Committee Draft (CD). The goal of MPEG-5 EVC is to provide a standardized video coding solution to address business needs in some use cases, such as video streaming, where existing ISO video coding standards have not been as widely adopted as might be expected from their purely technical characteristics.

The MPEG-5 EVC standards includes a baseline profile that contains only technologies that are over 20 years old or are otherwise expected to be royalty-free. Additionally, a main profile adds a small number of additional tools, each providing significant performance gain. All main profile tools are capable of being individually switched off or individually switched over to a corresponding baseline tool. Organizations making proposals for the main profile have agreed to publish applicable licensing terms within two years of FDIS stage, either individually or as part of a patent pool.

Research aspects: Similar research aspects can be described for EVC and from a software engineering perspective it could be also interesting to further investigate this switching mechanism of individual tools or/and fall back option to baseline tools. Naturally, a comparison with next generation codecs such as VVC is interesting per se. The licensing aspects itself are probably interesting for other disciplines but that is another story...

Common Media Application Format (CMAF)

MPEG ratified the 2nd edition of the Common Media Application Format (CMAF)

The Common Media Application Format (CMAF) enables efficient encoding, storage, and delivery of digital media content (incl. audio, video, subtitles among others), which is key to scaling operations to support the rapid growth of video streaming over the internet. The CMAF standard is the result of widespread industry adoption of an application of MPEG technologies for adaptive video streaming over the Internet, and widespread industry participation in the MPEG process to standardize best practices within CMAF.

The 2nd edition of CMAF adds support for a number of specifications that were a result of significant industry interest. Those include

• Advanced Audio Coding (AAC) multi-channel;
• MPEG-H 3D Audio;
• MPEG-D Unified Speech and Audio Coding (USAC);
• Scalable High Efficiency Video Coding (SHVC);
• IMSC 1.1 (Timed Text Markup Language Profiles for Internet Media Subtitles and Captions); and
• additional HEVC video CMAF profiles and brands.

This edition also introduces CMAF supplemental data handling as well as new structural brands for CMAF that reflects the common practice of the significant deployment of CMAF in industry. Companies adopting CMAF technology will find the specifications introduced in the 2nd Edition particularly useful for further adoption and proliferation of CMAF in the market.

Research aspects: see below (DASH).

Dynamic Adaptive Streaming over HTTP (DASH)

MPEG approves the 4th edition of Dynamic Adaptive Streaming over HTTP (DASH)

The 4th edition of MPEG-DASH comprises the following features:

service description that is intended by the service provider on how the service is expected to be consumed;

• a method to indicate the times corresponding to the production of associated media;
• a mechanism to signal DASH profiles and features, employed codec and format profiles; and
• supported protection schemes present in the Media Presentation Description (MPD).

It is expected that this edition will be published later this year. 

Research aspects: CMAF 2nd and DASH 4th edition come along with a rich feature set enabling a plethora of use cases. The underlying principles are still the same and research issues arise from updated application and service requirements with respect to content complexity, time aspects (mainly delay/latency), and quality of experience (QoE). The DASH-IF awards the excellence in DASH award at the ACM Multimedia Systems conference and an overview about its academic efforts can be found here. For example, see here our recent research on bandwidth prediction in low-latency chunked streaming. Additionally, our tutorial at ACM Multimedia 2019 about a journey towards fully immersive media access reviews state of the art in this area and how it could be extended enabling 6DoF HAS services through point cloud compression.

Carriage of Point Cloud Data

MPEG progresses the Carriage of Point Cloud Data to Committee Draft

At its 127th meeting, MPEG has promoted the carriage of point cloud data to the Committee Draft stage, the first milestone of ISO standard development process. This standard is the first one introducing the support of volumetric media in the industry-famous ISO base media file format family of standards.

This standard supports the carriage of point cloud data comprising individually encoded video bitstreams within multiple file format tracks in order to support the intrinsic nature of the video-based point cloud compression (V-PCC). Additionally, it also allows the carriage of point cloud data in one file format track for applications requiring multiplexed content (i.e., the video bitstream of multiple components is interleaved into one bitstream).

This standard is expected to support efficient access and delivery of some portions of a point cloud object considering that in many cases that entire point cloud object may not be visible by the user depending on the viewing direction or location of the point cloud object relative to other objects. It is currently expected that the standard will reach its final milestone by the end of 2020.

Research aspects: MPEG's Point Cloud Compression (PCC) comes in two flavors, video- and geometric-based but still requires to be packaged into file and delivery formats. MPEG's choice here is the ISO base media file format and the efficient carriage of point cloud data is characterized by both functionality (i.e., enabling the required used cases) and performance (such as low overhead).

MPEG 2 Systems/Transport Stream

JPEG XS carriage in MPEG-2 TS promoted to Final Draft Amendment of ISO/IEC 13818-1 7th edition

At its 127th meeting, WG11 (MPEG) has extended ISO/IEC 13818-1 (MPEG-2 Systems) – in collaboration with WG1 (JPEG) – to support ISO/IEC 21122 (JPEG XS) in order to support industries using still image compression technologies for broadcasting infrastructures. The specification defines a JPEG XS elementary stream header and specifies how the JPEG XS video access unit (specified in ISO/IEC 21122-1) is put into a Packetized Elementary Stream (PES). Additionally, the specification also defines how the System Target Decoder (STD) model can be extended to support JPEG XS video elementary streams.

Genomic information representation

WG11 issues a joint call for proposals on genomic annotations in conjunction with ISO TC 276/WG 5

The introduction of high-throughput DNA sequencing has led to the generation of large quantities of genomic sequencing data that have to be stored, transferred and analyzed. So far WG 11 (MPEG) and ISO TC 276/WG 5 have addressed the representation, compression and transport of genome sequencing data by developing the ISO/IEC 23092 standard series also known as MPEG-G. They provide a file and transport format, compression technology, metadata specifications, protection support, and standard APIs for the access of sequencing data in the native compressed format.

An important element in the effective usage of sequencing data is the association of the data with the results of the analysis and annotations that are generated by processing pipelines and analysts. At the moment such association happens as a separate step, standard and effective ways of linking data and meta information derived from sequencing data are not available.

At its 127th meeting, MPEG and ISO TC 276/WG 5 issued a joint Call for Proposals (CfP) addressing the solution of such problem. The call seeks submissions of technologies that can provide efficient representation and compression solutions for the processing of genomic annotation data.

Companies and organizations are invited to submit proposals in response to this call. Responses are expected to be submitted by the 8th January 2020 and will be evaluated during the 129th WG 11 (MPEG) meeting. Detailed information, including how to respond to the call for proposals, the requirements that have to be considered, and the test data to be used, is reported in the documents N18648, N18647, and N18649 available at the 127th meeting website (http://mpeg.chiariglione.org/meetings/127). For any further question about the call, test conditions, required software or test sequences please contact: Joern Ostermann, MPEG Requirements Group Chair (ostermann@tnt.uni-hannover.de) or Martin Golebiewski, Convenor ISO TC 276/WG 5 (martin.golebiewski@h-its.org).

ISO/IEC 23005 (MPEG-V) 4th Edition

WG11 promotes the Fourth edition of two parts of “Media Context and Control” to the Final Draft International Standard (FDIS) stage

At its 127th meeting, WG11 (MPEG) promoted the 4th edition of two parts of ISO/IEC 23005 (MPEG-V; Media Context and Control) standards to the Final Draft International Standard (FDIS). The new edition of ISO/IEC 23005-1 (architecture) enables ten new use cases, which can be grouped into four categories: 3D printing, olfactory information in virtual worlds, virtual panoramic vision in car, and adaptive sound handling. The new edition of ISO/IEC 23005-7 (conformance and reference software) is updated to reflect the changes made by the introduction of new tools defined in other parts of ISO/IEC 23005. More information on MPEG-V and its parts 1-7 can be found at https://mpeg.chiariglione.org/standards/mpeg-v.

Finally, the unofficial highlight of the 127th MPEG meeting we certainly found while scanning the scene in Gothenburg on Tuesday night...

What happened in multimedia communication in 2018?

In January 2018 I wrote a blog post entitled "What to care about in multimedia communication in 2018?" and I think it's worth looking back to see what actually happened with respect to next generation video coding formats and adaptive streaming techniques.

In April 2018, the responses to the call for proposals for the next standard in video compression have been evaluated and a first working draft and test model for the Versatile Video Coding (VVC) standard have been approved. At this point already, some proposals demonstrated compression efficiency gains of typically 40% or more when compared to using HEVC. Currently, working draft 3 and test model 3 of VVC (VTM 3) are available and we may certainly expect compression efficiency gains well-beyond the targeted 50% for the final standard. An overview about VVC can be found here (by C. Feldmann) and here (by M. Wien). The licensing issues have been acknowledged and, thus, the Media Coding Industry Forum (MC-IF) has been established.

At the beginning of 2018, everyone was also very curious about AOMedia and AV1. Version 1 of the specification has been finally become available and in the meantime it is implemented/deployed on both content provisioning/encoding (e.g. Bitmovin) and content consumption/decoding (e.g., Chrome, Firefox). In this context, we also published a multi-codec DASH dataset comprising AVC, HEVC, VP9, and AV1 (VVC will be added at a later stage). In general, however, we are entering the era of multiple video codecs deployed in products and services whereby this trend is also confirmed by Bitmovin's latest video developer survey.

MPEG-DASH 3rd edition has been approved and is awaiting publication but I expect this to happen in 2019 though. An overview of the MPEG-DASH status is shown in the figure below.

In this context, the DASH-IF produced various vital assets such as interoperability guidelines (latest v4.3, content protection, ATSC 3.0, SAND), test vectors, conformance tools, and a reference client. For informative aspects of MPEG-DASH such as the bitrate adaptation schemes the interested reader is referred to our survey. This survey gives an overview about existing techniques (see figure below) and also outlines future research. It is available for free for everyone (open access).

Finally, I mentioned a couple of scientific events in 2018 including QoMEX, MMSys (NOSSDAV, PV), ICME, ICIP, PCS, and MIPR. I have attended all of the them (except PCS), each showing advances in their respective field. These events are probably worth to attend also in 2019 but I will certainly blog about this early next year. However, I'd like to hear your opinion of what happened in 2018 and what we may expect in 2019...

MPEG news: a report from the 123rd meeting, Ljubljana, Slovenia

The original blog post can be found at the Bitmovin Techblog and has been modified/updated here to focus on and highlight research aspects. Additionally, this version of the blog post will be also posted at ACM SIGMM Records.

MPEG News Archive

The MPEG press release comprises the following topics:

• MPEG issues Call for Evidence on Compressed Representation of Neural Networks
• Network-Based Media Processing – MPEG evaluates responses to call for proposal and kicks off its technical work
• MPEG finalizes 1st edition of Technical Report on Architectures for Immersive Media
• MPEG releases software for MPEG-I visual activities
• MPEG enhances ISO Base Media File Format (ISOBMFF) with new features

MPEG issues Call for Evidence on Compressed Representation of Neural Networks

Artificial neural networks have been adopted for a broad range of tasks in multimedia analysis and processing, media coding, data analytics, translation and many other fields. Their recent success is based on the feasibility of processing much larger and complex neural networks (deep neural networks, DNNs) than in the past, and the availability of large-scale training data sets. As a consequence, trained neural networks contain a large number of parameters (weights), resulting in a quite large size (e.g., several hundred MBs). Many applications require the deployment of a particular trained network instance, potentially to a larger number of devices, which may have limitations in terms of processing power and memory (e.g., mobile devices or smart cameras). Any use case, in which a trained neural network (and its updates) needs to be deployed to a number of devices could thus benefit from a standard for the compressed representation of neural networks.

At its 123rd meeting, MPEG has issued a Call for Evidence (CfE) for compression technology for neural networks. The compression technology will be evaluated in terms of compression efficiency, runtime, and memory consumption and the impact on performance in three use cases: visual object classification, visual feature extraction (as used in MPEG Compact Descriptors for Visual Analysis) and filters for video coding. Responses to the CfE will be analyzed on the weekend prior to and during the 124th MPEG meeting in October 2018 (Macau, CN).

Research aspects: As this is about "compression" of structured data, research aspects will mainly focus around compression efficiency for both lossy and lossless scenarios. Additionally, communication aspects such as transmission of compressed artificial neural networks within lossy, large-scale environments including update mechanisms may become relevant in the (near) future. Furthermore, additional use cases should be communicated towards MPEG until the next meeting.

Network-Based Media Processing – MPEG evaluates responses to call for proposal and kicks off its technical work

Recent developments in multimedia have brought significant innovation and disruption to the way multimedia content is created and consumed. At its 123rd meeting, MPEG analyzed the technologies submitted by eight industry leaders as responses to the Call for Proposals (CfP) for Network-Based Media Processing (NBMP, MPEG-I Part 8). These technologies address advanced media processing use cases such as network stitching for virtual reality (VR) services, super-resolution for enhanced visual quality, transcoding by a mobile edge cloud, or viewport extraction for 360-degree video within the network environment. NBMP allows service providers and end users to describe media processing operations that are to be performed by the entities in the networks. NBMP will describe the composition of network-based media processing services out of a set of NBMP functions and makes these NBMP services accessible through Application Programming Interfaces (APIs).

NBMP will support the existing delivery methods such as streaming, file delivery, push-based progressive download, hybrid delivery, and multipath delivery within heterogeneous network environments. MPEG issued a Call for Proposal (CfP) seeking technologies that allow end-user devices, which are limited in processing capabilities and power consumption, to offload certain kinds of processing to the network.

After a formal evaluation of submissions, MPEG selected three technologies as starting points for the (i) workflow, (ii) metadata, and (iii) interfaces for static and dynamically acquired NBMP. A key conclusion of the evaluation was that NBMP can significantly improve the performance and efficiency of the cloud infrastructure and media processing services.

Research aspects: I reported about NBMP in my previous post and basically the same applies here. NBMP will be particularly interesting in the context of new networking approaches including, but not limited to, software-defined networking (SDN), information-centric networking (ICN), mobile edge computing (MEC), fog computing, and related aspects in the context of 5G.

MPEG finalizes 1st edition of Technical Report on Architectures for Immersive Media

At its 123nd meeting, MPEG finalized the first edition of its Technical Report (TR) on Architectures for Immersive Media. This report constitutes the first part of the MPEG-I standard for the coded representation of immersive media and introduces the eight MPEG-I parts currently under specification in MPEG. In particular, it addresses three Degrees of Freedom (3DoF; three rotational and un-limited movements around the X, Y and Z axes (respectively pitch, yaw and roll)), 3DoF+ (3DoF with additional limited translational movements (typically, head movements) along X, Y and Z axes), and 6DoF (3DoF with full translational movements along X, Y and Z axes) experiences but it mostly focuses on 3DoF. Future versions are expected to cover aspects beyond 3DoF. The report documents use cases and defines architectural views on elements that contribute to an overall immersive experience. Finally, the report also includes quality considerations for immersive services and introduces minimum requirements as well as objectives for a high-quality immersive media experience.

Research aspects: ISO/IEC technical reports are typically publicly available and provides informative descriptions of what the standard is about. In MPEG-I this technical report can be used as a guideline for possible architectures for immersive media. This first edition focuses on three Degrees of Freedom (3DoF; three rotational and un-limited movements around the X, Y and Z axes (respectively pitch, yaw and roll)) and outlines the other degrees of freedom currently foreseen in MPEG-I. It also highlights use cases and quality-related aspects that could be of interest for the research community.

MPEG releases software for MPEG-I visual activities

MPEG-I visual is an activity that addresses the specific requirements of immersive visual media for six degrees of freedom virtual walkthroughs with correct motion parallax within a bounded volume. MPEG-I visual covers application scenarios from 3DoF+ with slight body and head movements in a sitting position to 6DoF allowing some walking steps from a central position. At the 123nd MPEG meeting, an important progress has been achieved in software development. A new Reference View Synthesizer (RVS 2.0) has been released for 3DoF+, allowing to synthesize virtual viewpoints from an unlimited number of input views. RVS integrates code bases from Universite Libre de Bruxelles and Philips, who acted as software coordinator. A Weighted-to-Spherically-uniform PSNR (WS-PSNR) software utility, essential to 3DoF+ and 6DoF activities, has been developed by Zhejiang University. WS-PSNR is a full reference objective quality metric for all flavors of omnidirectional video. RVS and WS-PSNR are essential software tools for the upcoming Call for Proposals on 3DoF+ expected to be released at the 124th MPEG meeting in October 2018 (Macau, CN).

Research aspects: MPEG does not only produce text specifications but also reference software and conformance bitstreams, which are important assets for both research and development. Thus, it is very much appreciated to have a new Reference View Synthesizer (RVS 2.0) and Weighted-to-Spherically-uniform PSNR (WS-PSNR) software utility available which enables interoperability and reproducibility of R&D efforts/results in this area.

MPEG enhances ISO Base Media File Format (ISOBMFF) with new features

At the 123rd MPEG meeting, a couple of new amendments related to ISOBMFF has reached the first milestone. Amendment 2 to ISO/IEC 14496-12 6th edition will add the option to have relative addressing as an alternative to offset addressing, which in some environments and workflows can simplify the handling of files and will allow creation of derived visual tracks using items and samples in other tracks with some transformation, for example rotation. Another amendment reached its first milestone is the first amendment to ISO/IEC 23001-7 3rd edition. It will allow use of multiple keys to a single sample and scramble some parts of AVC or HEVC video bitstreams without breaking conformance to the existing decoders. That is, the bitstream will be decodable by existing decoders, but some parts of the video will be scrambled. It is expected that these amendments will reach the final milestone in Q3 2019.

Research aspects: The ISOBMFF reference software is now available on Github, which is a valuable service to the community and allows for active standard's participation even from outside of MPEG. It is recommended that interested parties have a look at it and consider contributing to this project.

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What else happened at #MPEG123?

• The MPEG-DASH 3rd edition is finally available as output document (N17813; only available to MPEG members) combining 2nd edition, four amendments, and 2 corrigenda. We expect final publication later this year or early next year.
• There is a new DASH amendment and corrigenda items in pipeline which should progress to final stages also some time next year. The status of MPEG-DASH (July 2018) can be seen below.

• MPEG received a rather interesting input document related to “streaming first” which resulted into a publicly available output document entitled “thoughts on adaptive delivery and access to immersive media”. The key idea here is to focus on streaming (first) rather than on file/encapsulation formats typically used for storage (and streaming second). This document should become available here.
• Since a couple of meetings, MPEG maintains a standardization roadmap highlighting recent/major MPEG standards and documenting the roadmap for the next five years. It definitely worth keeping this in mind when defining/updating your own roadmap.
• JVET/VVC issued Working Draft 2 of Versatile Video Coding (N17732 | JVET-K1001) and Test Model 2 of Versatile Video Coding (VTM 2) (N17733 | JVET-K1002). Please note that N-documents are MPEG internal but JVET-documents are publicly accessible here: http://phenix.it-sudparis.eu/jvet/. An interesting aspect is that VTM2/WD2 should have >20% rate reduction compared to HEVC, all with reasonable complexity and the next benchmark set (BMS) should have close to 30% rate reduction vs. HEVC. Further improvements expected from (a) improved merge, intra prediction, etc., (b) decoder-side estimation with low complexity, (c) multi-hypothesis prediction and OBMC, (d) diagonal and other geometric partitioning, (e) secondary transforms, (f) new approaches of loop filtering, reconstruction and prediction filtering (denoising, non-local, diffusion based, bilateral, etc.), (g) current picture referencing, palette, and (h) neural networks.
• In addition to VVC -- which is a joint activity with VCEG --, MPEG is working on two video-related exploration activities, namely (a) an enhanced quality profile of the AVC standard and (b) a low complexity enhancement video codec. Both topics will be further discussed within respective Ad-hoc Groups (AhGs) and further details are available here.
• Finally, MPEG established an Ad-hoc Group (AhG) dedicated to the long-term planning which is also looking into application areas/domains other than media coding/representation.

In this context it is probably worth mentioning the following DASH awards at recent conferences

• June 2018, DASH-IF awarded Excellence in DASH award at ACM MMSys 2018
• July 2018, DASH-IF awarded Grand Challenge on Dynamic Adaptive Streaming over HTTP at IEEE ICME 2018

Additionally, there have been two tutorials at ICME related to MPEG standards, which you may find interesting

• Trends and Recent Developments in Video Coding Standardization
• Delivering Traditional and Omnidirectional Media