Five Encoding Advancements Coming in AV1
In this posting, Bitmovin is covering five key tools included in AV1, which have been adopted to help reduce bandwidth demands by up to 30% while still retaining or improving picture quality.
Showing posts with label Codecs and Formats. Show all posts
Showing posts with label Codecs and Formats. Show all posts
Turing Codec: Open-Source HEVC Video Compression
BBC R&D has released the first version of the Turing codec, an open source software HEVC video encoder that allows highly efficient compression of video content with low computational complexity.
PrestoCentre Standards Register
The PrestoCentre Standards Register gathers information on standards for content and metadata used across all communities involved in audiovisual digital preservation.
Key Media Industry Organizations Launch Joint Task Force on File Formats and Media Interoperability
The launch of the Joint Task Force on File Formats and Media Interoperability was announced today by its sponsors, the North American Broadcasters Association (NABA), Advanced Media Workflow Association (AMWA), Society of Motion Picture and Television Engineers (SMPTE), International Association of Broadcast Manufacturers (IABM), American Association of Advertising Agencies (4A’s), and Association of National Advertisers (ANA). The European Broadcasting Union (EBU) is participating as an observer.
Bringing together manufacturers, broadcasters, advertisers, ad agencies, and industry organizations (standards bodies and trade associations) serving the professional media market, the Task Force has an ultimate goal to create greater efficiencies and cost savings for exchange of file-based content.
The group’s initial focus will be to gather and analyze requirements for a machine-generated and readable file interchange and delivery specification — including standardized and common structured metadata — for the professional media industry. Use case examples include promo, spot, and program delivery from a provider to a broadcaster.
In one of its initial actions, the task force has published a survey designed to collect data on user requirements. Open to any member of the media industry, the survey asks participants to create a one-sentence “user story” by identifying the nature of their work, the specific function they seek, and the business value that would be provided by that function.
Other task force activities will include the collection of data on existing products for transcode, transform, and file QC, and their ability to be driven by data from UML, XML, API, script, and other machine-to-machine communication mechanisms.
In addition to analyzing and publishing this data within a formal report, the task force will analyze the data in terms of current, planned, and unplanned standards activities and publish recommendations for future activities.
Source: SMPTE
Performance Comparison of HEVC, VP9, and H.264 Encoders
This work presents a performance comparison of the two latest video coding standards H.264/MPEG-AVC and H.265/MPEG-HEVC (High-Efficiency Video Coding) as well as the recently published proprietary video coding scheme VP9.
According to the experimental results, which were obtained for a whole test set of video sequences by using similar encoding configurations for all three examined representative encoders, H.265/MPEG-HEVC provides significant average bit-rate savings of 43.3% and 39.3% relative to VP9 and H.264/MPEG-AVC, respectively.
As a particular aspect of the conducted experiments, it turned out that the VP9 encoder produces an average bit-rate overhead of 8.4% at the same objective quality, when compared to an open H.264/MPEG-AVC encoder implementation – the x264 encoder. On the other hand, the typical encoding times of the VP9 encoder are more than 100 times higher than those measured for the x264 encoder.
When compared to the full-fledged H.265/MPEG-HEVC reference software encoder implementation, the VP9 encoding times are lower by a factor of 7.35, on average.
Telestream Announces Open-Source HEVC Encoder Project
Telestream has announced the public availability of an open source H.265 (HEVC) encoder. The new project aims to create the world’s most efficient, highest quality H.265 codec.
The iniative is being introduced under both an open source and commercial license model and is being managed by co-founder MulticoreWare Inc, Telestream’s development partner.
“Telestream and MulticoreWare have had great success in the acceleration and commercial deployment of x264 and believe that a similar approach with the collaborative development of the next generation of high-efficiency codecs will benefit the industry,” commented Shawn Carnahan, CTO at Telestream. “The x264 project proved the effectiveness of developing a codec of this complexity. Leveraging the x264 technology in this new project will ensure that the new codec is as robust, efficient and high quality as its predecessor.”
Jason Garrett-Glaser, lead developer of the x264 project added: "Previous collaboration between Telestream and MulticoreWare led to successful work on the GPU acceleration of x264, a task deemed by many to be incredibly difficult, if not impossible. With these accomplishments in mind, I am excited to support Telestream in the founding of the x265 project, which follows in the x264 tradition of high performance, quality, and flexibility under an open source license and business model."
Access is free under GNU LGPL licensing, and commercial licenses are available for companies wishing to use the resulting implementation in their products. More information can be found at x265.org, where companies and individuals can contribute to the project.
Source: TVBEurope
Google Adds its Free and Open-Source VP9 Video Codec to Latest Chrome Build
Google announced it has enabled its VP9 video codec by default on the Chrome dev channel. The addition means users of the company’s browser can expect to see the next-generation compression technology available out-of-the-box before the end of the year.
In May, Google revealed it was planning to finish defining VP9 on June 17, after which it would start using the technology in Chrome and on YouTube. On that day, the company enabled the free video compression standard by default in the latest Chromium build, and now it has arrived in the latest Chrome build.
VP9 is the successor to VP8, both of which fall under Google’s WebM project of freeing Web codecs from royalty constraints. Despite the fact that Google unveiled WebM three years ago at its I/O conference, VP8 is still rarely used when compared to H.264, today’s most popular video codec.
“A key goal of the WebM Project is to speed up the pace of video-compression innovation (i.e., to get better, faster), and the WebM team continues to work hard to achieve that goal,” Google says. “As always, WebM technology is 100% free, and open-sourced under a BSD-style license.”
For users, the main advantage of VP9 is that it’s 50 percent more efficient than H.264, meaning that you’ll use half the bandwidth on average when watching a video on the Internet. Yet that doesn’t take H.265 into account, the successor to H.264 that offers comparable video quality at half the number of bits per second and also requires its implementers to pay patent royalties.
Google today claimed VP9 “shows video quality that is slightly better than HEVC (H.265).” The company is of course biased, but we’re sure that comparisons by third-parties will start to surface soon.
In the meantime, Google says it is working on refining the VP9 toolset for developers and content creators as well as integrating it with the major encoding tools and consumer platforms. VP9 is already available in the open-source libvpx reference encoder and decoder, but Google still plans to optimize it for speed and performance, as well as roll out improved tools and documentation “over the coming months.”
VP9 is also meant to become part of WebRTC, an open project that lets users communicate in real-time via voice and video sans plugins, later this year. Google has previously said it wants to build VP9 into Chrome, and YouTube has also declared it would add support once the video codec lands in the browser.
The dev channel for Chrome is updated once or twice weekly. Since the feature has made it in there, it won’t be long before it shows up in the beta channel, and then eventually the stable channel.
By Emil Protalinski, The Next Web
Video Compression: More Bang with Fewer Bits
Video compression was one of the more ubiquitous topics at last month’s NAB Show. Perhaps equally ubiquitous was 4K and 8K. Seldom was one of either topic discussed without reference to the other.
Fortunately, in the world of digital television and digital video, a video-specific variation of Moore’s Law seems to be at work. With umpteen years of incremental NTSC picture quality progress that many viewers could barely see — if at all — the industry was ripe for the change to HDTV and self-contained big-screen displays.
Until Moore’s Law made it possible for common computers to handle digitized SD video, few analog engineers could envision what was in the future of the digital television. Some might remember the days of 1125/60 in the early 1990s. It was, more or less, the original analog HDTV format. Many design engineers were trying to compress it into the standard 6MHz broadcast television channel bandwidth using a variety of hardware-intensive systems. The industry even formed the 1125/60 Consortium before DTV was invented.
DTV, which was originally conceived to shoehorn HDTV into a standard 6MHz TV channel, has flooded the industry and viewing public with myriad unforeseen changes. Among many was progressive scan, streaming video, file-based video, the 1920 x 1080 raster and, more recently, 4K, 8K and beyond. While current DTV and ATSC transmission standards have capped the resolution TV stations can broadcast, computers, DVDs, the Internet and a host of video compression schemes and standards have eliminated barriers to delivering higher definition images to viewers from non-over-the-air sources. Current state-of-the-art video compression standards can reduce the bandwidth of baseband video by a factor of approximately 100.
The Codec
The first digital video codec standard was H.120. It was published in 1984 and revised in 1988, but the quality was so poor that there were very few users. H.120 was followed later in 1988 by H.261, an ITU-T video coding standard. The primary use for H.261 was for video transmission over ISDN lines at a resolution of 352 x 288 or 176 x 144.
MPEG-2, aka H.262, was first published in 1994. It paved the road to DTV, OTT and ATSC transmission, and it continues to be the standard used to create DVDs.
MPEG-4, aka H.264, was published in 2003 and is currently the most commonly used video codec and the standard for Blu-ray discs and HDTV.
Today, numerous compression standards are being used in a variety of ways to create and deliver content. The latest standards with the highest quality are JPEG 2000 (J2K) and more recently HEVC (High Efficiency Video Coding).
J2K
J2K is designed for compressing individual images, not video sequences. It is primarily used in production and video feeds with high bit rates up to approximately 120Mb/s. The higher bit rates make artifacts and blocking virtually invisible. It is hardware-intensive, and it can be accomplished in real time.
In J2K, each frame is compressed individually and, therefore, stands alone. In video compression terms, each individual complete frame is an I-Frame. While this feature is advantageous in maintaining video quality, its high bandwidth doesn’t lend itself well to distribution.
On April 15, 2013, the Video Services Forum issued a Technical Recommendation that defines profiles for streaming of JPEG 2000 Broadcast Profile in a MPEG-2 Transport Stream over IP with optional Forward Error Correction (FEC). The recommendation is for unidirectional transport of SD-SDI, HD-SDI and 3G-SDI signals, encapsulated in an RTP stream and transmitted via IP to a receiving device that will decode the output to an SDI signal.
HEVC
On the other hand, HEVC, aka H.265, and its modern predecessors H.264, MPEG-4, MPEG-2, Advanced Video Coding (AVC) use I-frames, P-frames and B-frames to encode moving images. To quickly review, the I in I-frame stands for Intra-coded and is a fully specified still image. The P in P-frame stands for Predicted picture, and it contains only the changes from the previous frame, saving unchanged data from having to be repeated. The B in B-frame stands for Bi-predictive. It saves more space than a P frame because it specifies the differences between it and the frame not just before it, but after it as well. Images are usually segmented into macroblocks, where prediction types can be determined based on the movement within each macroblock.
HEVC contains 33 directional modes for intra block prediction. MPEG-4 uses only eight directional modes. These modes use information from previously decoded neighboring prediction blocks. H.265 motion vector prediction is a 16-bit range for both H and V motion vectors (MVs) with quarter pixel precision. This gives HEVC a dynamic vector prediction range 16X greater than H.264.
Most pre-H.265 codecs independently encoded 16 x 16 pixel macroblocks. In HEVC, the image is split into Coding-Tree Units (CTUs), each up to 64 × 64 pixels. The root of a quadtree data structure. A Quadtree contains four branches that are used to partition a two-dimensional space which uses a recurring algorithm to subdivide it into four quadrants. The quadtree can then be sub-divided into leaf-level coding units (CUs), as illustrated in the following figure.
HEVC (H.265) represents the natural progression of Moore’s Law in video compression. In essence, the H.265 codec is twice as efficient as the H.264 codec. It increases the use of parallel processing, improves compressed video picture quality and supports higher resolutions such as 8K Ultra high definition television (UHDTV).
As early as 2004, the ITU-T Video Coding Experts Group began work toward a new video compression standard to take H.264 to the next level. The Group was considering two approaches. One was to create extensions to H.264. The other was to create a new standard.
Three years later, the ISO/IEC Moving Picture Experts Group (MPEG) began work on a similar project called High-performance Video Coding. Its goal was to achieve a 50-percent bit-rate reduction without affecting subjective picture quality. The works of both groups evolved into the HEVC joint project in 2010.
In February 2012, a Committee Draft of the HEVC standard was written. In July, an International Standard was drafted. In January 2013, the Final Draft International Standard was introduced. One month before the Committee Draft was completed, Qualcomm demonstrated an HEVC decoder operating on a dual-core 1.5GHz Android tablet at the Mobile World Congress. In August, Ericsson showed the SVP 5500, the world’s first HEVC encoder at IBC. From that point until the opening of last month’s NAB, approximately 20 manufacturers introduced new encoders. Several more new HEVC systems were introduced last month at the NAB Show.
HEVC is the Future
As of now, HEVC is simply a bit-stream structure and syntax standard but not an MPEG Transport Stream, although that is expected to happen in the next few months. It will take about a year for HEVC to be reduced to a silicon chip set. Some are predicting HEVC will be incorporated into some new set-top boxes (STBs) by 2014 or 2015. This will likely be the first opportunity for proud owners of new 4K TVs to receive 4K programming.
H.265 may also be the successor to H.264 for the next generation of 4K DVDs. A standard dual-layer Blu-ray disk contains up to 50GB of data, enough for typical feature-length movies. Typical feature-length movies encoded with HEVC in 4K will contain up to 100GB.
Some experts seem to agree that 4K with HEVC codec most likely won’t significantly penetrate the market until at least 2017. Given the universal population and long life cycle of STBs, the administration of the wholesale replacement of existing STBs is staggering.
A similar situation exists for the population of ATSC HDTV sets in the United States. With the apparent failure of 3-D TV to catch on, many are questioning the eagerness of the market to replace their existing HDTV display devices as they did with the shutdown of NTSC. Thus, the future of HEVC in broadcast transmission is unknown.
On the other hand, if it turns out 4K doesn’t catch on with consumers, HEVC can double the number of existing HDTV channels using the same amount of bandwidth. Either way, over-the-air broadcast adoption of HEVC is dependent on upcoming ATSC 3.0 specifications.
By Ned Soseman, Broadcast Engineering
Choosing JPEG 2000: The Growing Choice for Master File Format
Broadcasters, film studios and post-production houses are currently facing a major challenge in that the volume of generated video material is increasing dramatically. The result is a significant increase in the need for storage and archive capability.
Broadcasters and video archivists are also looking for long-term digital preservation. In most cases, the source material is not digital. Instead, it is on film that needs to be scanned or high-quality analog video tape.
A production and digital archive compression format, with no concessions in video content quality and the actual fabrication process, is the obvious choice — one that reduces storage costs compared to uncompressed video, while still maintaining indefinite protection from loss or damage. Such a format should preserve original quality, while also easily enabling the generation of most of the commonly used formats.
Several questions are frequent when selecting a format. What is the best physical long-term storage media for video content? What is a good candidate for a digital preservation? Can digital content be interpreted in the future? Various options are possible, and organizations have to decide carefully.
Today’s broadcasters understand the industry’s keywords: highest image quality, flexible delivery formats, interoperability and standardized profiles for optimal preservation. They also have a vested interest in a common high-end format to store, preserve and commercialize the avalanche of video footage generated globally. JPEG 2000 is the growing choice for master file format.
Digital Storage Keys
There are three keys to digital storage preservation:
- Ensure continuous access to content over time. Archive and storage covers all activities necessary to ensure continued access to digital materials for as long as necessary. This includes strategies to ensure access to reformatted and digitally-born content, regardless of the risks of media failure and technological changes. Quality preservation is crucial. A conversion system of archived items is important for dissemination or distribution.
- Everything that belongs together fits in one package. Archiving is an enduring process concerned with the impacts of changing technologies, whether it is the support of new media and data formats or a changing user community. “Long term” may extend indefinitely.
- Use open, well-documented industry standards — no proprietary formats. Ideally, focus on standards recognized and used for archiving applications. Open-file formats are published specifications, usually maintained by standards organizations, which can therefore be used and implemented by anyone. For example, an open format can be implemented by both proprietary and free/open-source softwares, using both types of software licenses. Open formats are also called free-file formats if they are not burdened by any copyrights, patents, trademarks or other restrictions. Anyone may use it at no cost for any desired purpose.
To standardize digital preservation practices and provide a set of recommendations for preservation program, the Reference Model for an Open Archival Information System (OAIS) was developed. OAIS is concerned with all technical aspects of a digital object’s life cycle: ingest into and storage in a preservation infrastructure, data management, accessibility and distribution. Continued interoperability is strategic; one needs easy and fast format conversion, as well as playback compatibility between manufacturers. For instance, a master file format must not be linked to any specific application, production format or major user.
JPEG 2000 in OP1a MXF
JPEG 2000 is based on Discrete Wavelet Transformation (DWT), scalar quantization, context modeling, arithmetic coding and post-compression rate allocation. JPEG 2000 provides random access (i.e., involving minimal decoding) to the block level in each sub-band, thus making it possible to decode a region, a low resolution or a low-quality image version without decoding the whole picture.
Functionally, JPEG 2000 is a true improvement that provides lossy and lossless compression, progressive and parseable code streams, error resilience, region of interest, proxies, random access and other features in one integrated algorithm.
In the video domain, JPEG 2000 is conceived as an intra-frame codec, so it closely matches the production workflow in which each video frame is treated as a single unit. Its ability to compress frame-by-frame has made it popular in the digital intermediate space in Hollywood. If the purpose of compression is the distribution of essence, and no further editing is expected, long-GOP MPEG will typically be preferred.
JPEG 2000 brings a storehouse of features to the broadcast process, whether ingest, transcoding, captioning, quality control or audio-track management is requested. Its inherent properties fully qualify it for high-quality, intermediate creation and masters archives. JPEG 2000 supports every resolution, color depth, number of components and frame rates; in short, the codec is future-proof.
The intra-frame quality of JPEG 2000 prevents error propagation over multiple frames and allows video signal edition at any given time. Two wavelet filters are included: the irreversible 9/7 and the fully reversible 5/3. The 5/3 wavelet filter offers a pure mathematically lossless compression, allowing an average 60-percent reduction in storage, while still allowing the exact original image information to be recovered. The 9/7 wavelet filter still performs visually lossless encoding. JPEG 2000 offers uncompressed quality, with no concession in video content quality and an important reduction in bandwidth and storage consumption.
Additionally, its scalability features a “create once, use many times” approach for a wide range of platforms. Easy transcoding of the codec appeals to high-end applications where workflows vastly benefit from transcoding to an intermediate version. JPEG 2000 ensures a clean, quick operation when bit-rate is at a premium.
Correctly transcoded HD1080p JPEG 2000 files compressed at 100Mb/s have been labeled “visually identical” to the 2K original footage by professional viewers. Furthermore, the wavelet-based JPEG 2000 compression does not interfere with the final — usually DCT-based — broadcast formats.
Post-production workflows consist of several encoding/decoding cycles. JPEG 2000 preserves the highest quality throughout this process, without any blocking artifacts creation. Moreover, all common bit depths, whether it is 8-bit, 10-bit, 12-bit or 16-bit, are supported.
Uniquely matching current industry needs, standardized broadcast profiles were adopted in 2010 (JPEG 2000 Part 1 Amd 3 – Profiles for Broadcast Application - ISO/IEC 15444-1:2004/Amd3), ensuring this wavelet-based codec its benchmark position in contribution, while fulfilling the industry-wide request for compression standards to archive and create mezzanine formats. A variety of media distribution channels can be transcoded.
The ongoing standardization process of the Interoperable Master Format (IMF) by SMPTE, focused on JPEG 2000 profiles, brings the adoption full-closure. The SMPTE standards also specify, in detail, how JPEG 2000 video data should be encapsulated in the widely adopted MXF.
Finally, a non-technical feature makes the JPEG 2000 open standard even more attractive for long-term projects; it is license- and royalty-free.
Other Codecs
Most other codecs are proprietary. Some have compliancy issues and several limitations to support any video formats or resolutions. The MPEG family is ideal for last-mile content delivery to viewers, but not for production and storage, since pictures have to be post-processed.
Conclusion
JPEG 2000 has gained significant attraction as a mezzanine format. Open and well-documented, the codec is future-proof and extendable. That said, it is not surprising that the Library of Congress, France’s Institut National de l’Audiovisuel and several Hollywood studios, such as 20th Century Fox, have selected the codec for storage and preservation.
JPEG 2000 is a codec like no others. It gives users a superior quality, control and a unique flexibility of the image processing chain. The growing use of JPEG 2000 to archive and create mezzanine files, and the ongoing standardization process of the IMF based on JPEG 2000, are just a few of its advantages.
By Jean-Baptiste Lorent, Broadcast Engineering
The Future of HEVC: It's Coming, but with Plenty of Questions
According to multiple studies, HEVC should deliver up to 50% better compression than H.264 in video on demand (VOD) applications, which means similar quality at half the bitrate. In live encoding, which obviously has to be performed in real time, the initial expectations are a 35% bandwidth reduction at similar quality levels. Alternatively, HEVC can also enable larger resolution movies, whether 2K or 4K.
Essentially, these are the two benefits of HEVC in the streaming space. The first relates to encoding existing SD and HD content with HEVC rather than H.264, enabling cost savings and/or the ability to stream higher quality video to lower bitrate connections. The second relates to opening up new markets for Ultra-High-Definition (UHD) videos.
On the playback side, there are multiple data points, but no real clear picture. Several companies have announced software decoders, but it’s unclear how much horsepower is necessary to drive them. The original targets for HEVC were 10x encoding complexity and 2x–3x decoding complexity as compared to H.264, and most sources have confirmed the 10x figure for encoding. Perusing various comments from various sources, decoding complexity has ranged from “same as H.264” to the 2x–3x figure.
Remember, however, that H.264 playback is accelerated in hardware on most playback platforms, including GPU-accelerated playback on computers. According to my source at graphics vendor NVIDIA, “There currently isn’t any dedicated [hardware] support for HEVC in our current GPUs. I’m pretty limited to what I can say about future products. But I’ll just say that our goal is for our GPUs to support all current video standards. Now, that said, it is quite possible for third parties to write HEVC encoders and decoders using CUDA to use the processing capability of current GPUs.”
Though GPU acceleration may be coming, it isn’t here yet, so H.264 and HEVC aren’t on a level playing field when it comes to accessible playback hardware. Still, according to a source at Qualcomm, Inc., “We are able to get 1080p, 30fps HEVC Main profile video with just a little bit over 50% CPU utilization on a quad-core architecture.”
On the mobile side, my source reported, “At CES we showcased Ittiam’s ARM based decoder and played back 1080p HEVC and 1080p H.264 videos side by side on recently announced Snapdragon 800 platform. Ittiam’s decoder is still in development and will get further enhancement.”
According to a report titled “HEVC Decoding in Consumer Devices,” senior analyst Michelle Abraham from Multimedia Research Group, Inc. estimated that the number of consumer devices that shipped in 2011 and 2012 that would be capable of HEVC playback with a software upgrade totaled around 1.4 billion, with more than a billion more expected to be sold in 2013. According to Abraham, in compiling these statistics she assumed that all PCs shipped in each year would be HEVC-capable.
HEVC Encoding
I spoke with several encoding companies; many were bullish on HEVC and have either made HEVC-related product announcements (Elemental Technologies, Inc.) or will at NAB. Another made the very cogent comment that the encoding side was always ahead of the game and that the path to actual producer adoption is widespread playback availability.
Speaking of playback, none of the major players -- Adobe, Apple, Google, or Microsoft -- have announced HEVC playback support in their respective players, browsers, or mobile or desktop operating systems. One reason why -- and a potential monkey wrench in at least the short-term HEVC adoption cycle -- is that no one knows what it will cost to use HEVC.
Royalty Issues with HEVC
What’s clear at this point is that multiple companies have patents relating to HEVC technology, and they plan to ask for royalties from those who use their technology. This was the case with H.264 as well, and though many in the streaming industry grumbled about the royalties, this disgruntlement certainly didn’t limit H.264’s success.
Two things are different with HEVC. First, where H.264 involved a single group of patent holders administered by MPEG LA, it appears that some HEVC patent holders want to pursue royalties outside of a patent group, which will make it more challenging for HEVC users to license the technologies. According to “Patent Snafus Could Delay New Video Codec,” Mediatek and Qualcomm do not want to join the HEVC group formulated by MPEG LA, and Samsung hasn’t decided either way.
One chipmaker executive, speaking anonymously for the EE Times article, commented, “HEVC has so many patent holders and some of them say they will not be part of the pool but want to collect royalties themselves. If say 20 people all want to collect royalties it will kill the standard -- we need a fixed cost, it cannot be variable,” he added.
Beyond this uncertainty, HEVC is coming to the streaming media market much faster than H.264, where royalty policies were in place well before any significant market adaption. To recount, the H.264 spec was approved in March 2003, and MPEG LA announced licensing terms in November 2003. Obviously, when Apple announced support for H.264 in QuickTime 7 in April 2005, royalty policies were firmly in place. Ditto for when Adobe announced that it would include H.264 in Flash in March 2008, and when Microsoft added H.264 to Silverlight in July 2009.
Our contact at MPEG LA reported that while the HEVC group had met three times as of February 2013, there was still no guarantee that a group would be formed or that all patent holders would join the group. So it appears that HEVC early adopters will have to decide to implement the technology without knowing the cost.
For large companies such as Adobe, Apple, Google, and Microsoft, that might be tenable; the H.264 license was capped, and it’s reasonable to assume that the HEVC license will also be capped. All four companies can amortize that cost over millions of product units shipped, and I think it’s highly likely that one or more of these companies will announce HEVC integration by NAB.
Even the encoding companies that I spoke with commented that they might incorporate HEVC technologies into their encoding tools without knowing the cost, because, as one exec said, “Supporting new formats is the race that we run.” The exec also noted, however, that this was the first time that they were ever forced to consider embracing a codec without having an idea about the licensing structure.
However, let’s get back to the two potential benefits that actual publishers seek from HEVC: cost savings and opening up new products and services. In both cases, it seems unlikely that any producer would use HEVC-encoded video without a known cost structure. Sure, H.264 usage for free internet video is free, but that decision was made under a completely different set of circumstances, and it’s doubtful if HEVC usage will be similarly unencumbered.
How H.264 Became Free
A short history lesson will explain why H.264 became free. When the terms of the initial H.264 license were announced, there was a royalty on H.264-encoded video deployed in a pay-per-view or subscription operation. The royalty was not on free internet video, at least through the initial term of the license, which ended Dec. 31, 2010.
The licensing terms attributed this waiver to the fact that the internet streaming market was “still developing,” though this is likely disingenuous. The fact of the matter was that the H.264 implementations of that time offered only a slight quality improvement over VP6, the predominant Flash codec, and required more CPU horsepower for playback. There was also no mobile platform such as iOS or Android that wasn’t compatible with VP6 that could force producers to use H.264. So 99% of producers were satisfied with VP6 and wouldn’t have experimented with H.264 if there was a royalty involved.
In February 2010, MPEG LA extended the royalty moratorium for free internet video through December 2016. In an interview with Streaming Media, MPEG LA president and CEO Larry Horn attributed this decision to the fact that “though some companies are doing well with advertising supported video, overall the models are still in flux, and the patent group didn’t want to plug a royalty into a business model that’s still unsettled.”
In May 2010, Google announced WebM, an open source alternative to H.264 that offered very similar quality and playback performance. In August 2010, MPEG LA announced that there would be no royalties on free internet usage of H.264 in perpetuity. Though MPEG LA never publicly admitted that the availability of a free, open source solution contributed to this decision, the timing would suggest it did.
Why HEVC Probably Won’t Be Free
Fast-forward to 2013. HEVC is ready, and at this point, it has no real competition. Sure, you can point to VP9, but considering how poorly Google executed taking VP8/WebM to market, it’s unlikely that any producers -- or patent groups -- will take it seriously. In 2012, online video advertising jumped to $2.9 billion, so it’s tough to say that this market is still in flux.
For these reasons, it seems unlikely that if HEVC enables large publishers to cut their bandwidth costs by 50%, HEVC patent holders wouldn’t want their share. It seems equally unlikely that publishers seeking to reduce bandwidth costs via HEVC would start using the technology until the cost structure was known. So HEVC implementation seeking to harvest this benefit is likely on hold pending the announcement.
HEVC and UHD Video
Again, I’m focusing my analysis on the streaming and OTT markets, since those are the ones I know best. Even without considering the royalty cost uncertainties, it seems unlikely that HEVC will spawn many new UHD-related products and services over the next 2 or 3 years for three reasons: bandwidth, the lack of 4K displays, and the lack of content.
Let’s start with bandwidth. In his blog post “H.265/HEVC Ratification and 4K Video Streaming,” compressionist Alex Zambelli, previously with Microsoft and now with iStreamPlanet, estimated that if HEVC produced a 40% bandwidth saving over H.264, a 4K movie would require bitrates of between 12Mbps and 15Mbps. Assuming that HEVC actually produced the 50% target, these numbers would drop to 10Mbps and 12Mbps.
According to the latest Akamai Technologies “State of the Internet” report, for 3Q 2012, the average connection speed in the U.S. was about 7.2Mbps, up from about 6Mbps the previous year. While users connecting on some premium services could handle HEVC’s 10Mbps–12Mbps in the short term, it’s unclear when a significant portion of the U.S. population will be able to support 4K HEVC movies.
Though the U.S. is far from the performance leader, only South Korea, with an average connection speed of 14.7Mbps, could sustain a 4K movie today, with Japan next at 10.5Mbps. Again, while dedicated satellite or cable networks could certainly carry this load, it’s unlikely that the type of shared internet connection used for OTT would be able to in the short term.
‘Why 4K TVs Are Stupid’
The second issue relates to the installed base of 4K-capable sets, which obviously will be necessary to view 4K movies. According to analyst DisplaySearch, global shipments of 4K sets will be well under a million in 2013, and just over 2 million in 2014.
Obviously, these are not inspiring numbers, and as you might have gleaned from the section title, there are those who feel they may be overly optimistic. In a CNET article titled “Why 4K TVs Are Stupid,” Geoffrey Morrison ran the math about how much detail your eyes can resolve, and the minimum size of pixels on a screen, and concluded that at a viewing distance of 10', the difference between 1080p and 4K wouldn’t be noticeable on TVs less than 77" in diagonal. It’s a pretty familiar argument, very similar to the 720p versus 1080p debate, where the rule of thumb was that you couldn’t tell the difference on TVs 50" or smaller when watching from farther than 8' away.
In other words, while 4K TVs might make sense for a home entertainment center or man cave, they probably don’t for the typical living room, where mass markets are made. At some point, economies of scale will take over, and 4K sets will be cheaper than 1080p. Until that happens, however, it’s hard to predict that 4K sets will fly off the shelves, particularly because of the third item that will hinder 4K sets, and services targeting them -- a paucity of content.
No Content for 4K
By the time 1080p TV sets became affordable for the masses, there was plenty of HD content to watch. While ultimately we may say the same thing about 4K TVs, that time is clearly not now, both regarding affordability and content.
A good example of both is the 84" Sony XBR-84X900, which retails for $24,999.99 and includes 10 4K movies from Sony’s movie library and a variety of short-form 4K content. To supplement these movies, Sony plans on launching a 4K movie download service in the summer of 2013, potentially delivered on a new Blu-ray Disc standard for 4K movies.
Many movies today are being shot in 4K, and many film-based movies can be rescanned for 4K delivery. Beyond this, however, there’s very little other 4K content available, and minimal 4K production in sports and general-purpose television. So even those viewers who purchase a sufficiently large 4K monitor so that they can see the advantage over 1080p will have little 4K content to watch.
Of course, many 4K TVs can upsample SD and HD content to 4K, with mixed results. One U.K. reviewer found the results “astonishingly good,” while another, more expressive reviewer from Gizmodo commented, “As a result, anyone who spends £20,000 on a 4K TV at the moment will be doomed to watch upscaled HD content. That sucks. You don’t spend quite-nice-car cash on a TV, just so you can watch upscaled content.”
Note that some of the less expensive 4K TVs, such as Westinghouse Electric Corp.’s $2,499 50" set, don’t come with onboard Smart TV functionality or 4K upscaling technology. In these cases, you’d be dependent upon the upscaling provided by the set-top box, optical disc player, or game console.
What does all of this mean for the UHD OTT market? Overall, even though it seems likely that inexpensive HEVC-capable set-top boxes will be available by the end of 2013, there will be minimal 4K content to watch, few 4K TVs to watch it on, and insufficient bandwidth to deliver it.
Download and Watch
One market that seems potentially ripe for larger-than-1080p viewing is the traditional download to view, particularly given the multiple viewing options. For example, TimeScapes is a film by Tom Lowe featuring slow-motion and time-lapse cinematography of the landscape, people, and wildlife of the American Southwest. Shot in 4K, the movie is available in 10 versions, ranging from SD DVD and 1080p Blu-ray to 4K, including custom versions for 30" 2560x1440 displays and the MacBook Retina display (2880x1620). It’s an innovative strategy that could portend the optimal strategy for UHD movie distribution.
I asked Lowe about how his sales were distributed among the available offerings. He responded, “Actually the ‘30 inch’ 2560x1440 version is selling like hotcakes. Sales have exceeded my expectations, in terms of percentage sold vs Blu-ray, 1080p download, etc. I would say for every one in ten 1080p HD downloads we sell, we sell about four 2560 copies. So many people have the Dell and Apple 2560 displays, but have never, ever had any video to play at that resolution.”
Interestingly, watching video on tablets and computers seems like the optimal use of 4K screens, as viewers are actually close enough to the device to see the difference. Though it will likely never see the light of day, Panasonic showed an 18.7 x 13.1 tablet computer at CES with a 4K screen -- could true 4K tablets be far behind? And once they’re available, wouldn’t 4K movie downloads from iTunes seem like the natural next step? Once HEVC playback becomes available, it would cut download times and storage space by 50%.
How likely is true 4K viewing on computers? I asked Lowe for his thoughts about computers and tablets as a potential viewing platform. He replied, “I have always believed that 4K monitors are where 4K will really catch on. On a projector, or large TV, you don’t notice it as much. On a monitor only a couple feet away, the difference between 1080p and 4K is very striking. I think 4K monitors will catch on fast once they come out, among gamers, Photoshop enthusiasts, and people watching or making high-res video.”
Conclusions
What’s this add up to? For producers seeking to distribute SD and HD content encoded with HEVC, the lack of a known royalty structure is a major buzzkill. At this point, no one knows whether a single royalty structure will be in place or whether multiple IP properties will pursue royalties independently, or the timing of either of these efforts.
HEVC encoding should be generally available by the end of 2013, if not sooner, and the player-related picture should also be clearer. Though it’s impossible to predict what Apple will do, I would be surprised if there wasn’t an HEVC decoder for the iPad 3 and MacBook Retina line announced before the end of 2013. Ditto for Adobe announcing HEVC playback in Flash.
Those attempting to leverage HEVC to create new opportunities for the distribution of UHD video have the royalty mountain to climb, as well as a paucity of content and viewing platforms and the lack of bandwidth to deliver the streams. Given the data rates involved, it feels like downloading for viewing is a better short-term model, providing custom resolutions for specific resolution displays.
The increased efficiency that HEVC provides will ultimately make streaming video more affordable and deliverable. However, until the royalty picture clears, it’s hard to get excited about any projected cost savings from HEVC. On the UHD side, HEVC is only one piece of the puzzle that must come together to make 4K viewing a reality, and not a very important piece of the puzzle at that.
By Jan Ozer, StreamingMedia
WTF is... H.265 aka HEVC?
When Samsung unveiled its next-generation smartphone, the Galaxy S4, in March this year, most of the Korean giant’s fans focused their attention on the device’s big 5-inch, 1920 x 1080 screen, its quad-core processor and its 13Mp camera. All impressive of course, but incremental steps in the ongoing evolution of the smartphone. More cutting edge is the S4’s promised support for a technology called HEVC.
HEVC is short for High Efficiency Video Coding. It’s the successor to the technology used to encode video stored on Blu-ray Discs and streamed in high-definition digital TV transmissions the world over. The current standard is called H.264 - aka MPEG 4, aka Advanced Video Coding (AVC) - so it’s no surprise that HEVC will become H.265 when the Is and Ts are dotted and crossed on the final, ratified version of the standard later this year.
This final standardisation is just a formality. The International Telecommunication Union (ITU-T), the body which oversees the "H" series of standards, and its partner in video matters, the ISO/IEC Moving Picture Experts Group (MPEG), have both given HEVC sufficient approval. This means device manufacturers such as Samsung, chipmakers such as Broadcom, content providers such as Orange France and mobile phone network operators such as NTT DoCoMo can begin announcing HEVC-related products safe in the knowledge that the standard will be completed with few, if any further changes.
It has taken H.265 three years to reach this stage, though exploratory work on post-H.264 standards goes back to 2004. The drive to develop the standard - a process overseen by a committee called the Joint Collaborative Team on Video Coding (JVT-VC) and comprising members of both MPEG and ITU-T - was outlined in January 2010 in a call for specification proposals from technology firms and other stakeholders.
Their brief is easy to summarise: H.265 has to deliver a picture of the same perceived visual quality as H.264 but using only half the transmitted volume of data and therefore half the bandwidth. H.264 can happily churn out 1920 x 1080 imagery at 30 frames per second in progressive - ie, frame after frame - mode, but it’s expected to start running out of puff when it comes to the 3840 x 2160 - aka 4K x 2K - let alone the 7680 x 4320 (8K x 4K) resolutions defined as Ultra HD pictures. H.265, then, was conceived as the technology that will make these resolutions achievable with mainstream consumer electronics kit like phones and televisions.
High Resolution, Low Bandwidth
Of course, 4K x 2K and up are, for now, thought of as big-screen TV resolutions. But it wasn’t so very long ago that 1920 x 1080 was considered an only-for-tellies resolution too. Now, though, plenty of phones, of which the Galaxy S4 is merely the latest, have screens with those pixel dimensions. Some tablets have higher resolutions still.
And while today’s mobile graphics cores have no trouble wrangling 2,073,600 pixels 30 times a second, that’s still a heck of a lot of data for mobile networks to carry to them, even over the fastest 4G LTE links. And so, in addition to supporting Ultra HD resolutions on large TVs, H.265 was conceived as a way to deliver larger moving pictures to phones while consuming less bandwidth requirements than H.264 takes up. Or to deliver higher, smoother frame rates over the same width of pipe.
This explains NTT DoCoMo’s interest in the new video technology. Its 2010 proposal to the JVT-VC was one of the five shortlisted from the original 27 suggestions in April 2010. All five could deliver a picture to match a good H.264 stream, but only four, including NTT DoCoMo’s, were also able to deliver a compression ratio as low as a third of what H.264 can manage. The JVT-VC’s target was 50 per cent more efficient compression for the same image size and picture quality.
The remaining proposals were combined and enshrined the the JVT-VC’s first working draft, which was published the following October. The committee and its partners have been refining and testing that specification ever since. Since June 2012, MPEG LA, the company that licences MPEG video technologies, has been bringing together patent holders with intellectual property that touches on the H.265 spec, before licensing that IP to anyone making H.265 encoders and decoders, whether in hardware or software.
So how does the new video standard work its magic?
Like H.264 before it - and all video standards from H.261 on, for that matter - HEVC is based on the same notion of spotting motion-induced differences between frames, and finding near-identical areas within a single frame. These similarities are subtracted from subsequent frames and whatever is left in each partial frame is mathematically transformed to reduce the amount of data needed to store each frame.
Singing, Ringing Tree
When an H.264 frame is encoded, it’s divided into a grid of squares, known as "macroblocks" in the jargon. H.264 macroblocks were no bigger than 16 x 16 pixels, but that’s arguably too small a size for HD imagery and certainly for Ultra HD pictures, so H.265 allows block sizes to be set at up to 64 x 64 pixels, the better to detect finer differences between two given blocks.
In fact, the process is a little more complex than that suggests. While H.264 works at the block level, with a 16 x 16 block containing each pixel’s brightness - "luma" in the jargon - and two 8 x 8 blocks of colour - "chroma" data - H.265 uses a structure called a "Coding Tree". Encoder-selected 16 x 16, 32 x 32 or 64 x 64 blocks contain pixel brightness information. These luma blocks can then be partitioned into any number of smaller sub-blocks containing the colour - "chroma" - data. More light-level data is encoded than colour data because the human eye is better able to detect differences the brightness of adjacent pixels than it is colour differences.
HEVC samples pixels as "YCrCb" data: a brightness value (Y) followed by a number that shows how far the colour of the pixel deviates from grey toward, respectively, red and blue. It uses 4:2:0 sampling - each colour sample has one-fourth the number of samples than brightness and specifically half the number of samples in each axis. Samples are 8-bit or 10-bit values, depending on the HEVC Profile the encoder is following. You can think of a 1080p picture containing 1920 x 1080 pixels worth of brightness information but only 960 x 540 pixels worth of colour information. Don’t worry about the "loss" of colour resolution - you literally can’t see it.
A given "Coding Tree Unit" is the root of a tree structure that can comprise a number of smaller, rectangular "Coding Blocks", which can, in turn, be dividing into smaller still "Transform Blocks", as the encoder sees fit.
The block structure may differ between H.264 and H.265, but the motion detection principle is broadly the same. The first frame’s blocks are analysed to find those that are very similar to each other - areas of equally blue sky, say. Subsequent frames in a sequence are not only checked for these intrapicture similarities but also to determine how blocks move between frames in a sequence. So a block of pixels that contain the same colour and brightness values through a sequence of frames, but changes location from frame to frame, only needs to be stored once. An accompanying motion vector tells the decoder where to place those identical pixels in each successive recovered frame.
Made for Parallel Processing
H.264 encoders check intrapicture similarities in eight possible directions from the source block. H.265 extends this to 33 possible vectors - the better to reveal more subtle pixel block movement. There are also other tricks that H.265 gains to predict more accurately where to duplicate a given block to generate the final frame.
As HEVC boffins Gary Sullivan, Jens-Rainer Ohm, Woo-Jin Han and Thomas Wiegand put it in a paper published in the IEEE journal Transactions on Circuits and Systems for Video Technology in December 2012: “The residual signal of the intra- or interpicture prediction, which is the difference between the original block and its prediction, is transformed by a linear spatial transform. The transform coefficients are then scaled, quantised, entropy coded and transmitted together with the prediction information.”
When the frame is decoded, extra filters are applied to smooth out artefacts generated by the blocking and quantisation processes. Incidentally, we can talk about frames here, rather than interlaced fields, because H.265 doesn’t support interlacing. So there will be no 1080i vs 1080p debate with HEVC. “No explicit coding features are present in the HEVC design to support the use of interlaced scanning,” say the minds behind the standard. The reason? “Interlaced scanning is no longer used for displays and is becoming substantially less common for distribution.” At last we’ll be able to leave our CRT heritage behind.
In addition to all this video coding jiggery pokery, H.265 includes the kind of high-level information that H.264 data can contain to help the decoder cope with the different methods by which a stream of video data can move from source file to screen - along a cable or across a wireless network, say - which will result in degrees of data packet loss. But HEVC gains extra methods for segmenting an image or the streamed data to take better advantage of parallel processing architectures and synchronise the output of however many image processors are present.
H.264 has the notion of "slices" - sections of the data that can be decoded independently of other sections, either whole frames or parts of frames. H.265 adds "tiles", which are an even number of 256 x 64 slices into which a picture can be optionally segmented so that each contains the same number of HEVC’s core Coding Tree Units so there’s no need to synchronise output. This is because each graphics core processes any given CTU in the same amount of time. Other tiles sizes may be allowed in future versions of the standard.
H.265... Everywhere
An alternative option available to the encoder is Wavefront Parallel Processing, which cuts each slice into rows of CTUs. Work can begin on processing any given row once just two CTUs have been decoded from the preceding row (once decoding clues have been recovered from them). The exception, of course, is the very first row in the sequence. This approach, say HEVC boffins, makes for fewer artefacts than tiling and may yield a higher compression ratio, but its processing power requirements are greater than tiling. For now, the choice is tiles, WPP or neither, though the use of both may be permitted in future HEVC revisions.
H.265 makes jumping around within the video a smoother process by allowing complete frames - pictures that can be decoded without information from any preceding frame - to be more logically marked as such for the decoder. Don’t forget, the decoding order of information within a stream isn’t necessarily the same as the order in which the frames are displayed. Jump into a stream part-way and some upcoming complete frames that are needed for decode pre-entry point frames but not for those that will now be displayed can - if correctly labelled - be safely ignored by the decoder.
Since a video stream of necessity must incorporate at least one complete frame, it’s no surprise that H.265 has a still-image profile, Main Still Picture. Like the basic, Main profile, MSP is capped at eight bits per sample. If you want more, you’ll be needing the Main 10 profile, which, as its name suggests, used 10-bit samples. So far 13 HEVC levels have been defined, essentially based on the picture size and running from 176 x 144 to 7680 x 4320. The levels yield maximum bitrates of 128Kbps to 240Mbps in the mainstream applications tier, and 30-800Mbps in the high performance tier, which might be used for broadcast quality pre-production work and storage, for instance.
This, then, is the version of HEVC enshrined on the first final drafts of H.265. Work is already underway on extensions to the specification to equip the standard with the technology needed for 3D and multi-view coding, to support greater colour depths (12-bit initially) and better colour component sampling options such as 4:2:2 and 4:4:4, and to enable scalable coding, which allows a high quality stream to deliver a lower quality sub-stream by dropping packets.
The H.265 extensions are all some way off. First we all need H.265 to be supported by our preferred operating systems, applications and - in the case of low-power mobile devices - in the chips they use. With H.264 now the de facto standard for video downloads and streaming, there’s a motivation to move up to the next version, especially if it means buyers can download comparable quality videos in half the time. It seems certain to be a part of "Blu-ray 2.0" whenever that emerges, and probably future ATSC TV standards, but the ability to get high quality video down off the internet is surely a stronger unique selling point than delivering 4K or 8K video on optical disc to an ever-declining number of consumers.
Not Yet Ready for Primetime
Videophiles will demand 4K and perhaps 8K screens, but for most of us there’s little visible benefit in moving beyond 1080p - unless we also move our sofas very much closer to our TVs. Even if broadcasters migrate quickly to 4K, perhaps in time to show 2014’s World Cup tournament in the format, they can do so with H.264. But if you’re going to have to get a new, bigger screen, you may as well get one with a new, better codec on board. Still, H.265 in the living room looks set to be of limited interest for some years yet.
4K streaming may be equally far off, but more efficient 1080p streaming is something many folks would like to have now. Given the competition among IPTV services, it’s not hard to imaging many providers hopping upon H.265 to improve their offerings, once the standard becomes supported by the web browsers and apps they use. Greater compression of SD and HD video content than H.264 can provide is what will drive adoption of H.265 in the near-term.
And of course, it’s going to require greater processing power than previous codecs needed - 10 times as much for encoding, some specialists reckon, with two-to-three times as much for decoding. Producing H.265 video requires the encoder to evaluate many more encoding options at many more decision points that is the case with H.264, and that takes time. Likewise regenerating complete frames from the many more hints that the encoder provides. Encoding and decoding HEVC doesn’t necessarily favour chips with higher clock speeds, though. H.265’s emphasis on parallelisation favours CPUs and GPUs equipped with lots of cores that can crunch numbers simultaneously.
“HEVC/H.265 is an ideal fit for GPU encoding,” say staffers at Elemental Technologies, a maker of video encoding hardware. “HEVC/H.265 encoding presents computational complexities up to ten times that of H.264 encoding, for which the massively parallel GPU architecture is well-suited. With 500 different ways to encode each macroblock, the demanding processing requirements of H.265 will strain many existing hardware platforms.”
Easy to say, harder to deal with. We won’t know how well encoders and decoders work - be they implemented in software or hardware - until they actually arrive. Software support will come first. Market-watcher Multimedia Research Group reckons there are around 1.4 billion gadgets already on the market that, given a suitable software upgrade, will be able to play H.265 video. A billion more are coming out this year. But being able to decode H.265 is one thing - being able to do so smoothly and with an efficient use of energy is something else.
This kind of uncertainty will hold H.265 back in the short term, at least as far as its mainstream adoption goes. That’s no great surprise, perhaps. Even today, the majority of Britain’s broadcast digital TV channels used MPEG-2 - aka H.262 - with H.264 used only for HD content. H.265-specific chippery is expected this year, but not in shipping product until Q4 at the earliest - Q1 2014 is a more practical estimate.
By Tony Smith, The Register
Browse Proxy Transcoder
The use of a browse file – a frame accurate low bit rate proxy of the master essence – is an important enabler in lightweight IT based broadcast and production workflows.
The BLM Ingest service provides the ability to create the browse proxy in real time during linear ingest and in BLM deployments in which material arrives in the file domain a simple browse proxy transcoder is provided for ‘low-res’ generation.
BLM now make this simple tool available in a cut-down watch-folder only version to allow system builders to reap the benefit of low-res operations without having to tie up a fully featured transcoder.
The service will accept source material as an D-10 IMX, DNxHD, AVCi-100, DVCPro, XDCAM HD, MPEG-2, DV, H.264 or ProRes and transcode it to a defined resolution and bit rate.
Professional Transcoding with Consistent Color
5DtoRGB is an awesome tool that extracts every last drop of video quality from cameras that record to the AVC/H.264 video format. Cameras like the Canon EOS series of HDSLRs record video in this format with subsampled color.
Because of this compression, the picture is at risk of massive quality loss during the post production pipeline. By using a very high quality conversion process, 5DtoRGB gets you as close as possible to the original data off the camera's sensor while putting the brakes on any additional quality loss.
5DtoRGB is designed to transcode your footage to a format suitable for editing or visual effects purposes. Transcoding to formats like Apple ProRes or Avid DNxHD offer performance improvements during editing and keep compatibility with other editing systems in a collaborative environment.
Uncompressed formats like DPX are useful for visual effects creation (like pulling mattes from green screen footage), as uncompressed files retain the most image quality. Furthermore, visual effects compositing programs like After Effects or Nuke work with RGB color (not YCbCr, which is common in HDSLRs), and so a YCbCr to RGB conversion must be performed by either QuickTime or your compositing program before anything useful can be done.
The big problem is that you have to trust your NLE or compositing app to do a good job of performing this YCbCr to RGB conversion. Many programs use QuickTime internally to decode H.264 and perform the necessary YCbCr to RGB conversion, but its decoder is intended for general purpose use and not critical post-production use.
While this may be just fine for general activities like watching videos, it is unsuitable for professional post-production tasks. To add insult to injury, QuickTime adds noise to its H.264 output (and so does any program that uses QuickTime to decompress H.264) in what appears to be an attempt to cover up H.264 compression artifacts. And guess what? There's no way to disable this. You're stuck with it if you've converted your footage with Final Cut Pro, Compressor, MPEG Streamclip or Canon's E1 "Log and Transfer" plugin for Final Cut Pro. Each one of them uses QuickTime to decompress H.264. For an example of the results, click here.
5DtoRGB takes a no-compromise approach to quality. 5DtoRGB bypasses QuickTime decoding altogether, works internally at 10 bits and uses your video card's GPU for its YCbCr to RGB conversion. It also recognizes Canon's full range 8 bit YCbCr values (0-255), avoiding clipping and the resulting loss of picture information. The resulting files are the absolute highest quality you'll ever get out of the camera. In fact, you could argue that they're even better than the camera originals since they've undergone high quality chroma smoothing.
5DtoRGB supports both embedded timecode (used by the Canon 60D) and timecode stored in THM files. Start timecode values are derived from these sources, just like with Canon's official E1 plugin for Final Cut Pro and inserted into the DPX files or ProRes QuickTime files. You can also specify your own timecode value if you want.
5DtoRGB runs right now on Mac OS X and Windows. Linux users can run the Windows version using Wine.
Mobility and OTT will Drive Early H.265 Adoption
Ratification of the H.265 (High Efficiency Video Coding) standard by the ITU (International Telecommunications Union) late January clears the way for its adoption as the anointed successor to H.264/MPEG4.
Henceforth to be known as H.265, the questions now are how quickly will it ripple through the market, and when we will arrive at an all H.265 world?
The answer is that H.265 will have a quite different adoption profile from H.264, being slower to be taken up by makers of traditional managed set top boxes, but much quicker for consumer devices.
When H.264 was at a similar stage a decade ago after its ratification in June 2003, there were in any case hardly any consumer devices for consumption of video content other than TVs and DVD players. This is the first big difference today, the existence of smartphones and tablets with a frenetic pace of product innovation and release that has vendors such as Apple eating their own lunch every six months or so. They will be the early adopters of H.265, which will be standard in tablets and smartphones by the end of 2014 if not a bit sooner.
By contrast, we will then be seeing only the first adoption of H.265 by the set tops based on chips that were announced by Broadcom at last month’s Consumer Electronics Show (CES) in Las Vegas.
The eagerness by the CE makers to adopt H.265 is driven by two markets, mobility and fixed line OTT, although with a different flavor in each case. For mobility bandwidth reduction is the primary driver as proliferating video threatens to bring cellular infrastructures to their knees. This will remain the case even though Cisco has just revised downwards its forecasts for mobile data volumes up till 2017 from the giddy numbers that had been projected.
So, although mobile data can and increasingly will be offloaded via WiFi onto broadband networks, even there the ability of H.265 to halve the bandwidth compared with H.264 will yield big cost savings. Over time, deployment of H.265 will also allow video quality to improve over mobile networks, but the emphasis in the short term at least will be on bandwidth reduction for video at existing resolutions.
In the case of fixed line OTT, it is the either way around, with quality in the driving seat. There, H.265 is seen as a way of delivering HD services over limited bandwidth, and I can see little reason why operators will not seize the opportunity. There is also an interesting IPTV angle, where the motive could be to increase the range rather than the quality, extending the existing service to consumers previously too far from the nearest exchange to obtain adequate QoS.
By halving the bandwidth required for a given quality it may be possible almost to double the distance. Even for those operators that currently deliver IPTV exclusively over Fiber to the Home, enabling multichannel HD services, H.265 may open up the possibility of reaching more customers via VDSL2 over copper, at distances up to 1 Km from the nearest fiber end point.
The other main driver for H.265 is ultra HD or 4K, and here, things get interesting. I have to admit to being among those who saw H.265 as inadequate for 4K transmission, given that it will generate 8X as many bits per second as most current 720p or 1080i HD services. But, that was before I looked more closely at the specification.
Although H.265 is touted as being about twice the efficiency of H.264, it will do far better than that for 4K. The reason is simply that at those high resolutions there will be even more scope for intra frame compression, because any area of the picture that is all a similar color can be represented in virtually the same number of bits irrespective of the pixel density.
For example, in the case of a sporting event where there is a lot of grass in the picture, that region can effectively be encoded with the same number of bits within ultra HD as standard definition, which means that the bit-rate reduction is correspondingly greater for the former. H.265 has been designed with this in mind through its support for larger blocks of pixels up to 64 x 64 than the 8x8 typically used in current H.264 codecs.
H.265 will also be able to exploit parallel processing, which will be employed in future codecs, by dividing the picture in the first instance into tiles that can be encoded independently of each other, giving further potential for efficient compression of ultra HD. For this reason I think that current estimates that H.265 will enable delivery over the Internet at bit rates between 20 Mbps and 30 Mbps, as against 45 Mbps for H.264, are too conservative. It looks now that H.265 could achieve a three or even fourfold improvement over H.264 for ultra HD, which means that 15 Mbps should certainly be achievable.
Even so, we are not going to be seeing widespread 4K services anytime soon, remembering also that it only really scores for TVs bigger than 50 inches and even then only given the right viewing distance. Although there is still debate over the relationship between screen size, distance and the resolution beyond which there is no discernible improvement in quality, it is clear that for several years ultra HD will be a niche market driven by the same cutting edge operators that currently offer 1080p60 HD.
It also looks unlikely there will be the same wholesale stampede to H.265 among set-top box makers that there was to H.264 But, in the case of tablets and smartphones, the stampede will be all the more notable.
By Philip Hunter, Broadcast Engineering Blog
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