Transition from SD to HD on television: the definitive guide

Jorge Pérez López, broadcast commercial in Data Average, addresses in depth the keys that will allow televisions to complete their transition to HD before January 1, 2023, the deadline to make the leap in Spain.

During the 2000s, the first HD broadcast experiences, as we know it today, adding more and more channels and productions as the years progressed and encouraging the market to adopt a technology that was destined to establish itself definitively in the next decade. Hemos recorrido un largo camino en el que hemos encontrado muchas dificultades (y algunas ayudas inesperadas) que han moldeado la realidad de la implantación del HD en el mercado audiovisual y nos han alejado de las expectativas que pudiéramos tener a mediados de los 2000, cuando la realidad social y económica de nuestro país y, porque no decirlo, del mundo, era muy distinta.

Por medio, hemos tenido que lidiar con la implantación de la TDT, a recesión económica a nivel global que detuvo la inversión en la televisión tradicional (incluso provocó el cierre de algunos canales de televisión), el auge de la banda ancha y la telefonía móvil, el cambio de tendencia en consumption of audiovisual content, la aparición del UHD, las social networks, las video on demand platforms, and much more. All this new panorama undoubtedly forced rethink the path that should be followed, reviewing it every so often and making it difficult to develop long-term plans, especially due to the economic uncertainty that devastated our country for more than five years.

In our market, who more, who less, has been taking steps in the transition to high definition as best as possible, always subject to the budget available, so in the national television market we find a very heterogeneous scene when we come to assess how much ground has been covered and how much remains ahead. There are televisions that have been almost completely renovated and there are many others that still have to face a draft renovation which could include the studies, control central, continuity or others weight areas within its facilities. Surely, the groups of private communication are those who have been able to advance the most in this sense, while some public television they will need to sprint this year to meet the deadline indicated in the National Technical Plan for Digital Terrestrial Television to produce and broadcast in HD natively.

Environments in which high definition is most implemented

Meanwhile, the fiction audiovisual production has established itself in high definition, when not in the UHD, for a long time, thanks to the possibility of consuming this content through cable or internet distribution platforms. If during the transition to DTT there was concern about renewing the fleet of televisions, or the adaptation of the antennas, installed in Spanish territory and there were plans and aid to undertake this transition, without making much noise and in a somewhat anarchic, but very effective way, it has been achieved that in the majority of homes there is a smart TV with internet access with which to consume content in HD or UHD.

This phenomenon, together with the massive implementation of broadband, has fired the UHD content consumption, o como mínimo en HD, a través de las famosas plataformas de pago que todos conocemos u otras gratuitas que ya están ofreciendo contenidos en alta calidad. Incluso se puede dar el caso de que algunos canales que no emiten todavía en HD pongan a disposición en su WEB o plataforma de televisión a la carta los contenidos que emiten en TDT en SD en formato en alta definición para que sus espectadores puedan verlos a través de su dispositivo móvil, ordenador o Smart TV.

Con esto quiero indicar que tenemos dos velocidades muy distintas if we contrast the evolution of technology in traditional and general television, and the evolution it has experienced in the production of content for distribution on new platforms. I will not go into evaluating other media, such as social networks, which move millions of hours of content a day, and where less attention is paid to this debate, but where, without a doubt, work is done on a completely regular basis in HD, UHD or resolutions totally different from the canons of the most orthodox television, all thanks to the HD recording capacity of mobile phones or webcams.

Where to start? Some important aspects to keep in mind

Having looked back, let's look forward, towards the goal of meeting the requirement of the January 1, 2023. To do this, we will review those aspects that may be more critical or relevant when migrating to HD.

One of the main challenges is choosing the file format you want to use.

This is relevant for several reasons, and can greatly influence other aspects, as we will see below. It covers questions such as whether you want to work in 1080i, 720p from 1080p, the codec and the wrapper or wrapper. Throughout these years, there was usually a tendency to work in 1080i, but the fact that more and more content is distributed over the Internet, and therefore displayed on screens that are natively progressive (and that the most common format in UHD is progressive) has meant that there is a tendency to value progressive formats instead of interlaced ones. The downside of the progressive? Requires the double information than its interlaced equivalent. Therefore, twice as much processing, storage and bandwidth are needed for transfer, which will make the project quite expensive.

Infraestructura: 1,5 Ghz vs 3 Ghz

It is important to take into consideration that, when transporting the video over the traditional SDI digital video cable, if you work in 1080p, we will use a bandwidth of 3 Ghz, while if you work in 1080i we will need half. That said, it will be necessary to ensure that all of the teams in the installation, and therefore also the cabling, are compatible with the bandwidth in each case.

Although the most common thing is to work in 1080i (therefore 1.5 Ghz), it is recommended that the wiring, patches, matrices and other switching elements are prepared to work in 3 Ghz. The reason is that, as we have indicated, UHD is progressive, and, therefore, 12 Ghz, in such a way that our infrastructure could be converted to UHD using 4 enlaces HDSDI 3 Ghz for each UHD stream of relatively simple way, while if our installation is only prepared for 1,5 Ghz This migration will be quite complicated UHD reusing existing infrastructure. Almost all HD equipment is already 3G natively and wiring is not necessarily more expensive, so this may be an interesting decision in order to be prepared for the future.

Codec families

Regarding the codec, Sony y Panasonic They took their famous battle over the tape format to file formats, and both have their own family of codecs, ranging from highly compressed files with bitrate low for medium quality productions, up to files with very high bit rates that are ideal for UHD productions of the highest quality or even digital cinema.

Which one to choose? Well, the vast majority of third-party systems support both codec families today, especially if we stick to the HD variants. Here it surely makes a difference camcorde that we think best fits our needs. In this way, if we like the camcorders from Sony, the natural thing will be to adopt a file format from the family XAVC o XDCAM, while, if we opt for the camcorders from Panasonic, we will tend towards the family AVC-Intra.

As for the packaging, in both cases, both Sony and Panasonic work in MXF which, for a long time, has been the most used standard on the market. Just Quicktime It can be considered an alternative today, but it is more widespread in fiction production than in television.

Bitrate

It would be necessary to choose the bitrate in which the content is going to be worked on and stored. The higher it is, the image will normally be of higher quality, but, in return, it will require Greater bandwidth and storage capacity. Therefore, it will be capital to choose wisely the middle ground that adapts to our needs and fits within the available budget.

Another key aspect of the codec is whether it is encoded in intraframe or in Long Gop. He Long Gop is more efficient, having a better subjective quality than the intraframe to the same bitrate, but we tend to overlook that our video editors, servers and other equipment must surely have more processing capacity if we work in Long Gop that if we work in intraframe.

It is not always as such, but it must be taken into account. Getting good advice before choosing is a good idea to avoid disappointment later.

How Ethernet and Storage Are Affected

Likewise, the Ethernet network infrastructure must be scaled to support the transfer of files of the format and bitrate that we choose. So this is another element that is affected depending on the type of file chosen.

He production storage, las camera memory cards, he deep file y any other storage where we host content must have some specific characteristics depending on how much the new files weigh. It is advisable to carry out a complete study of all these storages to ensure that its capacity in hours of material is not reduced once we move on to HD compared to our current systems in SD. If typically, in SD you work with files of about 13 Gbytes per hour when working 25mbit/s, in HD surely let's double o let's quadruple this figure.

Decisions regarding the file format or the infrastructure itself are issues that have surely already been addressed in the most television channels and production centers. Some laggards will be in the process of making the decision, but in general in the market we are aware of the importance of seriously considering these issues and It will not be necessary to delve further into it..

It's not enough to be HD: you also have to look like it

As for the acquisition of HD equipment, those who have been acquiring equipment over the last 3 or 4 years to renew obsolete equipment are very likely to already have HD solutions; In fact, nowadays it is almost impossible to find a device that is only SD. The price of HD equipment today is affordable and SD equipment, largely amortized, can be replaced with its HD equivalent. Therefore, there will be a task, quite obvious on the other hand, of replace old equipment with equivalent ones that already guarantee us compatibility with high definition.

But not everything is being HD. Renewing equipment is not enough. Working in high definition or with HD equipment is not synonymous with the image of our production taking a qualitative leap. When you go from working in standard definition to working in HD, you must take into account some aspects that vary substantially from one environment to another.

Changes in lighting and focus

It will be necessary to readjust, and perhaps strengthen, the lighting and review camera shots. HD cameras could be less bright than their SD equivalents. Also the depth of field It is different in HD than in SD, so there is work ahead in this regard. Luckily, most filmmakers and producers already have experience in HD production and will not need to learn on the fly.

Greater detail in the image

There will be much more image resolution and everything that is presented on the screen must be take care of detail. This includes the make-up, he locker room, he boldness and the decorated. I have heard anecdotes from presenters who said that high definition made them older when they started making programs in HD. Wrinkles that went unnoticed in standard definition HD were clearly visible.

It will also be interesting to renew the scenery on the plates to adapt to the new image format, resolution and detail. It may be a good time for a change of look general and incorporate new elements that highlight and reinforce the image of the programs, such as LED screens, areas on the set where you have virtual scenery or augmented reality, or simply take advantage of renew and update sets or set colors. The budget will mark the scope, but each change will enhance program production. You have to take advantage.

Graphics

With HD, you have more information on the screenTherefore, it can, and is recommended, improve graphics, both that used to inform or enrich the image and that used to promote. These graphics will need to be HD specific; It would be a shame to reuse the graphics used in SD productions.

Adapting the old SD graphics to HD will take a while, but the result will be worth it. However, settling for this adaptation will be wasting a large number of possibilities that HD offers in this sense. There are companies specialized in creating graphics that can advise and help you adapt correctly. economical and professional.

Migrating to HD does not free us from SD: we have to live with it for a long time

Finish converting production equipment to HD It does not mean that the SD is left behind forever. Signals may no longer be handled in standard definition, but you can't change the fact that for years they have produced thousands of hours of content on SD that constitute the assets of each television channel and which, therefore, is material with high value to be preserved. In addition to their conservation, you will often want to reuse for broadcast both the entire programs as fragments, as well as gross cameras that are stored and that will show relevant content for news, documentaries or programs of all kinds.

This SD footage may even be in an aspect ratio of 4:3 and, therefore, requires not only being suitable for high definition, but also adapting the aspect ratio to that used in HD, 16:9.

Thus, in the deep archive of the production center, files will coexist in SD 4:3, in SD 16:9 and in HD. Some assets of the file may be archived with multiple versions, which will require proper tools and of some workflows adapted to the new scenario in which the television channel will find itself so that all this management is effective and does not consume additional handling or processing time.

Business and content management systems

Before transferring all operations to HD, it is advisable to ask yourself if you are prepared to handle new content in parallel with older content. Perhaps it is time to update the systems that manage production from a business point of view, such as the traffic management system or the content manager (Media Asset Manager). These systems, which in principle are agnostic in terms of whether they are working in SD, HD or UHD, are the ones that will allow optimal use of the contents y fine-tune workflows to eliminate human error, streamline processes, reduce the intervention of operators in them and get the most economic benefit from each hour of content produced or acquired from third parties.

We must not forget other collaterals either, such as subtitle files. Surely, subtitle files are available for many contents produced years ago, but be careful, because the same file previously generated for SD content It does not necessarily have to serve the same content in HD. A film or documentary, whose subtitles were generated from an SD media, it will come to us in HD from the distributor the next time we want to broadcast it. This HD media file could have a different duration, los time codes may vary, or there could be other differences that do not make it possible to use the subtitle file directly, so an adaptation of these files will also be required.

On the other hand, if the workflows of the production center, managed by the MAM and other tools, are going to be reviewed, it will be necessary to take the opportunity to integrate those operations that began as something testimonial and that, over the years, have become a relevant part of the center's operations, such as integration with social networks, WEB or Video on Demand: the so-called non-linear flows.

New ways to distribute content

In recent years, we have witnessed an important change in trend in the way of consuming television content. Social networks, OTT platforms, on-demand television, video on demand, and other distribution media complete the traditional linear channel offering.

It is very likely that there are broadcasters that they have figured out how to address the content distribution by these means, but precisely those channels that are still busy finishing migrating to HD are the ones that have probably put the least effort into defining how to distribute content on these media. efficient, integrated and automated way.

Management

Selecting, adapting and distributing content and its metadata, or editorial information to numerous destinations, is a herculean task if you do not have proper tools. For this it will also be convenient adapt the MAM and the trafficking system. Even the news writing system must be involved in these tasks, since a good part of the content will be informative.

The transcoding system may require grow or adapt to provide service to the material that is distributed to social networks or platforms. It is another good reason (apart from adapting SD content for HD production) to grow in this area of file transformation.

Rights

If rights are managed with the traffic system, it will be interesting to have control of content rights that are distributed by OTT/VOD. Good rights management will help generate lists quickly and automatically with those contents that can be distributed, indicating the validity period, the platform, the type of device and the geographical region where they have the right of distribution.

Advertising

Likewise, if the sale of advertising space is managed with the traffic system, it will be interesting to adapt to the way to manage advertising in these new distribution media. The more control you have over these materials by the business management IT tools, the better you will be able to monetize your dissemination in new media. There is a wide range of possibilities that should not be wasted.

A look to the future

As we have mentioned, the implementation of high definition in Spain has gone lower pace than desired. This is a fact that we cannot change, but Yes, we can learn from the mistakes of the past and try to get ahead of the new technological wave.. Perhaps some of those who need to undertake reforms to meet the requirement of producing in HD were able to invest a few years ago and advance the work. Maybe they tried, but they couldn't. It is not our place to judge. However, I am sure that they do wish they had been able to advance some of the work.

Therefore, now it will not hurt to analyze what technology is available y What could the future be in a few years?. Talking to who is ahead in this migration or with manufacturers and integrators is simple and will give interesting points of view to determine what is the best strategy.

UHD/IP uncompressed video

We already know that UHD is well established in fiction production (even in the production of top-level sporting events), and that 8K appears on the horizon. It is also being seen that the uncompressed video over IP is a reality. The new standards of SMPTE and of CLOTHING have made production with IP equipment a reality. In Spain there are already sets completely designed with this technology, and some of the broadcasters who are making the transition to HD this year they have decided to do it con IP equipment, reducing the HD-SDI a something residual in its facilities.

Production automation

Although this is a topic that is not directly related to the migration to HD, yes it is related to the need to renew the equipment in our studios, like cameras, mixers, robotics, servers y graphic systems. It may be a good time to consider incorporating a production automation system that allows you to make the most of available resources and reduce production errors.

Today there are systems that have been on the market for years and, therefore, They are ripe to be implemented in any type of channel: from the simplest to those where they are made complex productions. I recommend taking this into account before starting the renovation.

Immersive audio and HDR

He immersive audio and the HDR They are also technologies that provide an experience to the viewer that until now was not possible. Although both aim to consolidate with the UHD, it is possible to incorporate them into HD e advance work.

Signal and file distribution

It is also a trend contribution of signals over public networks using compressed signal, with low latency distribution protocols, like IS o SRT. Another interesting element to take into consideration, since the use of video files will increase significantly with high definition, is the incorporation of file transfer accelerators over public networks with high latency.

Both when receiving content from external companies and sending it outside, these systems help ensure that the available bandwidth is used as it should. maximum capacity significantly reducing transfer times.

Public Cloud

Finally, the migration of services to public cloud o strengthen cybersecurity These are other aspects to take into account if you want to make an investment that will hold up well over the years. Today, cloud infrastructure may still have a too high cost if compared to an installation on-premises. Even so, if our production requires elasticity to grow quickly for just a short period of time, then it might make sense analyze what the public cloud can offer us. It is possible to deploy a system in the cloud in matter of minutes and start using it anywhere in the world. Undoubtedly it is not economical, but otherwise it probably wouldn't be possible. Therefore, knowing what possibilities we have at our disposal will offer us a wide range of possibilities to choose what is most convenient at all times.