Tag: content delivery

DLNA 4.0 to support server-based media transcoding

Article – From the horse’s mouth


Synology DiskStation DS415play NAS with media transcoding - Press image courtesy of Synology

Synology DiskStation DS415play – demonstrating the value of transcoding content to provide to DLNA devices

Press Release

My Comments

An issue that can easily beset DLNA / UPnP-AV content-delivery setups is the fact that digital-image, audio and video content can be delivered in newer file formats and that it could be packaged for high-quality setups. A case to point could be 4K UHDTV video content which would work with the newer 4K UHDTV sets; or you could have audio content packaged in the FLAC lossless-compression file formats rather than MP3 or WMA file formats.

But the problem that exists is that you will likely to have older or cheaper equipment that can’t handle the higher-quality content types. Some devices that can handle the higher-quality content type may not be able to handle it in the file format it is delivered in unless the device’s firmware was updated to take the newer filetypes. Typically, this may ruin the experience because the device will typically throw up a confusing error message or show nothing.

A few UPnP-AV / DLNA Media servers do support some form of filetype or content transcoding with some Synology NAS units implementing this functionality at the hardware level. But there isn’t the ability to be sure that the NAS, broadcast-LAN tuner or similar device provides this kind of transcoding. The new DLNA 4.0 specification mandates that compliant server devices have to transcode the content that they serve if the client device can’t handle it directly.

The questions worth raising about this required function is whether this applies to filetype transcoding only or if it also includes functionality like downscaling a 4K video to Full HD for existing HDTVs for example. It shouldn’t also be about whether the transcoding takes place in the background for stored or downloaded media or only in a real-time fashion whenever legacy equipment wants the resource, something that would work with broadcast-LAN applications.

As far as NAS and DLNA media-server software design goes, one differentiating point that will exist would be the ability for the hardware and software to implement hardware-based transcoding. This is where a separate processor and RAM, like a GPU setup, is provided to transcode video content rather than the device’s main processor and RAM being used for the task. It is similar to what would happen if you use a computer equipped with a discrete video card or chipset to transcode some video content and this permits the main processor in the NAS to continue serving the files without having to transcode them at the same time. At the moment, the Synology DS416play, the successor to the DS415play which was the first NAS to offer this feature, is the only one that implements hardware transcoding.

Personally, I would like to see these devices offer transcoding for QuickTime and Motion JPEG video as used by some digital still cameras, and FLAC and ALAC lossless audio which is now valued as a high-quality audio format for “ripping” CDs or buying download-to-own music. This is because these formats are not universally handled in the DLNA network media sphere.

Other functions that are part of this version include catering to IPv6 networks which is fast becoming the way to go, inherent support for 4K and HDR video content, the requirement for a DLNA MediaServer to expose HD variants of more video filetypes and the VIDIPATH functionality being baked in to the standard which would be important especially for Pay-TV applications.

Why we need download-based services for video content

Legal download-based video ecosystems could yield frustration-free viewing of video files

Legal download-based video ecosystems could yield frustration-free viewing of video files

Most video-on-demand services, whether transaction-based like iTunes or subscription-based like Netflix, are based on the concept of streaming. This is where the content is delivered in real-time from a remote server to your smart TV or set-top box via the Internet.

But streaming has a key disadvantage. It is totally dependent on the quality of the Internet connection and your equipment and can cause a poor viewing experience if there is reduced bandwidth due to situations like a poor DSL connection or a highly-busy network; and is a situation I have seen for myself with Apple TV and the iTunes video-on-demand service.

Similarly, streaming can be at a disadvantage when you are using mobile devices and are viewing the content in a mobile context like entertaining your kids with some videos on a long road trip or whiling away the train commute with episodes from your favourite TV shows. Here, the Internet connection may not always be reliable because you may be moving out of your mobile-broadband service’s reliable reception area frequently during the trip, something that would happen as you enter a tunnel or drive further out in the country.

USB external hard disk

USB hard disks – could be part of a download-based video ecosystem

A download-based video-content service would work in the similar way to iTunes or Amazon music services where you can buy and download songs or albums. This is where, as part of the transaction, you download the movie or TV show to local storage and play the content from the local storage.

The local storage could be a USB hard disk which you download the content to using a regular computer, then connect to a TV or video peripheral for playback. On the other hand, it could be a network-attached storage device which streams the content out to a smart TV or video peripheral over the home network. As well, it could be storage integrated with a viewing device like a tablet, laptop or smartphone which you use to view the content when you are “on the road”.

Key issues

Content protection

NETGEAR ReadyNAS RN1040 NAS press picture courtesy of NETGEAR America

This ReadyNAS could serve as a household movie library

There is a big genuine fear shown by Hollywood with download-based services where the high-value video content could be replicated in an out-of-control way. This is being examined by the Secure Content Storage Association who are looking towards secure authenticated storage for these files. They are pitching it at digital download, “physical+digital” delivery, retail kiosks amongst other digital-delivery business models along with access to newer remasters of the same content for those of us who already have an existing copy.

Business models

Any content-protection system like SCSA would have to support a range of business models, primarily transaction-driven models, such as the two outlined below:


Typically, the main business model that would be associated with a download-based service would be a “download-to-own” model where you download the title and watch it for ever, similar to buying the content on a VHS videocassette or a DVD or Blu-Ray disc. This would be more or less associated with the “collectable” model where you buy favourite movies or TV serials that you want to come back to.

This can be provided by a “digital-only” service where you just download the content from an online store or as part of the supply of the content on a physical medium like a DVD. It can also extend to the supply of USB memory keys or USB-connected hard drives that are full of a collection of video titles, a practice that has been done with Bob Dylan’s album collection which was dumped to a USB memory key shaped like his quintessential harmonica and sold as a collectable. An example of this could be a collectable USB hard drive loaded with remastered copies of all of the episodes of a classic British or American TV sitcom and this hard drive is styled to reflect the tone of that sitcom.

As well, this could support the gifting of content where you can effectively give your relative or friend a licensed copy of the content whether you own it or not. This would have to work in a similar manner to how you can use iTunes or Google Play to give someone a copy of a game or other app and the recipient gets alerted to this content that is available for them.

Time-based rental

A question that may crop up with some of us who lived with the video-rental concept is whether the SCSA technology will support the ability to “rent” the titles for a short period like 24 hours, a weekend or even a month. This business model was appreciated as a way to get an evening’s, weekend’s or week’s worth of entertainment in a cost-effective manner and assess whether that movie could be worth collecting.

Here this model would allow you to download the title and view the title within a certain time period, including a requirement to commence viewing within another time period like a month.

A variant of this concept could be a view-based model where the time you rent the movie commences from when you start viewing the actual content or you are charged per complete viewing. It would earn its keep if you are “piling up” on content by having it download overnight then commence watching it over a time period like a vacation break. It would also play well with households whose content-viewing sessions are likely to be interrupted frequently or for a long time. The concept can even allow for “rent now, purchase later” models where you may rent a movie to see how you like it but then choose to buy it if you consider it of enduring value.

A file-based rental model has an advantage over renting that VHS tape or DVD where you can extend the rental period or choose to rent the same title again without dealing with the packaged medium. Similarly, this model could allow one to convert a movie rental to a purchase which can come in handy for titles that one considers “enduring” such as a live concert or a movie that has stood the test of time.

Subscription-driven options

A “download-to-own’ or “time-based rental” business model can be tied in with a content-subscription option where you have content delivered at regular intervals.

Such setups could encompass a business model similar to the book, music and video clubs popular in the USA where you had a random choice of content delivered on a regular basis. This was typically driven by a requirement to purchase the delivered content or other content.

Or it could be based on subscribing to episodic content or a similar collection whereupon the new content is downloaded as it becomes available. An example of this could be to have episodes of a TV show available for download as they become available with the user choosing to “buy” or “rent” the current season or a particular season. Similarly, Disney or Warner Brothers could offer their collection of those unforgettable cartoon “shorts” that during times past constituted Saturday morning TV or the start of a cinema session in varying rental or purchase packages with each “short” being downloaded as they become available.

Such a setup could allow for automatic download as new material becomes available or users instantiate the download themselves from the electronic shopfront or an email-based update.

Simplified content management

Acquisition and downloading

Another question yet to raise is what procedures are necessary to have a title ready to view on a download-based video service. This includes the use of an electronic shopfront for browsing the titles available to buy or rent, completing the transaction and downloading the titles. It also includes the ability to support network-based installation where you could have the titles downloaded to a NAS.

Here, this may be about being able to remotely determine installation or deployment folders on a USB hard disk or NAS from the electronic shopfront application, along with having such applications work across smart TV, mobile, desktop and games-console platforms. The native apps for desktop or mobile platforms can also support “checking out” of user-selected content to mobile devices or removeable media.

The UPnP AV / DLNA specifications could be amended to support transfer of content to network storage devices by allowing shopfront applications hosted on smart TVs or video peripherals to discover where to put the content. This would also require the ability to commence a transfer session between the content service and the NAS independent of the application being constantly run.

There needs to be an ability to handle larger orders like content collections or multiple purchases / rentals so as to download the content in a bandwidth-optimum way. This could involve a download-priority mechanism where some content is sequenced while other content is downloaded concurrently.

I have also raised before the issue of simplifying the process of adding file-based content held on physical media to network storage. This would apply to so-called “disc-to-digital” services where you can have a movie that’s on a DVD or Blu-Ray available as a file as well as content collections delivered via a USB memory key or hard disk.

Exporting content for portable use

Another process that will also surface is where you export content to another format such as a lightweight format for use with portable devices like tablets and smartphones. This would involve converting the video content to a format suitable for these devices then copying it out to the player or storage device.

It would also include synchronising content to an in-vehicle infotainment system so it can be shown to the kids in the back seat of the SUV or minivan through the long road trip.

Yet another issue that has to be sorted with rights holders is the concept of what is your home realm. This would be encompassing secondary properties or properties that you use on a temporary basis like holiday homes or, in some parts of Europe, summer houses as well as your main home and portable devices that the household uses. Once this is sorted out, it could mean that content is available across this logical realm with it being downloaded to NAS units kept at these remote properties.


The entertainment industry has to look at download-based distribution as another way to distribute video content rather than just streaming out the content. This could make electronic sell-through, disc-to-digital and related business models built upon videocassettes, DVDs and Blu-Ray Discs viable for file-based video content.

Delivering purchased content collections to the home network

Apple and others may have us streaming content on a temporary basis in to our homes after we subscribe to them or another content provider but we will still want to download content to our home networks. This is so we can believe that we really have bought and owned the content rather than perpetually renting it. As well, an increasing number of content providers will take advantage of the digital environment to affordably distribute content under a “to-own” philosophy where we can buy that content in a digital form for cheap.

An example of this would be a few of the US’s well-known magazines, especially National Geographic, offering their back-issues as a collection of PDF files on a CD collection or a USB hard disk. Similarly, we would purchase digital albums of our favourite recordings from various online stores including iTunes. As well, when I went to a travel fair on Sunday 19 February, a country provided an optical-disc-based “slide collection” of images of that country at their stall.

The question that many will ask is how can it be made easier to deposit this content so it is available across the home network. Here, we could copy the files to a public “media folder” on a network-attached storage unit that is on the home network. But we would have to know where that “media folder” exists and how we should present the media to the network. As well, we would need to make it easier for a collection of PDF or other “electronic-book” files to be discovered on a mobile computing device such as a tablet.

A secure network installation routine for small networks

There typically are installation routines in place for provisioning software to computers but these look after putting the software in place on the computer from a user-carried, network-hosted or downloaded package and making the software discoverable in the computer’s operating system. The practice is also similar for delivering software updates and add-ons for network-attached storage devices and other similar devices.

Most media that is purchased online for download is typically downloaded to the user’s regular computer or, in some cases, their mobile device and manually copied to the network-attached storage using the operating system if it is to be shared. It also holds true for digital photos that are downloaded from one’s digital camera or content held on a “carry-through” physical media container like an optical disc or USB memory key. This can be a pain for people who don’t have much computer experience or patience.

One way to make this easier would be to provide a secure simple network installation routine for content collections. This could be based on the routine knowing common variables that represent the content collection and where particular content classes should go. It could manifest in a download handler associated with an online music store that knows the location of the download-music folder on the NAS.

Such routines would need to have a high level of security in order to prevent questionable software from being made available to the network. They will also have to properly support and handle permission systems that are part of most network operating systems.

These routines could allow the copying of “new” media files from the source to particular folders or, in some cases, mount the content collection to the NAS’s file system if it was in something like a USB hard disk such as the National Geographic example. Then it would force the media to be annexed to the index created by the NAS for searching and browsing the media. Of course, there will be the desire to install a skinned microsite which allows one to browse or search a media collection and this would work if the NAS uses a Web server.

Making “electronic-hard-copy” formats discoverable over the network

With DLNA at its current point, it is now feasible to provide images and audio-visual content to nearly every network-enabled audio and video player, allowing users to search or browse for the content they are after. This can be done using the device’s control surface or a control point hosted on another device and the browsing and searching can be performed against many different attributes such as the artist, title, date, user-assigned keyword or genre or a combination thereof.

But this concept hasn’t been extended to the “electronic hard-copy” document that is used for e-publishing. This will become more relevant as we purchase e-books and similar documents and create our own “e-libraries” and store them on NAS drives on our home networks. This will be of importance as large collections of works are made available in electronic hard-copy format for sell-through download or supply on a physical medium like a USB hard disk or optical-disc collection.

Here, PDF, ePub, XPS and other electronic-hard-copy files could support standardised metadata and the DLNA specification could be extended to permit discovery of content held in these electronic hard-copy formats. This would allow people who use e-readers, tablets and smartphones equipped with the right software to discover and download this material to these devices without having to know the file hierarchy of a NAS or use file managers to “pick up” the content. This software could then be integrated in to these devices in a similar manner to how DLNA media player software is becoming de rigeur for the standards-based tablet or smartphone.


The main issue here is that to be comfortable with newer content-delivery methods, we need to he able to do what we used to do in acquiring and annexing the content to household-common content pools so that all members of the household can gain access to the material. This then has to be made easier to d when it comes to file-delivered content especially for people with limited computer skills and what has been made available for photos, music and video content must extend to e-books and similar content. It also must allow the use of standards-based technology that doesn’t tie the user down to a particular vendor.