The DLNA standard has a simple objective: to facilitate communication between all your multimedia devices so you can access your music, photos and video more easily. A nice idea
The little world of the DLNA standard
This is where the DLNA standard comes in: the Digital Living Network Alliance. It aims to facilitate exchange and communication between different devices: viewing for example a film in your video camera directly on your TV, or listening to music stored on your computer on the living room hi-fi.
For this, of course, all your devices need to be DLNA compatible. While not all digital cameras are there yet, most recent TVs and HD games consoles are compatible. When it comes to your computer, all you need to do is install the “right” software – if you can find it. We’ll come back to this later on however.
All you need to know is that the DLNA standard allows a server – such as a PC which makes the file available - to communicate with a client – such as your TV or hi-fi system.
A very mouthwatering prospect: "all my multimedia files are going to available on all the peripherals in the house".
We’ve been testing DLNA compatible TVs for long enough to tell you that there’s quite a gulf between the theory and practice. Just take a look at the spec for the standard and you’ll start to see its limitations:
- For audio, compatible formats are limited to AC3, AMR, ATRAC3, LPCM, MP3, MPEG4, and WMA. No DTS or HD formats then!
- For photo, we’ll have to make do with JPEG and PNG.
- For video you get MPEG 1, MPEG 2, MPEG 4 Part 2 (therefore DivX), MPEG 4 Part 10 (and therefore H.264), and WMV9. No VC-1 (WMV10)!
- MPEG PS/TS, MP4 and ASF containers are accepted but there’s no MKV nor AVI!
This makes the standard too restrictive as it limits transmission of flows of data to well-defined formats. Using a communication system that simply transits a flow without reducing it to formats would have been a lot more time-proof and practical. This is indeed what you get with the Universal Plug’N Play Audio/Video (UPnP AV) standard that the DLNA standard uses. DLNA simply adds additional constraints to a system that was much more flexible.
Manufacturers have their custom versions
On top of this, manufacturers are implementing the standard pretty much according to what suits them. Sony is a good example as it has been selling audio and photo DLNA compatible TVs for a long time. Video was excluded which means these TVs aren’t truly DLNA compatible.
Other brands have been extending compatibility to formats that aren’t included in the standard; the server still has to be compatible for these formats to be compatible with the client (here the television).
We also note that the formats that are supposed to be DLNA compatible aren’t all accepted by all peripherals.
This alone would be enough to undermine the standard and question its utility. And that’s not all! There’s another point that needs covering: simplicity of use.
Complicated to set up
In spite of what we were promised by the DLNA alliance and manufacturers, usability isn’t really up to speed. Worse still, getting communication between a client and server set up can sometimes be a nightmare and simply prooves impossible for those who don’t have a minimum of knowledge in terms of multimedia files. The problem lies in computers themselves and in most cases computers will be used as the servers for household DLNA devices – often TVs. For your computer to work as a server it needs a piece of software that generally comes from the TV manufacturer. Unfortunately this software is often pretty poor. Various solutions have been developed by communities or companies (the best known and most used are PS3 Media Server, Twonky Media, Tversity, Nero MediaHome, or Windows Media Connect from the Windows Media Player) but they aren’t available to all users and, even if they were, they aren’t perfectly conceived.
Addition Thursday 25th February 2010:
Following the publication of our article, we had the opportunity of talking with Olivier Carmona, member of the DLNA board of directors and representative of the French company AwoX. The conversation led to this addition:
Our article seems to have underplayed two points that give a fairly good summary of the DLNA standard and its philosophy:
- The standard has first and foremost been created for both those with and without technical knowhow. Certain limitations of the standard are the result of a desire to make different devices interoperable. In contrast to other systems, the DLNA standard steers clear of forcing the user to carry out complex settings (IP address, configuration of Samba or NFS filesystems…). However, as we mention above, this limits compatibility to a defined number of profiles (200 to 300) so as to ensure a common basis for DLNA devices. It also has to be said that the question of rights limits the usage of certain formats which therefore aren’t DLNA compatible. The standard isn’t however limited simply to the use of multimedia players as it also, for example, aims to allow you to send images from your mobile phone to your TV screen, or to control your music throughout your house, room by room, from a tablet. DLNA aims to make the various potential usages better known but still has a long way to go.
- In addition, with respect to the ‘’multimedia server’’ part Olivier Carmona says that Windows 7 allows full use of the DLNA standard. The server built into Windows Mediaplayer 12 is indeed very powerful and has been developed to ensure maximum compatibility with DLNA devices. It even allows transcoding of formats that aren’t included in the standard. There are of course still limitations, such as the impossibility of handling subtitling.
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