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BBC Radio Drops WMA For MPEG-DASH
gbjbaanb writes: The BBC has converted its legacy WMA (Windows Media Audio) streams to the "industry-wide and open source" MPEG-DASH format. While this has left some users of old devices unable to receive the broadcasts, the BBC claims the use of WMA was "prohibitively expensive to operate"when existing licence agreements ran out. The BBC says that they are working with "radio industry and manufacturers towards using just one standard."
Yay.
Firstly, HTTP is the simplest form of internet delivery â" it is how the vast majority of web sites are delivered. Aligning audio and video delivery with this is much cheaper as it doesnâ(TM)t rely on proprietary streaming formats that require specialist delivery mechanisms. Instead we can make good use of much of the work that has been undertaken in optimising and caching the delivery of HTTP.
BBC claims the use of WMA was "prohibitively expensive to operate"when existing licence agreements ran out.
ha ha ha ( said with a sarcastic tone )
MP3 is a compression codec. OGG is a container format. MPEG-DASH is a standard for how to do bitrate-adaptive streaming over HTTP. They're all completely different things.
MPEG-DASH is codec-agnostic, and does not require or imply any specific codec. However, since it's intended for audiovisual streaming (rather than just audio), and since it's done under the auspices of the MPEG, h.264/AAC are the obvious codec pair to choose. There is nothing stopping MPEG-DASH from being used to stream something like VP8/Vorbis or VP9/Opus... and in fact the WebM project has documentation detailing exactly that.
Missing from most of the articles on this, including the ones on their web site, is that they used to employ a senior Microsoft media guy who, unsurprisingly, set about converting everything to Microsoft Media formats - Ashley Highfield. Here's a 2007 article with a section of the controversy
BBC used to have one of the more progressive approaches to media with early mp3 streams, Dirac codec research...it then just stopped. Nice to see them get back towards the rest of the world - next step, please go HTML 5 video on the site as well and then we can avoid Flash.
Thank you. I had to google for more info on MPEG-DASH; kind of surprised to have never heard of it before on Slashdot before today.
moox. for a new generation.
AAC is by far the best audio codec that I have come across .. a 64 kbps stream sounds like 128. Too bad its proprietary
Try Opus @ 64Kbps compared to HE-AAC @ 64Kbps: http://www.opus-codec.org/comparison/
I'm surprised you expect to hear about it here. Most people here seem to care about the codecs and whether they're free. DASH doesn't really care about codecs and really just defines how you create and use adaptive streams and is based on existing codecs/formats. It only standardised relatively recently and it's going to be big (but hopefully transparent), for example: http://www.dash-player.com/blo.... Expect to see it as a vendor neutral alternative to things like MS SmoothStreaming and even Apple's HLS, although the later requires you to have a player with your own decoders if you're sending more than a certain size to iOS devices.
That said, most implementors are doing AVC or HEVC with AAC in a fragmented MP4 container. VOD content is probably one file per stream and live is multiple files fragments) per stream.
This was really badly publicized. We listen to BBC Radio 3 over the internet in the mornings; our house is situated in a dead zone for over-the-air signals, so we're pretty much stuck with streaming. One morning last week, with no warning, came a repetitive announcement saying that the BBC had discontinued WMA and to "contact your device manufacturer". Our radio is manufactured by Pure, and we have been using Radio 3's direct streaming URL because Radio 3 repeatedly drops off Pure's database for days on end and consequently becomes unavailable. The direct URL, on the other hand, has been very reliable up to now.
The BBC say that they make MP3 streams available for all their channels. I couldn't find one anywhere on any of their websites, so I wrote to them and asked them what it was. Here's what they told me: "We are currently only sharing links to our new streams with aggregators and device manufacturers. We are not currently making the links for the new Shoutcast and HLS streams publicly available. Whilst it was previously our policy to share these we found that we could not assure quality this way.". So not only have they discontinued the old streams, they are deliberately hiding the new ones! This is nonsense. The BBC apparently doesn't want anyone to actually listen to their broadcasts! (I did eventually find a viable MP3 feed from radiofeeds.co.uk).
Now we get to bit rate... It was much ballyhooed a year or so ago that BBC Radio 3 was broadcasting the highest quality classical music available because they supplied a 256 kbps stream. It now seems that the maximum available is 128 kbps. Fine for portable radios, but I really don't think this is step in the right direction.
Looking at Dashif.org, I notice the following:
MPEG-DASH Highlighted Features
Advertisements can be inserted as a period between periods or segment between segments in both on-demand and live cases.
I'm a cynic, and I'm getting very suspicious about the suitability to this tech to the BBC.
This is why BBC Radio 5 Live stopped working using the XiaaLive Android app? Is there a new URL I can use?
"AAC is by far the best audio codec that I have come across...Too bad its proprietary"
Proprietary in what way? It's an ISO standard, among other things:
https://en.wikipedia.org/wiki/...
A.
...bringing you cynical quips since 1998
Due to Auntie Beeb's rampant xenophobia, those of you outside of the UK may have to use a proxy or VPN to spoof a UK IP address.
It's not xenophobia, you silly twit. The BBC is funded by UK licence payers, who have no obligation whatsoever to provide free content to people in other countries.
To have a right to do a thing is not at all the same as to be right in doing it
Flash is a security nightmare that we recently suggested deserves to rot in an unmarked grave.
No, you'd better mark that grave prominently. Don't want anyone to unearth it again by accident.
Someone had to do it.
And more importantly they sell the rights to their content outside the UK and those rights holders expect that their ownership is exclusive.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
It's an iso standard, but what he means is that you need a licence to distribute an AAC encoder/decoder (unless you distribute it as source code I believe).
The problem is not that they are getting rid of wma. The problem is they have dropped acc from Shoutcast and plan to turn off Shoutcast altogether in the next year or so. Since Shoutcast is supported by all Internet radios, and dash is supported by no Internet radios (please let me know if I'm wrong) it means that BBC radio is getting out of the business of streaming to Internet radios, starting by dropping support for Listen Again now, and eventually dropping all support. Too bad. I'd happily buy a radio that supports the new protocol, but they don't seem to exist.
Too bad [AAC is] proprietary
Proprietary in what way? It's an ISO standard
Probably "proprietary" as the antonym of "free software". ISO standards can be encumbered by patents, and these patents can be licensed under either royalty-free or uniform-royalty terms. AAC and other MPEG codecs tend to carry a uniform royalty, and free software cannot implement any process with a nonzero royalty. Opus, on the other hand, is royalty-free.
It seems like many internet radio providers are dropping Shoutcast support, usually quietly/silently, and expecting you to use a proprietary app or DRM-based player to access their content. They may as well shoot themselves in the foot.
Dropping Shoutcast support today is akin to commercial radio stations dropping AM in favor of FM back in the 1960's (note: they didn't, some simulcasted but eventually dropped FM until it really took off in the late 70's/early 80's when the penetration of receivers reached critical mass).
Sure, there are players and radios that support newer formats, but every player and tons of applications support Shoutcast. Unless, and I know this is a huge stretch, the big media conglomerates don't want to compete on an open directory of stations that lets anyone with a computer and internet connection become a "broadcaster", and are trying to kill it off by removing their content from it?
Nah, couldn't possibly be that...
Why don't they just offer different streams at different bitrates?
Because the user doesn't know in advance which bitrate to choose. For one thing, non-technical users don't know what a bitrate is. For another, the throughput and latency of a particular user's connection to the Internet change over time, and interrupting the stream when the connection quality declines causes a poor user experience.
Based on this post, it looks like the BBC radio audio stream is encoded at a constant rate of 320 kbps using AAC-LC, delivered in the MPEG DASH container, and implemented in HTML5 using Media Source Extensions (MSE).
It is not clear to me if the BBC radio audio is being carried in MPEG DASH as MPEG-4 file format fragments or as an MPEG-2 Transport Stream, but I would suspect for audio-only it is MPEG-4 file format fragments.
The BBC story and blog states that many R5 Live Sports commentaries are 'blanked out' because it is available worldwide and the BBC do not have the world rights. As it is radio, the sound consists mainly of the commentators talking, and these are BBC commentators so in effect the BBC is saying that they do not own the copyright in the words spoken by their employees (intended for broadcast) as part of their employment. Or to put it simply, the BBC own the copyright to the commentaries made by their commentators - so they also have the right to broadcast (whether by radio or IP) wherever they choose. So this is a fatuous argument.
I'm sure the French will now finally pay up in order to listen to your glorious BBC.
Now BBC.co.uk and bbc.com need to drop Flash video for HTML5.
Remember the 'world wide' part in WWW.
"I'm not much interested in interoperability. I want substitutability. I want to be able to throw your software out."
The only good AAC encoders (Apple, Fraunhaufer, and debatably Nero) are proprietary. There are open-source encoders, but the quality is so poor that they aren't worth using.
This doesn't even take into account licensing/patent issues, which I believe come into play as well.
Prohibitively expensive> Not for (one of) the most monopolistic and richest companies in the USA. Thank you BBC for telling MS to shove their license up it. BTW who is ready to pay a yearly license for win10? I'd rather use win98SE with all those cracked free programs remember how great they were? And how those "free programs" made MS a predominant computer OS. Then they had to make WINXP DRM crappy and nothing you had or bought like musical keyboards from creative worked. That is unless you bought the proper CDs for $250 to learn you really couldn't use them. Forget about "trial versions." Applications for audio and MIDI compiling and other things? But at least we were 'productive' right? Bullshit.