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Re: Are VM and Avinity demonstrating "NGTV" at a trade show later this week?
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Re: Are VM and Avinity demonstrating "NGTV" at a trade show later this week?
The problem with migrating to H.264 is that it requires migration to DVB-C2, which is still in draft. The fact all their STBs (V+ and VBox) are DVB-C compatible means if they were to migrate their entire network to DVB-C2, they'd need to update EVERY box! Frankly I can't see that happening.
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Re: Are VM and Avinity demonstrating "NGTV" at a trade show later this week?
H.264 is a completely seperate encoding technology. Its the difference between DVD and Blu-Ray
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Re: Are VM and Avinity demonstrating "NGTV" at a trade show later this week?
(Sob) :bigcry:
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Re: Are VM and Avinity demonstrating "NGTV" at a trade show later this week?
Remember though that Virgin don't need to migrate to MPEG4 anytime soon
AFAIK by switching off analogue they free up enough space for around 30-40 HD channels |
Re: Are VM and Avinity demonstrating "NGTV" at a trade show later this week?
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Re: Are VM and Avinity demonstrating "NGTV" at a trade show later this week?
reading the developers notes etc, theres nothing great about this avinity RenderCast platform ,it's basicly a very limited subset of XML, CSS and Javascript edited inside Eclipse ,much the same as the old antiquated Liberate CPU cycles swallowing GUI scripting language and interpreter in very limited scope.
"Elements There are not many elements we can use in the RenderCast platform..." http://developer.rendercast.com/doc/Tutorial the super light, tiny yet powerful rebol View (written by Carl Sassenrath of AmigaOS multitasking fame) would have been a far better base for any new expandable TCP/IP/UDP script GUI language in todays world STB/SOC market place http://www.rebol.net/cgi-bin/r3blog.r ---------- Post added at 04:17 ---------- Previous post was at 04:14 ---------- Quote:
you have your video codec, your audio codec and any other data such as sub titles, you place all these inside your container, be it .mpeg,.mp4,or even .AVI container, or Transport Stream (although the TS [Transport Stream]isnt really a true container but close enough for this thread) you then place that on your DVB whatever tunnel , DVB comes in several flavours, each one incremental version basicly allowing you to put more and more data inside a given freq/space.... DVB-C(2) ,DVB-S(2) ,DVB-T(2) ,DVB-H(2), you can put any of your antiquated Mpeg2 only video+audio encoded transport stream or your far better compressable AVC+audio inside any of these DVB types and indeed they do. |
Re: Are VM and Avinity demonstrating "NGTV" at a trade show later this week?
Aye, but while the STBs conform to DVB-C specification, if they were to suddenly push H.264 through them, not only are the STBs not powerful enough to decode it, it also breaks DVB compatibility since no European cable standard has it defined at the moment.
Like I said, migration to H.264 across the board requires an upgrade of *all* STBs (easily a few million out there), but they could at least have the HD channels broadcast to the V+ STBs in H.264 and replace the V+s. |
Re: Are VM and Avinity demonstrating "NGTV" at a trade show later this week?
I've been looking at a number of websites on this subject and I think there is more to this than meets the eye.
A quote from the www.ambarella.com web site, for example: 'MPEG-2 based broadcast content can still benefit from the extraordinary compression gain afforded by the H.264 format if the technology is used in newly deployed appliances while the already deployed appliances remain compatible.' |
Re: Are VM and Avinity demonstrating "NGTV" at a trade show later this week?
I think that is basically saying you can record in MPEG-2 but using H.264 compression which saves space - but the end appliances would still only be able to decode MPEG-2
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Re: Are VM and Avinity demonstrating "NGTV" at a trade show later this week?
Didn't VM invest in some H.264 -> MPEG2 kit for the headends a little while ago? So HD could be pushed around the majority of the network in the more bandwidth frugal 264, only using MPEG2 for the last leg?
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Re: Are VM and Avinity demonstrating "NGTV" at a trade show later this week?
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Re: Are VM and Avinity demonstrating "NGTV" at a trade show later this week?
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seriously, theres really nothing complicated about this. Mpeg2 is one codec, AVC/H.264 is a totally seperate and newer codec (thats got a lot more options and even a lossless mode for pro editing etc, that Mpeg2 doesnt), Mpeg2 is NOT compatable with AVC , you need seperate decoders. the simple answer is if you use an antiquated Mpeg2 codec to encode/transcode your video content and shove it on the wire. you need the exact same codec on the other end of the wire so that your STB can then decode that video stream... and then shove it onscreen. the AVC/ H.264 codec gives you on average 2 and a half times the compression that your antiquated Mpeg2 gets, so you save lots of bandwidth, bitrate , and drive storage space by using AVC, you NEED an AVC decoder codec inside your STB chipset to decode that. NTL were running test of new STBs that could decode both the old Mpeg2 codec, and the far better AVC codec video streams.... TW were later running the so called V+ STBs that only had the old Mpeg2 codec chipset and so it cant decode any AVC encoded video that might one day get pushed down the wire..... TW did this as they needed a quick fix for a STB that could also save the content locally on your STB as sky were killing them by this time.... they went withthe cheapest option and that was the old antiquated Mpeg2 only STBs that their mates in the US love so much and were them off as end of line. meanwhile the world STB markets were moving to AVC SOC STBs that also included the old antiquated Mpef2 codec for the transition..... so , to recap, Virgin media accountants made good short term profits on the books by dropping the far better long term NTL AVC capable STBs, and instead contracting for millions of antiquated end of line Mpeg2 only V+ STBs that couldnt decode the worlds AVC standard..... in effect saving pennys on the CPE V+ STBs, to now need to spend lots of ££££££ for bandwidth costs, new AVC capable STBs that can take this AVC content, and transcoders that can take the industries generic AVC content and convert it on the fly to the higher bandwidth using antiquated Mpeg2 and stuff it on the wire to your MPeg2 only STBs so lived by lots of the US cable operators even today...... ---------- Post added at 06:06 ---------- Previous post was at 05:47 ---------- Quote:
sending AVC to your stb doesnt work as you dont have an AVC decoder onboard any of your virgin media STBs. the newest sky STBs do, for their AVC HD content, as do the new freeview STBS,etc, only Uk VM cable is still stuck on the antiquated Mpeg2 only codec :angel: if VM really cared about bandwidth, and using the internal network " majority of the network in the more bandwidth frugal 264" then yes ,AVC/H.264 would be a good thing, but they can also just use generic Multicasting to the outline storage kit, simple, send one single copy to all client servers listening at a set time over a basic Multicast 224.0.0.1 IP is all they need do, any time, as all the worlds ISP routers and related kit have the generic Multicast protocol as standard and have from day one..... its a real shame they still go out of their way to filter it off from the end users CPE kit sat on your desks, as we could all benefit, and the worlds devs would havea reason to , and could simply retro fit the old "MBONE" and new multicasting protocol code into all the high bandwidth video streaming apps in a very short time (even todays P2p with muticast DHT etc) if the world ISPs just turned it back on all the way to the users.....finally :angel: ---------- Post added at 06:24 ---------- Previous post was at 06:06 ---------- Quote:
and again you cant stream this AVC stored on any Mpeg2 only VM STB as again, the generic driver to activate the STB Ethernet LAN stack and the existing code for basic networking to your PC has not been installed on the VM firmware/middleware, it does exist, but VM dont pay the fees to include it and thats always been a shame, as it might just about manage that network streaming if you pull it with your LAN PCs rather than push it with the internal STBs underpowered SOC/CPU, multicasting with even the underpowered STB CPU might stand a chance though. |
Re: Are VM and Avinity demonstrating "NGTV" at a trade show later this week?
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They can then use the SA V+ boxes for those that don't want HD but do want a PVR Quote:
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Kind of like ZIP files do over the internet ;) |
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