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I suggest looking at the result of codec comparison in https://tech.ebu.ch/docs/tech/.... The EBU performed A/B comparisons with different lossy codecs for 5.1. They trained people in how to spot the difference in challenging areas to encode, and then evaluated various codecs with challenging pieces.

Keep in mind that FLAC is typically 3x as large as 320kbps, and storage sizes are quite huge now.

I'm reasonably impressed with what they've got, except that the performance blows, and slows editing way down... It at least allows using existing references (which most people don't know how to do), and will try to auto-complete links to other articles, but that's about it.

With references in particular, it only inserts the <ref> tags, leaving you complete freedom to type anything, or nothing, in there. Compare this to ANY of Wiki reference templates, where references are named, and there's a strong syntax enforced for dates, names, titles, publisher, and tons, tons more. eg.

<ref name=ebu_surround_test_2007<{{Citation | last = B/MAE Project Group | title = EBU evaluations of multichannel audio codecs | pages = | date=September, 2007 | publisher = [[European Broadcasting Union]] | url = http://www.ebu.ch/CMSimages/en/tec_doc_t3324-2007_tcm6-53801.pdf |format=PDF| accessdate = 2008-04-09 }}

The big problem with Wikipedia is the HUGE number of tags, templates, categories, etc., and the editor does nothing to introduce you to them when you don't know about them, nor help you find and insert the one you're looking for.

When editing, I'd be constantly doing free-form searches, to find useful tags, syntax, and just exploring around similar pages to find good categories.

Rather than WYSIWYG, they'd do far better just to have a few hierarchical menus, that'll insert the proper wiki code for you, rather than constant copy/paste from template pages... For example, the ref button is pretty useless... But a ref drop-down, with sub-options like "Book" "Web" "Magazine" etc., would be far more useful. Of course if they could make a pop-up form, with fields for all those values, and automagically guessing which type of ref you've input, and which template is best, would be far better still.

Or something like that. It's not only about average loudness; it's also about dynamic range.

I'm a broadcast tech at a license-funded TV station in Norway, so we don't have to deal with advertising volume jumps, but in general, we aim to follow the already-established EBU recommendation 128, which specifies loudness.

Indeed, the spec is publically available: http://tech.ebu.ch/docs/r/r128.pdf

Why? You've expanded only on the sound quality argument - could you name a combination which you believe exceeds the quality and graceful degradation properties of FM, along with an independent study supporting your assertion? Even Dolby, the Via subsidiary of which handles DRM licencing, sells it as "near-FM quality".

DRM+ will probably mostly use 50kHz channels which should offer about 300kbps bandwidth. The standard doesn't prohibit using more though, so you can go 100kHz and stream FLAC (although getting FLAC support into receivers might be a challenge, and FLAC is difficult for streaming anyway).

There is a risk that people will go 64 kbps MP3 or worse, but you can't blame the standard for that.

Degradation is fairly binary -- either you have reception or you don't. I consider that a feature.

Erm, up to 4 data streams per MUX, no? Or is only one audio stream supported?

Traditionally you'd only do one audio stream per MUX in DRM. BBC World Service DRM has this to say: " The main data channel can carry up to four simultaneous streams. This is not intended to provide a service multiplex such as DVB or DAB provides – the channel is not large enough for that."

The Society for Motion Picture Engineers has already gone to great lengths (in coordination with the EBU) to create some containers, such as GXF, and MXF.

MXF is already being used as part of the Digital Cinema Initiative (DCI) spec that delivers standardized digital cinema content to theaters. There is already a registered MIME type for MXF.

By the way, you can be mad at Microsoft and their love of Windows Media, but then there is Apple Final Cut Pro and QuickTime (ack!).

HE-AAC isn't really an improved codec. It's simply AAC with high-frequency sounds added to it (AAC+ SBR).

You're neglecting to mention parametric stereo (PS).

So, no, you're not going to get a smaller file with HE-AAC, but you are going to get better high-frequency content like cymbals, flutes, et cetera.

This is nonsense. If you got better sound quality at a given bitrate, you simply reduce the bitrate further until you get approximately the original quality level.

Especially at low bitrates. AAC sounds really bad at 16 kbit/s, like listening to music over a phone, but HE-AAC (AAC+SBR) sounds as clear as FM radio thanks to its high-frequency preservation.

SBR isn't about preserving high frequencies AT ALL. In fact it's about eliminating the high frequencies completely, and using the low frequencies to guess/approximate what higher frequency content might sound like.

It's a clever perceptual trick (much like intensity joint-stereo), but like most similar tricks, it only works on low-quality content. Once you start increasing the bitrate to the point where regular (low complexity AAC) compression doesn't do terribly, such tricks start to do... worse, and are best simple disabled.

This isn't something I just made up on the spot. See: http://www.ebu.ch/en/technical/trev/trev_305-moser.pdf

Anybody who has owned an early-production MPEG2-encoded Bluray versus a MPEG4-encoded HD-DVD, can tell you that's there's less macroblocking with the newer codec.

Anyone that has owned a dog can tell you that they're better than cats...

Anecdotes are useless.

The fact that there are crappy MPEG-2 encoder out there, and good MPEG-4 encoders, DOES NOT imply that MPEG-2 is therefore, bad.

With MPEG-4 AVC/H.264, you should NEVER see macroblocking, because there's a dynamic in-line deblocking filter defined in the spec... Its required.

However, using a deblocking filter (on MPEG-2 videos) may get rid of the blocks, but that doesn't mean the picture is going to be better. You generally trade blockiness for blurriness, and H.264/AVC is no exception...

To date, I have not seen any LCD or Plasma monitor that can perform as well as certain projection D-ILAs in terms of the combination of luminance ranges, good black levels, contrast ratios, gamma accuracy, viewing angle, and coverage of the Rec. 709 gamut. But don't take my word for it, here the Plasma Display coalition admits they can only cover 80% of Rec. 709 with their best displays, with many more falling in the 75% department.

From a digital television perspective I am much more interested in monitor gamut effectively covering the Rec. 709 color space, because that is all I can put on TV. Sure, it's OK to have extended gamut outside Rec. 709, but if you can't actually cover all of Rec. 709 gamut I don't care if you cover color outside that space. Similarly, I'm sure digital cinema people want the DCI gamut covered well first before having coverage outside that gamut.

On the LCD side, the production lines are changing so rapidly that two versions of the same type of panel from different months will have different results. I have seen a $300 Dell LCD computer monitor perform better than some professional television LCD displays that are priced 10 times as much.

My suggestion is to measure displays yourself, and ignore marketing literature. Of course, you need a good broadcast engineering lab to do that, not all networks have such a thing...

If you want to know what you need in a good monitor, see the EBU User requirements for Video Monitors. SMPTE is working on a set of recommendations as well.

I'm hoping that OLED displays will come to the rescue, but it will take a while for them to come up to needed sizes and maturity.

If you want viewing angle, you're distorting the picture significantly in space, so losing a little luminance or color fidelity shouldn't be too big a deal

In the broadcast engineering world, we like to have two people looking at a monitor at the same time to be able to see the same color & luminance on a pixel. Plus in a broadcast control room, you aren't sitting on a sofa, you may be moving around the room but needing to occasionally look back and need to be able to see what is going over the air to millions of people.

Some of the LCD monitors I've seen have good horizontal and vertical viewing angles, but it turns out that any offset in a diagonal direction is unusable for critical viewing.

You are right about CRTs. Professional-quality HD CRTs are basically no longer made. You plopped down $50,000 for one five years ago, but now there are none except in the used market.

Here are the user requirements for reference monitors from the EBU.

I should add that plasmas in particular have really truncated color gamuts. They cannot represent all the Rec. 709 colors at any reasonable brightness, thus they tend to
"stretch the greens" which the eye is more sensitive to in order to look bright. Many plasmas also have a "turn-on jump" from a totally black pixel to one that has any light output that tends to accentuate noise in dark areas.

Here is paper from a demonstration done by EBU at IBC last year, where they showed 1080p, 1080i and 720p compressed with AVC at different bitrates (from 16 down to 8Mbit/s) next to each other.

The bottom line: 720p looks remarkably better than both 1080p/i at the bitrates the broadcasters are believed to use on their content.

- e

For example, DVB covers Terrestrial, Satellite, and Cable, but you have to buy AN ENTIRELY DIFFERENT CARD FOR EACH ONE.

That is an implementation issue. The DVB systems use a different modulation optimized for each medium, and you need a separate tuner for each of them.
However, the demodulated bitstream is the same and from the tuner on, the hardware is the same.
Receivers are available that have their tuners seated in slots, and that can accept a user-selected mix of DVB-S, DVB-C and DVB-T tuners.

E.g. this one: http://www.dream-multimedia-tv.de/english/products _dm7025.php

ATSC also has (long had) standards for broadcast, cable, and satellite transmission.

Yet on American DTH satellites, DVB is used by one distributor and DSS by another.

Sources?

http://www.ebu.ch/en/technical/trev/trev_295-huang .pdf

Where do people think that 10 billion comes from? It's a tax. A very sneaky one, but a tax nonetheless. You'll be paying extra for all the resulting new technology. Or, worse still, the technology won't arrive because the companies paid a ridiculous amount in the auction. We've seen something like that in the UK with mobile phone spectrum. See the first paragraph of this editorial.

So, please, don't talk about the switchover as if it produces money. It doesn't, it's just a tax that people aren't smart enough to complain about.

It's coming to Europe soon on Pay TV, there's a few HD feeds already about though, like Euro1080 on Astra 1 and various US networks come and go when trade fair's are on. There's also various tests, there's once coming up on Thursday by BBC/ProSieben on the Astra satellites. You can download a sample already.

TPS in France is going HD next year, Sky Digital in the UK are going HD 2006-07, Premiere in Germany are also announcing plans and I think Canal+ (inc Scandinavia) have something in the pipeline.

A consortium has just been set up to promote standisation in Europe, setting out minimum specs, the interconnects (HDMI) and issuing logos. Interestingly European kit also has to be able to scan at 720p60 and 1080i30 to be certified which are native HD resoutions in the US. There's various trials going on in the EBU setting out the desired format, it seems a progressive format is most disired because it matches the scanless native of modern displays (Plasma, LCD etc), so they're pushing 720p initially with the hope moving to 1080p by the time this is mainstream. The DVB group also has various developments in their newsletters.

The BBC are going to produce all their content in HD by 2010 and are already playing with their new toys

Too right. The BBC is currently leading development of TPEG - a travel information standard. This is a project of the EBU and free to use. The BBC are supporting TPEG over other travel information standards because there would be no requirement from the receiver owner or manufacturer to support or purchase proprietory mapping or co-ordinate data.

Details on TPEG are availabe here.

Too right. The BBC is currently leading development of TPEG - a travel information standard. This is a project of the EBU and free to use. The BBC are supporting TPEG over other travel information standards because there would be no requirement from the receiver owner or manufacturer to support or purchase proprietory mapping or co-ordinate data.

Details on TPEG are availabe here.

Betamax was better!
1) It had stereo sound a long time before VHS
2) Betamax always remained in the professional part of the market.
3) Not only was it the best system, it still iss. Digital Betamax is the preferred portable choice of EBU, just in front of DV
I find it hard to believe that someone could actually back up such a claim that VHS was better than Betamax in the beginning. The length of the tape isn't everything, at least not when there's such enormous difference in picture and sound quality as there were between Beta and VHS. According to people in the industry, VHS only caugth up with Beta when they released SuperVHS. And even that couldn't penetrate the professional market.
As for the pr0n comment, probably true! :)