Friday, December 30, 2005

Some pictures from Christmas



These are all from my telephone - for pics taken on a proper camera the link is to our photo blog.

Tuesday, December 20, 2005

Happy Christmas to you!

I'm off on my Christmas break - hurray, what a busy year it's been - I have lost count of all the installs we've done this year. I'll be glad to get home tonight (a few friends coming over) and know that when 2006 comes around we have a load of new challenges - the year has pretty much finished with all the jobs done.
If you want to see our family Christmas newsletter see here.
Oh, the link above is to the Podsafe For Peace record which has a great back-story (courtesy of the Daily Source Code - see the link in the Podcast section, right). The song is cheesy as a big omelet but I love it!

Causes of colour

While I'm in a colourimetry mood I thought I'd put in a link to this site that is a really nice overview of the physics of colour - I couldn't remember the type of scattering that occurs to make things appear blue - it is of course Mie-scattering - see it all here.

Monday, December 19, 2005

"The perils of colour-space conversion" - an article for the Root6 Dr. Watson newsletter

At work we produce a newsletter which I sometimes do a technical piece for - so forgive the slightly client facing tone of this piece!

An important aspect of the production/post-production chain is maintaining correct colourimetry. If the director of photography or the lighting-cameraman want that certain shade of red to be correctly delivered to the viewer then attention needs to be paid to the correct representation from the camera (be it standard or high definition or even film) through all transfer operations (potentially going between resolutions, YUV/RGB colour spaces and bit depths) to the final display surface (be it a CRT, LCD or even cinema screen). In truth colour-space management for film is a complex issue best handled by specialists like Filmlight (who are represented in the UK by Root6) and is perhaps beyond the scope of some technical notes in a newsletter! That said there are many points worth making if you are acquiring or delivering for high definition television and worried about going between colour spaces.

The CIE Chromaticity diagram (first published in 1931!) shows the gamut of human vision – essentially any display surface is a subset of this diagram and will be a triangle with red, green and blue apexes and white (actually monochrome – as the luminance of the image is reduced it tends through grey to black) in the centre. In the case of “illuminant D” (AKA “D6500” or “EBU phosphors”) – the standard definition colour standard used since the sixties in Europe we enjoy a slightly wider red range than our colonial cousins but every gamut (television, film or print) is a poor compromise on what your eyes can handle. This is where the problem begins – you have a very critical instrument at your disposal to see these differences.

Part of the problem is that all of our machines acquire images in the RGB space (TV cameras, Telecines, graphics workstations etc.) but for the most part we post-produce in a YUV space (with the exception of Sony’s new HDCam SR format, an RGB high-definition VTR) which represents an immediate lowering of the colour space. This has been the case for a long time and is well understood. Manufacturers have agreed a common “matrix” for transcoding. To make the luminance portion of the component signal the following is used:

y = 0.299 * r + 0.587 * g + 0.114 * b

Well, this is the case for standard definition (AKA “601”), but for high-def (AKA “709”):

y = 0.213 * r + 0.715 * g + 0.072 * b

Which, even if you’re not so into the maths, will give different values for the luminance (the overall level and hence look of the picture). This makes it doubly important that you get your cameraman to record some colour bars at the head of each rushes tape and that your editor checks alignment on his scope before he starts adding captions etc. The best of breed digital picture instruments are from Tektronics who Root6 are pleased to represent.

If you find you have a colour space issue (particularly going between standard and high definition formats) then the Belle Nuit Montage test chart is a good starting point. It can highlight all the common transcoding errors – be it the limited 8-bit range of old D1 videotape to some of the sub-sampling issues associated with HDCam. You can download the file at various resolutions from their website and by injecting it at the start of your workflow any inadequacies are quickly revealed and can be corrected.

Friday, December 16, 2005

DVS in Hannover

I've just got back from a training course in Germany with DVS - we sell for them in the UK and they have a great product range for standard and hi-def television as well as film DI workflows. We installed their SAN and two Clipsters at Midnight Transfer earlier this year. They present a very integrated solution if you are in the business of dealing with film dailies or grading and the Clipster is a solid "Swiss army knife" type gadget - it'll deal with every uncompressed image format used in film (typically DPX files) and every variation of video raster. I'd not used the editing and effects features before but really enjoyed three days of getting to grips with it and the v.2 software.


Stephan & Emanuelle from Post Logic, Chia from DVS (our trainer), myself and Ben (Root6) who enjoyed the fact that we got to hire a 5-series BMW!


We also got taken through the hardware of the Clipster from a maintenance point of view and spent the last day doing SAN configuration. Their SAN is based around ADIC's StoreNext file system and as such allows you to have clients using all the common OSes - Windows, Linux, Unix (variants as well as IRIX for SG) as well as OS-X Tiger. They use X24 raidheads to control the array and so the system is not burdened with RAID operations (unlike a Unity).



Hannover is a nice city - we trawled around the Christmas market and saw the statues of the three Nanas by Niki de Saint Phalle - many thanks to Chia from DVS for entertaining us!

Wednesday, December 07, 2005

Colourise black and white images

This is a very cool little freeware app that allows you to just mark an image with a few colour swipes and it does a very creditable job of colouring it. Do you remember when SG workstations first allowed people to colour black & white video? Popular for three weeks in about 1985!
Anyhow - I thought an application for this (other than making Stan Laurell look unwell!) would be to give a new look to digital images that you'd previously made monochrome.

Tuesday, December 06, 2005

Engineering page at suitetv.com

I don't normally big up facilities' websites because they are often self-serving boast-fests! Read any of them from the one-man-and-his-dog boutiques to the big no-change-out-of-a-grand-an-hour "high-end" (sic!) companies and you'll believe they not only invented television but they also drive the entire production (as well as post) process.
...numerous awards for their work in commercials, short-form and broadcast programming, and their creativity is reflected in the company's impressive client base. No matter how complex your post production problem, you can be sure it will be....blah blah blah
You get the pictures.
Anyhow - The Suite (in Newman Street) have a really cute engineering page - just a bunch of pictures captured from the CCTV and looped in high speed - I was entranced - you see a guy fixing a VTR, them someone drinking tea, then someone installing something on a PC - it's great!

Monday, December 05, 2005

Yet another reason I could never own an iPod

For the numerous other reasons see here!

Saturday, December 03, 2005

If I got a tattoo.....

Yes indeed - if there is one thing that I wish the whole world would remember is that there are well defined relationships between analogue and digital audio levels. PLEASE - if you are (or have any influence with) a manufacturer of professional television equipment then align your A->D and D->A converters appropriately for your market, which is the case of Europe is -18dBfs for 0dBu.
I installed a new v7 Protools on Friday - wrong (set for -14dBfs), Avid still ship set for -20dBfs and countless other bits of kit come in at -24dBfs. Perhaps these people just don't understand (or can't be bothered!).

Friday, December 02, 2005

Leitch routers and inheriting old gear

One of the things that makes your heart sink when doing integration projects is when the client says "oh, can we re-use our existing routers?" - it makes sense (from their perspective at least!) but represents a lot of work. I worked 'till nearly midnight a couple of days ago getting an old (read late 90's vintage) Leitch XPlus router to talk to it's control panels. Leitch is probably my second choice for routers - my first is Quartz - they only do routers and they are a small English company - you can talk to the designer if you have an issue and their tech support guys are entirely focused on routers and their control systems. Their networking is good as well - you can do a configuration download from any attached device - even the control panels allows you to talk to the mainframe over the QLink network - it made a recent job at MTV a lot easier being able to do programming table changes by hooking my laptop up to the XY panel rather than having to shlep back to the machine room every time. I don't know Probel very well anymore - they were all over the Beeb - but that was back in the late eighties/early nineties and so I'm very out of date with Probel.
Anyhow - back to the Leitch - I could get the video level control panel to talk to the chasis and route but every time I attached an audio panel it wouldn't route both sides of the stereo pair - in the end I set the audio panel to issue commands on all levels bar the video and that did the trick. It's a bit of a bodge but works - until they try and attach an RS422 level (and then I'll get the call - probably at night!). I'm thankful I paid attention to the ESAM protocol when I was building Oasis's machine room - once you have a feel for how that works you can pretty much understand how any modern router's control system operates.

Back to inheriting old gear - monitors are the worst because the client expects them to look as good as the rest of the install - even with soft ten-year-old tubes they think the new setup will bring life back to those displays that should either be re-tubed or retired! A job we did earlier this year was a good example - the client had origional series 16x9 PVMs - even when new they weren't colour accurate but ten years down the track - well. Suffice to say Sony no longer make the SDi input board for that monitor and so we had to feed them analogue component (which in most instances is my prefered method - the analogue output of an Adrenaline BOB, for example, is a better picture than the 8-bit conversion done in the monitor input card) but the YUV was from a Decklink card! I'll stop now before my blood boils!

Friday, November 25, 2005

VideoReDo

I used to have an app that came with a Hauppage capture card called something like MPEG Razer (might have remembered that wrongly) which was ideal for chopping out ad breaks from TV shows captured on the PC. The application was keyed to the card and so once I upgraded to a DVB capture card (see here) I couldn't use it - it was such a good idea - letting you chop the MPEG stream only at I-frames, thus avoiding breaking the GOP structure and meaning you could re-save the cut very fast and no loss of quality from decompressing / re-compressing. Anyhow - I recently discovered VideoReDo which is superb. As well as super-fast MPEG editing it has a really good audio-sync tool which allows you to slip sync as the clip plays. The thumbnail and waveform display is very helpful for that and the real killer feature is that it can automatically detect ad breaks and mark them for removal (subject to your approval). If you really want to frame-accurately cut the GOP it only re-compresses the sequence back to the I-frames either side of the cut. Very clever. It also has tools for fixing non-compliant streams.

Guess what show I was cutting when I grabbed that screenshot!

Thursday, November 24, 2005

What the Dell's going on?!

I bought a new Dell inspired notebook on behalf of a friend and thought I'd better run it up and make sure all was well (including the driver for the very groovy Dell 922 scanner/printer) before I sent it over to her. You can't fault Dell For their machinery - well built, modestly stylish (it's a computer after all!) and with after-sales support second to none. The thing that really surprised me was how many bit of rubbish they pre-install. After the first boot (authenticating online etc.) I timed how long it took to power up and reach the desktop - 4 minutes 37 seconds! Once I'd removed the various 90-day try-out versions of EVERY Norton product (see here for what I think of their products!) and put a good anti-virus package on there it was booting in 46 seconds. Why do they bundle installers for all the worst ISPs as well - having AOL9 pre-loaded and in the startup seems like it should be almost illegal! Anyhow - it is a tidy little laptop.

This got me wondering about the larger relationship between software and hardware and I pondered back to twenty years ago when I was doing a degree in maths and programming. At the time object-orientated languages were thin on the ground (Smalltalk was the only one I had any exposure to) and so working with either a procedural language (C, Pascal, COBOL etc.) or a functional language (LISP, Prolog) the developer could see how the abstraction applied to the final assembled code. All the programmers I graduated with (for example) could also code in Z80 and x86 assembler - not too many programmers can do that today. There was even the idea of induction to prove code. This was an idea that came from defense contracting that allowed you to show that a routine (typically in LISP) was good for every case by showing it worked for the specific case of n=1 and then for the general n+1 case. You could have confidence that a subroutine or even a whole program would work properly every time. Shoot forward to a few years ago when I was still running engineering for Resolution and I had to commission a database application that would support a 24-7 reality TV show and the programmer refused to stand by what he wrote - there was no way he'd be on call-out to fix any bugs we discovered down the line. It seems that as software development has moved into the realms of bolting objects together the idea of robustness has gone (get a programmer to explain the idea of garbage collection and why it is necessary in modern languages).

This is well illustrated if you compare the state of the two biggest NLE applications in the late 90's - Avid and Lightworks.
  • Avid v.7, which if you used/installed/fixed it you'll know, was a capable application that needed a 300Mhz computer to run on a typically required 256megs of memory. It crashed often and took many minutes to boot. Judging by the multitude of error messages I got familiar with it was written in at least four languages and had components in it that hadn't been re-written in a decade (I know v.1 came out in 1991 but even today it has elements of EditDroid, the Lucas Film application that Avid acquired in the late 80's).
  • Lightworks v.6, by comparison was a stable product that crashed once a month (on average), booted in under thirty seconds (due in part to DTX - they wrote their own disk handler rather than rely on an off-the-shelf OS!) and had an incredibly modest hardware requirement - a 66Mhz '486 with 64megs of RAM! It also came on three floppies!
Having supported several Lightworks suites for three years I was horrified how bad Avid was when we got our first few at Oasis. I knew one of the guys at Lightworks and he told me that it was all written in C++ with some C and assembler for the time-critical bits.

Compare all this to how far hardware has come - back when I was doing that degree the 25Mhz '386 was the fastest cheap processor around and even then people were sounding the death-knell for the CISC architecture. The Von Neumann bottlekneck was perceived as a real problem for traditional processor design and RISC chips (especially the T800 series of transputers) were going to save IT. BUT, hardware design got better and all those problems haven't held back the Moore's Law express-train.

Tuesday, November 22, 2005

Tri Level Syncs

I get loads of people asking me about Tri-level syncs - they are becoming more significant in this HD-world and so here is a quick note - the link is a good explanation on the Extron website.
The thing to remember is that unlike HD-SDi video tri-syncs can be distributed much like normal black & burst - the same cables, jackfields, and even DAs and routers can be used to carry them. Equipment that uses tri-syncs will often need it's reference input switched (one day it's a 24P job, the next it's a 1080i (50 field) one) and so small composite routers and multi-o/p SPGs are a good idea.
The horizontal timing reference point for a standard bi-level sync signal is defined as the 50% point of the falling edge of the horizontal sync pulse. In order to ascertain this point precisely, it is necessary to clamp both black-level and sync-tip level and derive a value half way between. If the signal is in any way distorted, this will give H timing inaccuracy. With a relatively pedestrian standard def signal (line rate in the province of 15 Khz) this isn't such a big deal, but with 1080 lines per frame this becomes more significant and with a tri-level sync signal, the timing reference point is the rising edge of the sync signal as it passes through the black-level. This point is much easier to determine accurately, and can be implemented relatively easily. It is also more immune to signal distortion.

Monday, November 14, 2005

Sony's DRM "Root Kit" controversy

This one promises to run and run - if you've not been aware of it Sony/BMG have audio CDs out there with an autorun app that installs a media player onto your PC. Once installed it patches your Windows kernal (programmers refer to this as a "Root Kit") so that Sony/BMG CDs become unrippable by launching the Sony Media Player and taking control of the CD drive. The terrible part of it is that if you uninstall the media player you potentially loose your CD drives (at best) and at worst wind up with a machine that BSODs. It is unforgivable behaviour and if I found my Windows install was thus compromised I re-pave the machine with a new install of the OS. The lesson is to make sure you have auto-play turned off on all your removable drives.
Anyhow - a very funny post on Sysinternal (who broke the story origionally):
f you want a more concrete proof, try to rename your favourite ripping software as $sys$whatever.exe and then run it again. You'll notice that the DRM system can no longer detect it, and thus you'll get good copy of the track you try to rip instead of one filled with noise.

Thats just hilarious. I think everyone should simply not worry about removing the rootkit, as this is too difficult, and then just do at Matti says, and use the rootkit to make your favorite ripping tool immune to the DRM. On second thought, is their software breaking the DMCA? It provides a method to bypass copyright protection that they install? Hmm...
There is a worry that virus and other malware authors can exploit this loophole - but the idea that the very thing that Sony were trying to prevent now gets easier is funny.
A list of Sony/BMG disks that you should avoid.

23rd November update: It now appears that Sony had bundled the open source Lame encoder as part of the XCP install - in clear violation of the GNU public license. It seems it's OK for Sony BMG to install software on your PC that stops you from making legitimate use of the music you purchased and at the same time they're ripping off other people's IP!

You couldn't make it up!

Sunday, November 13, 2005

"He's running a bit rich"

Thanks to Simon - funniest video clip I've seen in ages - had the whole office laughing.

Thursday, November 10, 2005

Operation Christmas Child

Despite what you may have read in The Guardian from last year these guys do a tremendous thing every Christmas. More importantly they give normal people the chance to be involved in something special. A couple of years back a friend was a volunteer driver for them and worked in an orphanage in the Czech Republic in the run-up to Christmas. He was profoundly touched by the experience and couldn't even see where the cynical white middle-class liberal (with a small L!) press had got their info from. Still, if you've got nothing honorable in your own soul it's hard to recognize selflessness in others - you just assume they have ulterior motives.
There is an anti-American undercurrent in the newspapers aimed at the chattering classes and I don't like it. Every American I've met (here and in the States) has been an entirely reasonable person. Surely you can hold a view that you dissapprove of Bush and the war and yet still feel affectionate towards normal Americans.
Anyhow - it's not too late - the couple of hours it'll take you to fill a shoebox with some goodies (and maybe £10 out of your Christmas budget) will be time and cash better spent than you'll ever realise.

Wednesday, November 09, 2005

Mix tapes!

Saul put me on to this site that just has pictures of audio cassette stock. I remember my Dad making mix tapes (I'm sure the expression then was "compilation"!) for car journeys onto this type. This is great - a website that actually bought back some childhood memories very vividly.
Now where are those old eight-tracks?

Tuesday, November 08, 2005

Cerberus FTP server

I host several websites on my server under the stairs at home - running IIS (for my sins!) and came back to a bunch of emails moaning about not being able to update pages. I had a good look and although I seemed to have FTP access to IIS via the command line and via SmartFTP I couldn't get Contribute or Blogger to touch it - IIS would keep breaking the connection a few seconds after any transfer started.
It transpired that there was a hotfix over the weekend that "...addresses some compatibility issues with IIS and passive FTP transfers" - well, if the issue was it used to work then they have indeed addressed it with the now it doesn't solution! I suppose I could un-install IIS and re-install (not forgetting to disable auto-hotfix!) and spend half a day getting the configuration right but I tried Cerberus (Rupert mentioned it yesterday) and was amazed - installed and configured in twenty minutes and all my users are happy again. Yet another one of those cases of grasping the nettle and realising how easy it is to break away from Microsoft and how much better things seem to work afterwards.

Monday, November 07, 2005

Virtual desktop PPMs

Paul Marshall is a very clever chap - he often posts on uk.tech.broadcast (Google Groups link in menu bar, right hand side). Here are a few stand-alone audio meter apps that just look at the o/p level on the system sound card - you tell it what zero level is (typ. -18dBfs for TV work) and it makes an animated meter (VU, Digital, BBC PPM) that has all the ballistics of the real thing. I've had his dual-PPMs up on screen all day for spoken as well as music content and they are the business!


11th Nov Update - Rupert has got this working with ExpressPro - very neat. In Settings you need to tell the audio tool to use the system mixer - select "mix" or "wave mix" in your Windows mixer tool record setting and you'll be off to the races!

Friday, November 04, 2005

Audiophile at I-Like-Jam

This is an hilarious bunch of links to unnecessary audio accessories - $1,500 for a mains lead? $30,000 for interconnects! A fool and his money are easily parted it seems.
The Intelligent Chip is a one inch square, bright orange plastic wafer that, when placed on top of a compact disc player for 2-3 seconds, upgrades the disc (CD, DVD or SACD) being played at the time. The sound of the upgraded disc has more detail and articulation, better dynamics and an absence of "digital harshness." Voices are more human-sounding and less synthetic. The upgrade is permanent. Inside the white translucent Intelligent Chip case are two ultrathin, clear polycarbonate sheets, one on each side of the Chip. The manufacturer's product brochure states, "The Intelligent Chip should be put back into the packing case after using, because the packing case can protect the quantum material of the Intelligent Chip, preventing them from leaking."
The nonesense goes on with reference to Schrodinger's cat and other quantum ideas, the summary is the best;
The Intelligent Chip works via coherent quantum superposition and quantum entanglement, in which two coherent light sources - the CD laser and the quantum dot laser in the chip - interact strongly with the atoms and molecules in the CD's polycarbonate layer to produce long-lasting, superior transparency for better optical signal to noise ratio (SNR). Laser light escapes the player via a number of small holes and gaps in the player case. The emitted light from the quantum dot laser instantly comingles with the CD laser light in the room and inside the player.
Now what has escaped these people's attention is that with some CD players you can get the CD to show the number of errors in the bitstream (the Red Book standard specifies Miller Coding so errors are easy to spot). I used to have a Sony machine in the early nineties that had a maintenance mode that would make the display show the error count rather than track number etc. I had several disks that could play end to end with no errors - so, how can improving the s/n of the bitstream signal improve the final analogue sound if the digital signal wasn't noisey enough to give errors in the first place?!
However - the $1,500 power cord really got my goat! I wrote an email to the dude;
Hi,

I just read your review of this power cable - did you write this for a joke or is it a paid-for "advertorial" for the company concerned?

If this power cable produced a measurable difference in sound reproduction why didn't you include some measurements (Total Harmonic Distortion, bandwidth figures, signal-to-noise etc.)? - Would you know how to measure these things?

"...like most other AC products, it will undergo changes in sound for three to five days after its application to a component. Judging the absolute merits of any AC product within this "settling period" will most often prove misleading. "

What, precisely, happens to a power cord during this "bedding in" period? For such a high sum you'd expect the manufacturer to burn the cable in for you!

What, in your view, makes this a good power cord? What was the impedance per metre? What about the capacitance? Do they make a different design for 50hz users? If it is so optimised the difference between 50 and 60Hz is surely significant.

Surely improvements and order of magnitude more significant than this could be achieved by hard-wiring the amp's mains input to the incoming mains feed from the street - even then they have merely used copper cabling for the mile back to the substation.

Regards,

Phil Crawley,
I'll let you know what comes back!
I really feel it's important to stand up against this pseudo-science and trickery.