Saturday, August 27, 2011

Sony BVM-E250 OLED broadcast monitor

I had an hour or so to set up a new Sony OLED grade-1 next to a Vutrix HD Pro-24 (their grade-1 LCD display which I like) - the Sony is twice as expensive as the Vutrix (£20k vs £10k). OLED as a technology is supposed to have a number of advantages over thin film transistor (TFT - the important bit of an LCD display. A few are;
  • In a TFT layer the polarisation of light is twisted through 90 degrees to allow the pixel to be illuminated by the virtue of the fact that the front filter is 90 degrees offset from the rear. In effect the transistor stops the light from the fluorescent (or nowadays LED) source. Since the light source is a few millimeters behind the pixel there are chromatic distortions inherent and since thin-film transistors don't shut-off all the light when turned off there are black-level issues. These are the two best known problems with LCD monitors in film & TV grading.
  • Thin-film transistors have a limit to how quickly they can be cycled - typ. 16ms at best (I know some manufacturers claim faster but it's smoke & mirrors). OLEDs can be cycled a lot quicker for better response.
  • In a TFT display the place where the colour is made (the three sub-pixel RGB transistors) is physically separate from the light source - not so with OLEDs where the illuminating LED is also the colour-maker.
So - with deeper blacks and fewer chromatic problems you'd think OLEDs were the way forward. The only thing to consider is the life-span. The blue OLED elements have an estimated life of 10k hours (around a third of the backlight of an LCD). Also - the metameristic character of OLEDs is different and so colour-management tools will need to be upgraded (I just spent £7k on a new LCD photometer!).

I thought out of the box the pictures on the BVM were very good - close to the VuTrix I'd just calibrated to illuminant-D (6504K at 80Cd/m2 for peak white). Response seemed as good with much better blacks, particularly from different angles. The monitor's de-interlacer didn't seem as good as I'd have expected for video-shot material but camera pans etc looked better than the VuTrix.

Overall I was impressed, but not an extra £10k impressed!

Friday, August 26, 2011

UPNP has always been a bad idea!

UPNP is a protocol that allows an application to open up ports on a router so that incoming packets from the Internet get to the correct IP address on the LAN. It's typically used to allow the XBox360 to set up open ports through your router to allow multi-player gaming. If both XBoxes are behind NAT routers there is no way that unsolicited traffic from one can make it to the other (hey, I never wanted your bullets to hit me!). Skype suffers thus if both callers are behind NAT routers (i.e. in most cases; who has an internet-facing IP address on their machine nowadays?) - details here). More recent versions of Skype will make use of UPNP if it's on the router.
You won't be surprised to learn that it's a Microsoft technology and I've always encouraged people to disable it on their routers. Any piece of malware inside your network can open ports and invite any other nasties in. In the case of XBox there are about four ports you need to open up for the Live! service to work. Anyhow - it turns out that Linksys routers have a bug that allows UPNP activation on the WAN side - that's right, with the correctly formatted packets you can open ports through a Linksys router from the Internet. Using something like UPNP Port Mapper will allow you to scan Internet IP addresses and open ports on those routers.

The title link is to the article on The H.

Thursday, August 25, 2011

Flame ain't all that

The facility that I'm building at the moment has a couple of Flame Premium suites - the very best version of Autodesk's TV and film compositing and finishing tool. Now I know very little about Autodesk products - I've never really worked in facilities where they were used. Flame, Smoke and the rest of them have been around for nearly twenty years and so you'd think they are what software people would describe as "mature products".
Anyway - a currently model Flame runs on an HP Z800 workstation with a Kona K3 card for video i/o (more about that in a minute!), an nVidia 4500 for desktop and their own proprietary fibre attached storage called "stone". They can typically handle two streams of 2k in realtime.
All very good, but everything is specified in a system - even down to the Eizo monitor you can use for the desktop display. This is because the SDi output for preview (which is not the output of the K3) is made by looping the 2nd DVI output of the graphics card into a daughter card that converts it to SDi. Consequentially you often see bits of the GUI on the HD video monitor. Now the reason for them specifying a certain model of GUI monitor becomes evident - they have to run the output at a rate near video for the DVI output to be convertible! This gets even more silly when you find out you have to use their own provided long DisplayPort cable to run it. We'd run in LC loose-tube fibre with DVI extenders which initially only worked whilst Linux was booting in text mode (i.e. before the X11 display subsystem could run). I had to throw in a Lindy EDID manager to fool Linux into thinking it really had the Eizo directly connected before we could run the desktop (and hence the Flame application).
This, along with a ton of little bits that the kit ships with; an 8-port ethernet hub, Lucid AES->analogue converters etc gives the impression they expect you to install the system on your dining room table rather than in a pro video facility. It really has the feel of a v.7 Avid from 1996! Cobbled together from third-party bits and only just running (everything on the hairy edge).
It reminds me of the Abekas DVEous (again, 1996) - one of the design engineers confided in me that if every bit of silicon on the video-processing board only performed to published spec then the system couldn't work. They relied on everything outperforming itself.

Thursday, August 18, 2011

Mute the TV automatically!

I've been a fan of ComSkip (a PVR plugin that automatically detects/removes TV adverts from recorded MPEG2 transport streams) and I firmly believe that technology will allow us to 'tame' various media sources - advert blocking in Firefox makes the web a nicer place, for example. Anyway - this is great, what a project;


Wednesday, August 17, 2011

iPhone 4 battery fault? NO!

Yesterday my iPhone 4 starting showing all the signs of a failed battery - the back of the 'phone was hot and it could hold a charge for around three hours. Darn - replacement handset with all the attendant messing around (although it a lot easier than it ever was on Windows Mobile!).
Anyhow - Googling around brought up a few sites with folks suggesting the mail daemon can get stuck trying to synchronise with Exchange and merely turning off push and letting the 'phone entirely discharge (or doing the hard-reset method of holding down the home and power buttons until the 'phone has powered off and restarted) and then re-enabling push sorts it.

settings>mail,contacts,calendar>fetch new data>advanced

By jove - it did the job. I can only assume the handset burns through the battery by keeping a data connection open continually.


I haven't blogged much recently because I've been on holiday. Pics here