It's taking the world by storm! Motorhome Racing! :-)
Nov 22, 2008
Nov 21, 2008
Video Codecs Explained (Gizmodo)
This is such a good article, I'm blatantly posting the meat of it here. Kornfused by the multitude of video formats? DVD VCD, Blu-Ray, VHD, SVHS, SVCD, AVI, MP4, Quicktime, WMV, etc:?
Video Standard Standards
• H.261 is not a term you have to worry about, but it's the technology that most video standards and codecs were originally based on. Originating in 1990, it's the first major digital video compression standard, and like other "H" standards, it was developed by the International Telecommunication Union. This one was primarily for teleconferencing over ISDN lines, and as such, it looks like it (bad).
• MPEG-1 Part 2 is another oldie, developed by the Movie Picture Experts Group and approved in 1991. (BTW, the whole "part" thing is because video is just one "part" of each MPEG standard.) Based quite a bit on H.261, MPEG-1 was designed to take VHS quality video and squeeze it down to a bit rate of about 1.5Mbps, optimized for CD transfers. No surprise, it's the standard used for all VCDs (which can play in most DVD players), still looks bad.
• With MPEG-2 Part 2, approved in 1994, we're finally talking decent vid. Also known as H.262, since it was developed jointly by the ITU-T and ISO, MPEG-2 is an extension of MPEG-1 that delivers better resolution and higher bit rates (3-15Mbps for standard def and 15-30Mbps for HD). It's the video codec used by DVD and digital television, though now it's slowly being replaced by the more efficient MPEG-4, except on DVDs, where it'll ride out that disc format's lifetime.
• H.263 is designed for sending video over poor connections. So it's used to encode most Flash video and to send video over mobile networks.
• MPEG-4 is where we really stand right now. It has a much broader scope than past MPEG standards, aiming to tackle both the low end (cellphones on a slow network) and the high end (Blu-ray). It's still developing, so it's not-so-coincidentally where this whole story gets messier. There are two relevant parts of the MPEG-4 standard for our myopic video purposes: Part 2 and Part 10—which is also known as H.264 or Advanced Video Coding (AVC). To be clear though, even though they're both part of the MPEG-4 standard, they're totally different formats. Nevertheless, both are more efficient at compression than past MPEG codecs, delivering better quality using less space.
• Okay, so if you've ever frequented a Torrent site, you've actually watched tons of videos that use MPEG-4 Part 2, though it's not like they would've had a flashing sign telling you so. MPEG-4 Part 2 actually has different "profiles"—the two that matter being Simple Profile, for low bitrate, low-res stuff, and Advanced Simple Profile. The latter profile is what's used by movies you would download in formats like DivX or XviD or 3ivx—which are all codecs that are essentially just differing implementations of the MPEG-4 Part 2 standard.
• MPEG-4 Part 10, the other part, was actually co-devopled by MPEG and the ITU-T, so it's also known—in fact, more commonly known—as H.264. It's more efficient than MPEG-2 and MPEG-4 Part 2, delivering the same quality video in as little as half the space, making it suitable for the low and high-end. Because of this, it's quickly becoming the standardest standard. It's part of the HD DVD and Blu-ray spec, replacing MPEG-2 in digital TV (like with satellite services and AT&T's U-Verse IPTV) and supported by pretty much every portable video player on the planet from the iPod to the PSP. Apple has a decent, if Kool-Aid flavored, FAQ about H.264.
• VC-1 is essentially a Microsoft developed alternative video codec to H.264 released as a standard by the Society of Motion Picture and Television Engineers, though it descends from the same H.26X/MPEG family. (It essentially started life as WMV9, but then Microsoft shopped it to the SMPTE to make it an industry standard, and now it is.) It too, is part of the mandatory Blu-ray and HD DVD spec, and is the official video codec of the Xbox 360. It's pitch is the same as H.264's—trying to deliver better quality using less space, like HD video in 6-8Mbps.
Free-Floating Codecs
Okay, so all that stuff up there are industry-wide standard video codecs. On top of all of those, various entities love putting out their own spin on those standards. As we mentioned before, DivX (proprietary) and XviD (open source), for instance, use MPEG-4 Part 2 (more specifically, MPEG-4 ASP) compression, meaning stuff that'll natively play back MPEG-4 ASP will also play back DivX. Like the Xbox 360, for instance. There are a ton of MPEG-4 ASP-based codecs, actually, like FFmpeg, 3ivx and others, but DivX and XviD are the most common. Same deal with H.264: Some well known codecs that use it are Apple's Quicktime H.264, x264 and Nero Digital. You've also got Windows Media Video (WMV) codecs, which are Microsoft's proprietary twists on industry standards.
Containers aka Wrappers
Alright, well you've probably noticed that none of your video files have the extension .h264 or .vc1 or the like. That's because videos are packaged in containers or wrappers that stuff things like the audio, navigational info, etc. along with the video in a single pretty file. Naturally, there are about as many of them as there are codecs. To be clear, you would take a video encoded with, say, H.264, and wrap it up as a .mp4 or .avi file.The majors ones are:
• AVI (Audio Video Interleave) is Windows' standard multimedia container
• MPEG-4 Part 14 (known to you as .mp4) is the standardized container for MPEG-4
• FLV (Flash Video) is the format used to deliver MPEG video through Flash Player
• MOV is Apple's QuickTime container format
• OGG, OGM and OGV are open-standard containers
• MKV (Mastroska) is another open-specification container that you've seen if you've ever downloaded anime
• VOB means DVD Video Object. Guess what? It's DVD's standard container, and what you get when you rip a DVD.
• ASF is a Microsoft format designed for WMV and WMA—files can end in .wmv or .asf
So, in order to play a video file, your setup has to be able to handle both the actual video codec and the container. It's why you can try to play an AVI file and Windows Media Player laughs at you, even though it totally played one a minute ago— the container was no problem, but it didn't have the right codec. Or conversely, even though an iPod could play back an H.264 encoded video, if it was wrapped up in MKV, it won't be able to read it.
Nov 19, 2008
This is one 'creepy' piggy bank... om nom nom nom!
Those wacky Japanese! If you want it, you can order one here!
Nov 18, 2008
Intel's i7 "Nehalem" release event Nov. 17th 2008
With all the bad news about Cali. fires, the tanking economy and such.. here is some good news for us tech-heads, who seem to spend much of our working hours sitting in front of, using, or *waiting* on a computer. It's been on the drawing boards for several years now as many of us that work as suppliers have known. But these are the sorts of things you dont really talk about in your day to day blogging, discussions etc: (nda's and all) if you want to remain gainfully employed :-)
It's also not really a secret that Intel uses software from Synopsys to help design and verify these sorts of ICs.
When will this sucker show up in a Mac Pro Tower system? Jan. @ MacWorld would be my guess? although those machines already have some pretty fast Xeon chips in them.
The guys/gals at ARS technica have the breakdown here:
The Microarchitecture
The Core i7
The making of the i7
Turbo Boost Technology
Power Gating Technology.. while not new, it's adding a whole level of complexity to processor design
5 Year design cycle
Az Wado Karate!
Belt test results were last night for the boys. Jaden added another stripe to his yellow belt and Jared moved up in rank to a blue belt!
Jared Schneider - Kata
Race Zladik - Kata
Dojo Slideshow
Does a Chinese Pirate say Arrrrgh? or Alllllgh?
Blu-Ray bootlegs.. it was only a matter of time!
As noted in this WSJ story.. pirated Blu-Ray discs are showing up in China.
Law enforcement in Shenzhen, China, raided a warehouse last month that contained HD copies of a number of popular movies. Over 800 discs in fake boxes, and holograms to make them look legit. The Chinese Blu-ray knock-offs run as little as $7 apiece (compared to the typical Blu-ray disc at $30+).
The process involves ripping high-def movies (cracking Blu-ray's AACS and BD+ encryption in the process) and re-encoding them using AVCHD, which offers a 720p picture. 
Because of the reduction in resolution, files can be burned to regular DVDs instead of the more costly Blu-ray discs, can you say profit!?.
Interesting, the BD+ encryption scheme has only been out a little more than a year and a half. BD+ is the DRM protocol used to protect Blu-ray discs. It makes use of a small virtual machine environment to enforce compliance. BD+ was considered much harder to crack than the encryption used on HD DVD discs.
Some crafty programmers at work here. Wont bore you with the technical details, but if you're a code/hardware person you'll find the comments in the Slashdot URL thread an interesting read!
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