Archive for October, 2007
Kudos from the Blogosphere
Our Article on Linkbait Gets a Thumbs-Up
A regular reader and commentator on our blog, Gary R. Hess, recently gave us kudos for our January, 2007 post, “Leveraging Linkbait,” by Rand Fishkin of SEOmoz.
Writing in his blog, Gary called out “Leveraging Linkbait” as one of the 12 best articles on the subject of linkbaiting.
Never heard of […]
Polar Discovery
In less than a month, three teams of scientists from the Woods Hole Oceanographic Institution will ship off for “the bottom of the world”—Antarctica. From November 24 to December 23, the groups will sidle up to a dormant volcano, examine 300,000-year-old lava flows, scrutinize the health of the continent’s rocks, and get to know the life and times of two penguin colonies facing global warming.
This is the third of four treks to the Earth’s poles, Antarctica and the Arctic. If the past two expeditions are any measure, the media team accompanying the researchers will also do some heady stuff. The group behind Polar Discovery, the expedition’s website, has shown its prowess at crafting an especially rich online experience. Thanks to them, interested parties from around the globe will be able to follow the field researchers through live calls, daily photojournals, videos, and the occasional sport of “polar fun.”
Already, readers can read up on the splash tags that will be affixed to the Antarctic penguins, consider the “lidar” camera that will capture three-dimensional images of the rock faces, and read more about Antarctica, a place Encarta Encyclopedia describes as “the southernmost, coldest, windiest, highest, most remote, and most recently discovered continent.” That’s one serious list of accomplishments.
“We are storytellers,” the Polar Discovery Web maestros say, and they certainly know how to weave a great online tale. They’ve dedicated themselves to providing a true “inside look” at these field research efforts. That behind-the-scenes peek means “you will learn everything—not just the research team’s tools and findings, but also how they get to remote locations like the North Pole, how they stay warm when the mercury drops to -30F, and even what they eat for lunch.” PB&J?
Polar Discovery promises that “no one is going to get seasick” on this upcoming trek to the Antarctic. We’ll cheer to that—and we’ll be checking back to see if they’re right. Bon voyage, team!
Picks is getting a whole new look! Check it out at beta.picks.yahoo.com.
Emdashes
Fans of The New Yorker are a dedicated bunch. They relish its arrival every week, check the bylines, and then dive right into a 20,000 word piece. It’s no wonder this passion for a beloved magazine has spawned a site devoted to its pages past and present. Whip-smart writer Emily Gordon obsessively blogs about all topics great and small related to her favorite periodical. We were enthralled by discussions related to cartoons, literary giants, and nitpicky grammar. If you want to skim the highlights, we recommend checking out discussions with “The New Yorker” librarians, the always-debatable Pick of the Issue, and regular plunges into the history of the esteemed publication. Whether you’re a cover-to-cover obsessive or just a grazer passionate about ”Talk of the Town,” you’ll find Ms. Gordon has created a delicious companion to America’s best magazine.
Picks is getting a whole new look! Check it out at beta.picks.yahoo.com.
Happy Halloween
Happy Halloween from Pics of the Week ![]()
Jan 6, 2008: Lightsabers and Spitfires at The Republic Cultural Centre
The Anglo-Chinese School (Independent) Philharmonic Orchestra will kick-start the first Sunday of 2008 with ‘Lightsabers and Spitfires’, a performance of eclectic and exhilarating music at The Republic Cultural Centre.
Led by its Music Director and Resident Conductor Chan Tze Law, the Orchestra will perform orchestral spectaculars from the Star Wars Trilogy by John Williams, the Spitfire Prelude and Fugue by Sir William Walton, and George Gershwin’s Rhapsody in Blue, the latter with pianist and Anglo-Chinese School (Independent) alumnus Albert Lin. Albert Lin made his debut in the 2007 Singapore Piano Festival and is recognized as one of Singapore’s most adventurous concert artists of his generation. Joining the orchestra for this special event are members of the Singapore Armed Forces Music and Drama Company and the Singapore Armed Forces Central Band.
Comprising of students from both secondary and pre-university sections, the Anglo-Chinese School (Independent) Philharmonic Orchestra enjoys sustained collaborations with notable arts groups in Singapore and orchestras overseas. In 2007, it accompanied violinist Gabriel Ng, recipient of the 2006 HSBC Youth Excellence Award, at a Charity Concert at the Esplanade Concert Hall. Outside of Singapore, its members have performed with the Trinity College of Music London, the Mid-Sussex Youth Orchestra in the United Kingdom and the Western Australian Youth Orchestra. Since 1999, the Orchestra has achieved consecutive Gold awards at the biennial Singapore Youth Festival Central Judging, including two Gold with Honours awards (Secondary and College category) in 2007.
Tickets at $12 and $15 from www.gatecrash.com.sg. Hotline at 62225595, The Substation Box Offic, all SingPost Branches and S.A.M Kiosks.
Apr 16, 2008: Mobile Content World Asia 2008 at Grand Hyatt Singapore Hotel
Mobile content world asia 2008 singapore terrapinn April.
An Overview of Windows Sound and Music “Glitching” Issues
The following post comes from my colleague Steve Ball, Senior Program Manager for Sound in Windows Vista, and continues his team’s on-going series on how Windows Vista treats various forms of audio.
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Part I: Why does my Windows sound sometimes “glitch?”
Windows is a rich and complex OS designed for multi-tasking users whose tasks must share access to scarce system hardware and resources. Unfortunately, despite multiple decades of incredible advances in PC and CPU architectures, there are non-trivial, complex interactions between applications, processes, and devices in even the most advanced personal computers that make a supposedly “easy” task — like playing back music without occasional glitches — much more difficult than it may seem at first glance.
Another way of thinking about this: it seems odd that a modern >$2000 PC may sometimes have trouble seamlessly playing back music when $20 CD players can effortlessly playback music without glitches.
So why do many $2000 PCs occasionally glitch while playing back music? The quick answer is this: Windows is not a single-function device like a CD player.
A slightly longer answer goes like this: even an average Windows machine today is commonly used simultaneously as a media player, word processor, presentation projector, spreadsheet number cruncher, authoring tool, photo editor, media server, video recorder, music composition tool, communications device, search engine, virus detector, data compressor and decompressor, and backup manager. And these are only a few of the possible tasks and processes that are run at the same time on the hundreds of millions of Windows machines that are in use today. Each of these tasks or processes, in isolation, would hardly tax the resources of modern PC hardware. But in our multi-tasking world, unavoidable resource conflicts do sometimes occur between the huge and diverse ecosystem of Windows hardware that enables these tasks. Even on the most expensive, brand-new machine, occasional glitches can occur if and when the system attempts to divide its finite resources among these multiple, diverse, independent, power-hungry activities.
What is a glitch?
A glitch is a perceivable error, gap or pop in the sound caused by discontinuities in the audio signal during playback or recording which result from processing or timing problems. Glitches during music playback can sound like a loud “pop” or like a brief slice of silence randomly inserted where your music should have been. Some customers have also described what “glitching” in their own words as:
- audio stops a little bit
- breaks up
- choppy
- clicking
- corruption
- crackle/crackling/crackly
- interruption
- jitters
- jumpy
- skipping/skip/skips
For the purpose of this discussion, let’s lump all of these descriptions together under one general class of problems and call these “glitching.” While a glitch that happens during music playback can be annoying and unsettling, a glitch that occurs while you are recording or communicating with someone can result in frustrating and unacceptable data loss.
What causes my Windows sound and music to glitch?
Digital media processing is time-sensitive. Playback requires specific work to be performed by a given deadline — otherwise presentation or data loss can occur. A “glitch” occurs when a deadline for time-sensitive processing is missed or when time-sensitive data is lost.
For example, in Windows Vista, playing back music involves “work” that must be done at least every 10 milliseconds so that there can be a continuous stream of music out to your speakers. The “simple” task of playing back music consists of the following steps, all of which must be completed before a strict deadline:
- a small chunk of data from a music file needs to be read from a disc (CD or hard drive)
- this data needs to be “decompressed” or “decoded” (usually in system memory) so it can be streamed out to your speakers in a format that your sound hardware understands
- the decompressed sound data needs to be copied from system memory to your sound hardware memory
- the data in your sound hardware needs to be sent to your speakers at the appropriate time
- repeat steps 1-4 flawlessly every 10 milliseconds (ms)
In this example, if any of these steps aren’t completed on time, then the user could hear a glitch in the music playback.
Elliot Omiya, Architect on the Sound dev team, puts this 10ms cycle into perspective: “it’s just slightly longer than the time it takes a nerve impulse to travel from the end of your finger to your brain (~8ms), known as NCV (nerve conduction velocity). Because synapses are like network switches, there is switching time involved before the nerve impulse gets to the brain, i.e., switching time adds to latency.”
There is some good news in this story: Windows developers have made significant progress over the years in reducing glitching across key multimedia scenarios. For example, music playback on an otherwise “lightly loaded” system can be generally as smooth as that $20 CD player.
But because of the multi-tasking nature of Windows and the vast array of new and legacy hardware in the ~1B PCs that are used to playback music today, this allegedly simple process is made more complex by the resource sharing that occurs between applications and hardware. For example, it is not uncommon for certain older devices driver to occasionally “lock out” the CPU for 10-50ms, thereby causing obvious audio glitches. This is just one example of the kinds of complex hardware, driver, and OS interactions that can cause glitches.
In summary, some of the common sources of glitches today include:
- CPU starvation
- GPU starvation
- Resource contention from devices and drivers (sometimes called “IO contention”)
- Network devices
- And, of course … bugs in applications, OS, drivers and/or hardware
My colleague on the Windows Sound team, Larry Osterman, also pointed out to me recently that humans are actually “hard-wired” to be disturbed by audio glitches. In an exchange about this topic, Larry observed that audio glitches are more obvious than video glitches because the ear’s tuned to notice high frequency transients — his visceral example of this idea is an image of a stick snapping in the woods behind you as an audio event that wakes you up before a bear wanders into your path.
In my second post on this topic, I’ll go a bit deeper in sharing details of work we’ve done in Windows Vista to address some of the known sources of potential sound glitches, including some additional background about a recent discovery of an apparent connection between multimedia playback and network throughput.
I wish to acknowledge the contributions and suggestions from my colleagues Hakon Strande, Richard Fricks, Alex Ferreira, Lan Ye, Larry Osterman and Elliot Omiya for this series of posts.
