And few things illustrate that more than the continuing confusion created by the various aspect ratios that video can be displayed in these days.

SD, HD, 4:3, 16:9, letterbox, anamorphic, wide-screen . . . all terms that you hear mixed together.

My good buddy and tech guru Chris Vazquez wrote an excellent article on this site two years ago about SD anamorphic , and it continues to be one of the most-read articles on my website, but questions still abound, especially when it comes to DVD authoring.

So let’s try to further clarify.

Some review:

4:3 means standard old-standard television viewing.

16:9 is wide screen.

SD is standard definition and is natively 4:3

HD is high definition and is natively 16:9

Now, let’s proceed, and feel free to read this slowly.  (Hey, I have to do that still with this topic, and I work with it every day!)

What options do you have if you are editing in HD 16:9 and want to lay out the finished sequence on to a SD tape, that is limited by its nature to automatically being 4:3? (e.g. BetacamSP or Digital Betacam)

You cannot maintain the HD quality of the signal, but you can keep the option open to be able to playback the video from the SD tape, in full 16:9 on a wide screen monitor.

That’s what anamorphic downconversion does.  Go back and check out the figures in Chris’ blog post.  It effect, anamorphic “squeezes in from both sides,” the 16:9 picture, like an accordion, to fit in to a 4:3 frame.

So when talking with you salesperson, you want to be sure you clearly discuss anamorphic options.

This is especially true when you are making an authored DVD project that involves using both SD and HD sources.

Let’s say you want to make a demo reel highlighting various categories, and you want to include a number of videos, some HD and some SD, in each category.  The authoring specialist needs to establish each category to playback one way, either 4:3 or 16:9 anamorphic.  (Remember, standard DVDs are automatically SD, not HD.)

Let’s say you had three HDCAM sources, two 4:3 digibeta sources, and one letterboxed Betacam source.

Well, if the category sequence is set up to playback anamorphic for wide-screen dislay, then the HDCAM clips will indeed play back in full 16:9, the two 4:3 clips will play back 4:3 in the center of the wide screen with black pillars on each side, and the 4:3 letterboxed source will play letterboxed inside a 16:9 screen, with black not only on the left and right, but also above and below.

Ugh.  that latter playback is probably not ideal.  The solution might be to see if an original HD version or a SD ananmorphic version of that clips exists.  If not, well, an aesthetic judgement needs to be made.

So taking a step back, there’s a corollary point to be made.  When transferring HD programs to SD tapes and DVDs at the end of a project, rather than doing so as a fiexed letterboxed version, you might want to strongly consider transferring those as anamorphic.  That way, as you can see above, you preserve your choices for later usage.

OK, let’s face it.  This matter will eventually become moot in the future as we gravitate toward using 16:9 HD exclusively.   But we remain in the midst of great transition.   And as long as we utilize SD footage and its inherent 4:3 aspect ratio, we will have to deal with this.

But never fear, count on me and my Video Labs sales and production colleagues to help you navigate through this.  That’s what we’re here for.

Contact me at dcryan7@videolabs.net or 240-268-3504.

And follow me on Twitter for more media news & info and special discounts.

If you found this article of interest, you may be interested in my quick-read blog post about our Blu-ray duplication capabilities.

Our videotape services department is still busy all the time. 

So this is a reminder that when sending us or anyone a source or master video tape, it’s just good practice to be in the habit of setting any record tab to “safe” so as to prevent any accidental recording over.

(Sure, we’re professionals, but hey, why take any chances with your media.) 

Such “record inhibit” tabs vary between tape formats.  On most broadcast formats like BetacamSP, dBeta and HDCAM, it’s a red tab on the underside that gets pushed in. (see photo above) . . .

And on other formats, like DVcam or DVCpro, it can be a slide button:

And hey, don’t forget those old vhs tapes you have at home with your priceless family memories.

Just break off the little tab (see photo at left) to prevent accidental erasure of those.

But there is at least one archive format that is different.  It’s the Hi8 video format that was popular in the 1990′s.  Sure enough, the tabs on those tapes have to be slid closed, resulting in the red tab being exposed, in order to be made “safe.”  (see photo below)

As my sales colleague Dave Tierney dtierney@videolabs.net said, “Just another reason why that format was a flop.”  Yeah, what was Sony thinking? 

Oh well . . . regardless of the format, we got you covered here at VideoLabs  www.VideoLabs.net  Contact us for all of your media replication and related multimedia needs.

My info is dryan@videolabs.net,  and I now have a new direct phone line: 240-268-3504  

I invite you to browse these categories of other related quick-read tape-related blogs on this site: 

video production: http://tinyurl.com/ygmmrzt  

video duplication: http://tinyurl.com/ylskb8e 

post-production: http://tinyurl.com/yzwltx2

And follow me on Twitter for exclusive short-term steep discounts: www.Twitter.com/DRMediaSolution

I always welcome your comments.

Recuerda que hablo espanol tambien.

Or perhaps you have played in a rock band, you’ve realized first hand the value of a good drummer.

Or maybe you’ve worked on your car.  You are likely well aware of the importance of the timing belt.

In any of those cases,  if you lose the “sync,” things start falling apart.

Same in video . . .

Ever been in an edit session and have a transition effect between two images jump around or change color?

Or perhaps you have you experienced the frustration of trying to make a dub from one source to another but the picture keeps rolling?

Or how about trying to output a show from a Final Cut Pro or Avid session and you can’t make a proper edit to start the layback?

What is likely happening in those situations is a lack of sync between the devices involved.

As you probably know, NTSC video signal typically runs at 30 frames a second. (ok, it actually 29.97, but let’s keep this simple for now.)  But just because two signals run at the same steady frame rate doesn’t mean that they can mix smoothly together.

My good friend and engineering expert Chris Vazquez likens it to one of those 4 x 400 meter sprint races one sees on the Olympics.  Runners have to be “in sync” for the handoff to go smoothly.

So likewise, to have a smooth transition between two or more video devices, such as in a dissolve between two cameras covering a live event, with a character generator added on top, the signals of each device have to be on the same clock.  In other words, they are “genlocked.” http://en.wikipedia.org/wiki/Genlock

What is commonly used for video reference in professional setups is an external sync generator.  It is set to put out a black signal that feeds to all the devices in the facility or particular setup.  That black signal, often referred to as ”house reference” becomes the master drummer. (further good info on this subject: http://tinyurl.com/yz9n8pp)

These range from the large sync generators for a facility

to the rack size for a small production company:

to a small one for an edit suite or field setup:

As explained in this well-written web article http://tinyurl.com/ykgcu8m “Genlock performs four main functions: vertical, horizontal, frame, and color synchronization. These features are all normal parts of a standard composite video signal, which allows a TV or monitor to display an image properly.”

Now you might be thinking that you know of situations where there was no reference put into a record tape machine.

And you would be correct.  Some higher end devices do have internal sync generators, and if that is not the case, most devices will adjust to the sync of the incoming video signal if nothing else is available.  But these are not ideal remedies since that type of sync is certainly not “system wide.”

There are devices that have “frame sync generators,” devices that act like a drill sargeant that force all incoming signals, no matter what clock they are on, to get forcibly reconstituted to a particular clock.  That may sound ideal, but there are disadvantages to the use of such devices, one being the possible introduction of a delay to a signal.

Still, frame syncs are popular in switchers used in remote live situations (like the battlefield or a remote location) where having problems with sync is just not an acceptable situation.

But returning to the main point, most professional video setups and facilities will utilize a black burst sync generator as their house reference.

Ah, but you are thinking, what about SD and HD?

Good question.  Yes, even though both are on 30 fps, remember from above that there are elements other than time that need to be kept in sync, such as color.  The SD signal and HD signal carry color information differently.  And since high end HD decks often provide internal downconversion (HD to SD) or upconversion (SD to HD) features, you’ll understand why on such machines there are usually inputs for both SD and HD sync.

I welcome your comments below.

If you enjoyed this article, you may want to check out some of the perenially-popular tech articles written by Chris Vazquez for this site, like, “Is the Generation Loss In Digital Betacam?” http://tinyurl.com/6yd6gn

Contact me, David Ryan, for your media replication and related multimedia needs.  301-217-0000 x104 or dryan@videolabs.net I follow Thomas Friedman’s “world is flat” model http://tinyurl.com/yhxfrkt, and I work with clients worldwide.  I would enjoy having the opportunity to be of service to you.

See what clients say: http://tinyurl.com/44uw9j

Follow me on Twitter for exclusive short term discounts and other items: www.Twitter.com/DRMediasolution

But have you hear about “audio description,” or the acronym, DVI? 

It stands for “Descriptive Video Information.” (Note: Some call it “audio description,” others “video description.”  WGBH, the PBS station in Boston calls in it DVS, a term they copyrighted through their Media Access Group  http://tinyurl.com/kmtuuj, the entity that pioneered the process.

However it is called, the purpose of the service is to make television and video programming more accessible to the visually-impaired segment of the audience.

(Data from the National Health Interview Survey states that over 20 million US adults have some form of vision loss even with glasses or contact lenses.)

Here’s how audio description works in short: On a separate audio feed of the program, a visually-impaired viewer can receive a specially-produced audio track of the program that includes additional narration describing any significant on-screen action and/or information that the regular audio track alone would not convey.

There are a couple of different symbols in use to signify that a program has DVI.  Some of them copyrighted.  The TV listings sometimes use a “D” to indicate audio description.  The most common one says “AD” in a box with little air waves.  (see logo at top of article)

In broadcast, cable and satellite, the DVI information is accessible via the SAP (Secondary Audio Programming) channel. http://tinyurl.com/l3d2ty

That is sometimes misnamed Spanish Audio Programming because often it is used to carry Spanish narration to English programs. 

In other media, DVI can be presented on a separate audio track.

As you might expect, there are only a handful of producers of DVI services.  One is the National Captioning Institute http://www.ncicap.org/.  A long-time contact of mine, captioning & audio description expert Anthony DeMarco, is on their sales and marketing team.

In some ways, DVI seems like alchemy to me because the audio description track cannot be longer than the existing audio track.  I mean, aren’t there instances where the audio track is already tightly packed with information? 

I asked Anthony that question.  He answered, “There are several ways to handle this. If the audio track is indeed tightly packed with information, the description for that section may already be done for us. If there is nothing crucial for us to add to what the narrator/speakers are saying, then we don’t describe anything.”

Anthony continued, “If, however, something must be described, we either fit in one- or two-word descriptions in any available lull in audio or decide to “talk over” the least relevant audio–false starts such as “uh, um” or repeated audio, etc. If the video elements require more detailed descriptions, we have the option of timing our descriptions to be read either before or after the section.”

There is a clearinghouse out of Spartanburg, SC, the Described and Captioned Media Program,  http://tinyurl.com/n2q9fq  that keeps track of providers of closed-captioned and audio description providers, as well as those video houses that can encode the finished files back into the original SD and HD programs (like Video Labs http://www.videolabs.com/, the company I work for).

These good folks at DCMP sent me a a link on their site that gives you an excellent example of a video soundtrack before and after “audio description.” http://bit.ly/614uL

Anthony DeMarco of NCI also mentioned that they are other audiences besides the visually-impaired who can benefit from audio description.  “It can provide benefits for virtually any viewer.  Even a fully sighted person can use the description as a learning tool, helping him or her identify unusual or subject-specific objects such as woodworking tools or military items.  This usage applies equally to new English language speakers and children of any age, helping them build vocabulary.”

(And fyi, NCI also provides audio description services in Spanish for Spanish programming.)

And finally, Anthony muses that audio description “provides something most sighted viewers can relate to at one time or another . . . the added benefit of keeping one engaged in a given television program when he or she leaves the room but is still within earshot of the TV.”  

One other final note, you may not be aware that many cinemas these days offer special showings of movies with captions and/or audio description. http://tinyurl.com/dcnspx

As always, your comments are welcomed below:

You can reach Anthony DeMarco at ademarco@ncicap.org

And you can contact David Ryan at dryan@videolabs.net

If you found this article of interest, I invite you to check out these other blogs about captions and subtitles:

Our HD captioning services at Video Labs: http://tinyurl.com/6bpxje

The challenges of captions and subtitles for DVDs: http://tinyurl.com/5vgp9m

Captions for HDV tapes? http://tinyurl.com/cpwfan

Captioning & Subtitling options for Blu-ray discs: http://tinyurl.com/me7quf

And don’t forget to “follow me” on Twitter for exclusive time-sensitive media replication & multimedia discounted specials: www.Twitter.com/DRMediaSolution

OK, so your video editor comes to your desk and says that the video clip you wanted is ”320 x 240,” . . . and you basically rely on the look on his or her face as to whether that is a good thing or bad thing.  Sound familiar?

Let’s see if we can’t help you look a little less like a deer in the headlights in such situations.

Again, my disclaimer, I myself have had my deer-in-the-headlight moments, and I am not a bonafide engineer (I only play one on TV - ok, ok, I couldn’t resist), but over my years as a producer, director and editor, I picked up info along the way — at least enough to help me survive. (though some might say I know just enough to be dangerous, but let’s ignore that, ok?)

With that all said, let’s move on to the topic at hand.  Video Resolution: it all comes down to pixels.

Those are the dots, with color components in them, that get energized by an electric charge to create a certain brightness and color.   And seen together, all those pixels make up an image.

And the denser the arrangement of pixels, the higher resolution the resulting picture is.

A standard definition television screen is made up of 525 horizontal lines and 720 columns of pixels.  Do the math and you get a conceivable 378,000 pixels.  

In reality, only 480 of the 525 video horizontal lines in SD are actually used for the picture.  The other 55 lines are not seen on regular screens.  They make up what’s called the “vertical interval” where such info as closed captioning, Sigma and SpoTTrac-ing info (see my blog on those:  http://tinyurl.com/65c2hp ) and vertical interval time code are carried.

So, the resolution for a regular standard def full screen tv picture is usually stated as 720 x 480 (with the 480 actually alternating scanning of even and odd 240 lines — see my blog about 24P that includes info about the differences between progressive and interlaced: http://tinyurl.com/57eghk )

And yes, even those 720 columns sometimes get cut down to 680 through other electronic shenanigans.  Oy vey.  What’s a viewer to do?

Now you know what drives the movement to HD.

High Defitinition resolution ranges from 1,980 columns of pixels and 1080 horizontal lines (scanned interlaced) — to 1,280 columns of pixels with 720 progressively scanned lines.   Do the math for either, and you’re looking between 921,600 to 2,138,400 available pixels. 

Higher Definition does indeed mean higher resolution.

Now, there are “super-duper” HD formats that are used by high-end moviemakers.  You’ll hear the terms 2K and 4K associated with those.   Check out this link to a popular high-end HD camera, The Red Digital Camera. http://www.red.com/ 

What’s going on is that these higher-end HD cameras are increasing both the number of columns and lines of pixels in a frame — part of the on-going quest to get digital filmmaking to match 35mm filmmaking.

Chris Vazquez (of “Ask Chris” on this site http://tinyurl.com/9l9xre ) sent me an article about where a 4K projector is being used http://www.vrac.iastate.edu/c6.php and its increasing popularity.

So let’s go back to my original statement, where the editor tells you the image is 320 x 240.  What’s going on with that?  This takes us the opposite way.   Think now . . .  yes, that’s like half the size of a regular standard def picture.  Hmmm, what could be like that?  And then you remember the term  ”compressed video” . . . video that can be played on a CD rather than a DVD, where the image doesn’t fill the whole screen. 

Yes, what the editor is telling you is that the video clip is not intended for full-screen video.  It’s set up to be played off a CD, or in a standard PowerPoint presentation, or perhaps on a website.

This topic can get much more detailed, and I invite you to check out http://en.wikipedia.org/wiki/Pixel and http://en.wikipedia.org/wiki/Display_resolution, but I hope I have given you some initial grasp of the world of video resolution. 

I welcome your comments below.  And feel free to contact me at dryan@videolabs.net or 301-217-0000 x104 with any questions.

If you found this article of interest, you may want to also check out Chris Vazquez’ article about “anamorphic” images.  http://tinyurl.com/59jtfd

1080i, 720p, 24P . . . oh my!

30 frames, 60i, 25 frames, 50i, 29.97, 23.98.  Somebody help!

Here are links to two in-depth articles on the web that I found that does an excellent job in explaining what all these terms all mean: http://tinyurl.com/ysxs4h   http://www.answers.com/topic/24p

But if you want a quick-read summary, I’ll give it try.  Please read on:

Let’s start by asking, what makes you sense motion on film or television?

Well, it’s a series of still frames projected fast enough so that you perceive the result as one continuous motion. 

How fast do the frames need to be projected?

Well, for most of the history of film, the projection rate has been 24 frames per second.

But when television came in, being an electronic medium, it made sense to the developing engineers to base the frame rate of that to match the electrical systems around the world.  And the electrical system of the US is based on 60 hertz, or cycles, per second.

If you have traveled internationally, you know that the electrical systems in some other parts of the worl are based on 50 cycles.

So you might think it would have made sense to have 60 frames of video in the US and 50 frames elsewhere.  But that was thought to be overkill and take too much broadcast bandwidth, so the developing engineers came up with an ingenuous way that called for the scanning of every other line of the picture frame. 

The result was that within the 60 cycles of every second, the cycles would alternate such that one would scan only the odd numbered lines of a frame and the next one would scan the even numbered lines.  That process is called “interlacing.”  Do the math, and the result is 30 complete frames a second, still faster than the 24 frames per second of film.   And you can see then that in the countries with 50 cycle electricity, the result was 25 frames a second.

The quest was then on over the years to try to get television to look like film.  Well, the advent of high definition television has made that goal finally achievable.

First, the shape of the high def 16×9 rectangular wide screen matches that of a theatre film screen.

Then the high resolution of HDTV (many more lines per frame than standard definition) now rivals that of film.

While some HD formats utilize an “interlacing” line scan approach (e.g. 1080i), others are able to use a sequential line scan approach that is called “progressive.”  The thought is that a “progressive” approach provides a even clearer picture quality.  An example of that is the HD format 720p.

A final step in striving to achieve a film look for video, was when modern camera technology allowed for the shooting of HD video at 24 frames per second.  These video cameras and recorders still work off of regular 60 cycle electricity, but they manipulate the picture digitally (via a 3-2 pulldown process — again, refer to above link for more details on that) with the result being that 24 video frames are recorded in one second. 

OK, that takes care of the 24.  But what is the “P” in 24P all about? (notice it is usually written as a capital “P” when used with 24)

The “P” here does indeed refer to a progressive scan rather than interlaced, but this is not to be confused with the the “p” and “i” in the scanning of the lines in the original frame.  24P means that the the resulting frames created in the “pull-down” process mentioned above are scanned progressively. 

To demonstate the point further, consider this — it is possible to have a 1080i HD tape that has been recorded  in 24P.

Is your head starting to hurt yet? 

Well, just one further thing to make it swell a bit more.  When color television came in, there were technical interference issues in introducing that element to the NTSC television signal such that the nice and logical 30 frames of video had to be slightly adjusted to 29.97 frames per second.  And brother, have we “non-rocket scientists” had to work hard in wrapping our heads around that one! 

So sure enough, as a result. in our NTSC world, for all intents and purposes, what we call 24P is really 23.98 frames per second.  (Now there are exceptions to this where true native 24P can be carried through in the production workflow to display – see above mentioned in-depth articles for more on that)

Whew.  I hope that helps make things at least a bit clearer.  (I am sure some of you are saying, “Yeah, sure, David.”  Oh well, I tried.)

Regardless, just know that we can handle your 24P tapes here at Video Labs, both in dubbing and editing.

Please contact me with any questions.  dryan@videolabs.net

I also welcome your comments below.

You may also want to check out that Video Labs also offers HD captioning: http://tinyurl.com/6bpxje

. . . and SpoTTrac encoding: http://tinyurl.com/6yq8zo

Look at the many steps that footage typically goes through before getting to air or distribution.

And these steps are often further sub-divided or expanded. 

For example, portions of the video during the editing might be sent off to the graphics department for added effects work — with the resultant composited footage then brought back into the editing.

And after a program is finally edited, the sound is often stripped off and sent to an audio mixing facility for “sweetening.”  Then that new mix is brought back into the edit system and conformed to the picture before the program is laid off to the edited master tape.

You might ask, does maintaining unity gain really matter in this digital age?  You might be thinking, what with all the computers being used throughout, can’t one just adjust levels digitally as needed at any point along the way?

The problem with that thinking is that making radical adjustments at any stage in the pathway can introduce “noise” in either the video or audio.  Plus, you can correct only so far. 

Here is an everyday example of what I am talking about.  You may have tested the limits yourself when working on an underexposed digital photo in Photoshop or similar graphic program.  Sure, the computer software allows you a lot of correction ability that was unimaginable just a few years ago.  But chances are, if the photo is seriously underexposed or “out of whack” color-wise, you will be limited as to how much correction you can apply.  Despite your best efforts, chances are you will not be able to get the image to look very good.

Now, let’s look again at the production/post-production path chart – and think of every step as a point where the picture “gets taken” by your camera – an opportunity to affect the signal . . .
 
See the importance of maintaining consistency – or unity gain?

And the same goes for audio.

So how does one maintain consistency throughout the production and post-production chain?  How do we know what the intended or proper Picture and Audio levels are at any point in the production/post production process?   How do we know what is real?

The two basic metrics used to confirm proper levels are SMPTE (Society of Motion Picture and Television Engineers) bars for video, and 1K hertz tone for audio.  Check out this link for more details on those: http://tinyurl.com/59xckj

That is why it is standard procedure to lay down at least 30-secs of bars and tone at the beginning of every tape shot in the field and on every edit master and subsequent dub master.  Bars & Tone provide an industry reference.  When you release your videotape for broadcast or duplication, the 30 seconds of Bars & Tone at the beginning of your tape insures all of your hard work will be reproduced accurately.

For those dealing directly with the technical aspects of production and post-production, there are other intricacies to keep in mind when calibrating equipment in the signal path to bars and tone.  For video, there is component video http://tinyurl.com/pgvyh, SDI (serial digital interface) http://tinyurl.com/2u4wvp and of course the burgeoning High Definition field http://tinyurl.com/6c7d8j  &  http://tinyurl.com/5s6y8h

Also, remember to check the calibration of your “reference set-up equipment.”  About once a month check the calibration of your color monitor, waveform/Vector scope and the Audio Meter.

For audio there is the variable of whether the meter you are using is a VU (volume units) or PPM (Peak Program Meter).  Read more about that here: http://tinyurl.com/6xzp3d

And there is also the realm of digital audio to consider.  Formats such as AES http://tinyurl.com/676et3  and Dolby 5.1 “surround sound” http://tinyurl.com/onwte

One last note about audio meters and tone.  If the audio meter is “summed Mono” (Left & Right channels combined), the meter will read 3 dB hot when playing tone on both audio channels at the same time.  Always play the audio channels one at a time to confirm proper Tone level on a “Mono Meter”.

Suffice it to say that unity gain is important to always keep in mind whether you work in a large production facility or an indie production boutique.  Almost every broadcast and cable network insists on a strict quality control review of programs being considered for air.

If unity gain has not been carefully maintained throughout the production control, I can almost guarantee you that issues will arise that will result in the program being rejected.  And as a producer or technician, that is something you do not want to hear.

So, avoid that frustration (and added expense).  Watch your levels closely throughout the production and post-production process.  Insist on unity gain throughout.

Your comments are encouraged below.

Feel free to contact Chris Vazquez at chris.designsmith@verizon.net or 301-953-1427.

Other articles you might be interested in:

Is there generation loss in digibeta?  Check out Chris’ article: http://tinyurl.com/6yd6gn

Curious about setting up your editing timeline correctly?  Check out David’s blog: http://tinyurl.com/5mbl8u

Need CD, DVD or tape duplication?  Contact David Ryan at dryan@videolabs.net or 301-217-0000 x104

The ”democratization of video” marches on, and I am right in step.  Every month I receive more and more orders from clients who send me completed programs that they have edited on their own systems — often inside a powerful laptop. 

I usually receive either an edited master videotape or a portable hard drive.  (check out my blog of indies, miniDVs and portable hard drives: http://tinyurl.com/6agsm4) 

Taking advantage of our wide array of videotape machine formats, a client usually wants us at Video Labs to either make additional videotape and/or DVD copies of the finished program.

All very fine — bring it on! 

The only downside to this “democratization” movement has been the relaxation — usually unintentionally — of some essential technical guidelines, that if not followed, can cause havoc.

Don’t get me wrong — I am not a snob.  Unlike some other media veterans, I welcomed the dilution of the oft-used elitist term, “broadcast quality.”  Those walls were torn down thanks in large part by the video music realm.  And I for one think it improved our business by ushering in exciting new programming.

But with more people producing and editing programs for broadcast or cable that do not have what we used to call “station” experience, I sometimes receive masters that have indeed strayed a bit too far — that will end up being rejected by the quality assurance review process of a broadcast or cable entity.

One frequent issue is the use of time code on program masters. 

Simply put, time code is the unique address given to every frame of video (30-frames per second in NTSC).  The address is expressed in terms of hours : minutes : seconds : frames.  For more background about time code, check out this link:  http://tinyurl.com/5v8uqz  Time code can range from 00:00:00:00 to 23:59:59:29 and then it starts over again.

Of course, nothing is easy in this field – so just when you thought you understood that, there is one more twist: the difference between non-drop and drop-frame timecode.  Check this out for background about that: http://tinyurl.com/4qsnrg 

All you really need to know is that drop-frame timecode is best for accurately following our normal clocks.  

Follow this example:  Let’s say you set up your editing time line so that the program begins at 01:00:00:00.  When the program is laid down with drop-frame time code, and you go to 01:30:00:00, the difference is exactly 30-minutes as you’d think.  But when using non-drop time code, the actual duration would be a couple of seconds more.

Now, let’s pretend you are in the master control center of a broadcast or cable entity.  You have a gazillion tapes around you and a number of playback machines that have to be triggered automatically and precisely at the right time.  Now think about it, if you were in that situation running programs and station breaks, wouldn’t it be really convenient to be able to easily tell how far you are into a program without having to rewind back to the beginning and timing it?

Well, think of the time code example I used earlier.  What if every program was indeed encoded in drop-frame time code, with the program starting at exactly 01:00:00;00?  Sure enough, by monitoring the program at any point during playback, one could tell how far into the program they are.

You might ask why not have the program start at 00:00:00;00 then?  Well, think about what time code number comes right before 00:00:00;00?  It’s 23:59:59:29 (yes in both non-drop and drop-frame realms – 2 frames are not dropped at the 10th minute mark in drop frame: http://tinyurl.com/5k5dhu) – and that is higher numerically than 00:00:00;00.  That violates another time code rule:  a tape needs to have continuously ascending time code or else it will cause extreme confusion.  That’s because the editing programs and playback machines  all operate on the premise that going to a higher timecode than a present location means fast forward — and to a lower time code means rewind.

So this leads us to the another dictum in setting up time code for editing sequences.  Let’s work backwards.  On a program tape, there should be 60-seconds of bars and tone, 20-seconds of slate (text with information identifying the program) and then a 10-second countdown that goes to black at 2.  If you do the math and subtract from 01:00:00;00, it comes out that bars and tone then should start at 00:58:30:00.  Give yourself a few seconds of pad before that, and you get 00:58:20:00.  Check out the diagram at the very top of this article.

There you have it.  So, if you are editing a program that might be “aired” on broadcast or cable, start your timeline at 00:58:20:00 and use drop-frame time code.  (And no, it is not easy to change time code for an editing sequence after you start editing.)  So get in the habit of setting that all up before doing any editing.

Now, there is one post-script to all this.  Tradition has it in the corporate video world to follow the same rules as above — except they use non-drop time code rather than drop-frame.  Frankly, I gotta tell you, I am not sure why that occurred over the years, but I believe it developed because such non-broadcast programming is usually shorter and there is less concern about being exactly time accurate during playback.  With that being the case, sure, not having to deal with ”dropped frames” is indeed easier when making clip calculations.

Post your comments below or e-mail me at dryan@videolabs.net 

Having issues playing back your Canon HDV tapes? Check out http://tinyurl.com/5jvb9y

They are the three main broadcast standards in the world, and the broadcast telelvision signals of a particular country are one of the three (some countries do have two). 

For a complete list of the standards in the world, check out http://www.sivideo.com/9stand.htm

We here in the USA are NTSC, while most of Europe is PAL.  France and a number of countries in Asia are SECAM.  

PAL and SECAM are quite similar, and since the requests for our making SECAM dubs is very rare here at Video Labs, I’ll confine my comments in this article to NTSC vs. PAL.

In Standard Definition video, the color and brightness information is carried via analog information, in otherwords, by fluctuations of voltage.  In the HD world, that information is determined digitally, in other words, by fluctuations of good ‘ole digital 0′s and 1′s.

But one difference between PAL and NTSC is the same in both standard definition and high definition television –frame rate.

And those frame rate differences go back to the differences in electrical cycles in the world.  For example, the electricity here in the USA is 60 cycles/sec.  And if you have traveled to Europe, you know that you cannot plug in your electrical device from here without a converter.  That’s because the electricity there is 50 cycles/sec.

You can see then why there are 60 frames of video per second in the USA’s NTSC televison signal and 50 frames per second in the PAL system. 

So, getting those good ‘ole British TV shows to play here in the US, and ours to play over there, requires a conversion process — otherwise known as ”standards conversion.”

We here at Video Labs have a various equipment to convert programs recorded in one standard to the other. 

A main challenge in standards conversion is combating ”judder.”  Think of it as a combination of the words “jitter” and “shudder.”  You probably have seen the artificat sometime when watching a program from Europe played here in the States.  It is most noticeable when there is a horizontal movement or the camera pans.  I personally have noticed it being most pronounced in scenes where people are crossing the street and the camera pans.  The result is an awkward gait in the folks.

Video Labs is one of the few places around that has the Snell & Wilcox Alchemist Ph.C, which is the recognized leading device in minimizing “judder.”

The secret is in the “Ph.C,” which stands for phase correlation.  It uses an algorithm process to best deal with the frame conversions.  Check out this link for more: (once there, hit Ctrl + F and enter “phase correlation”) http://tinyurl.com/cyutd

Now, full disclosure here — the Alchemist Ph.C we have is for Standard Definition only.  For converting HD tapes, we have both HDCAM and DVCproHD decks that can playback and record both 60i and 50i (remember from above, 60 = NTSC and 50 = PAL . . . the “i” refers to “interlaced” vs. “progressive” — but that’s another article).  We use our Final Cut Pro with its Kona card as a “conversion interface,” if you will, in that process.

I’ve just touched the surface of standards conversion, but be assured, the Video Labs team and I can get you where you need to be if you have project requiring that service.  Just give me a call at 301-217-0000 x104 or write me at dryan@videolabs.net

Curious about standard definition “anamorphic”? Read Chris Vazquez’ article: http://tinyurl.com/59jtfd

I’ve been filming – or attempting to film – red foxes in my neighborhood for one of my new independently-produced segments for Maryland Public Television’s weekly series, Outdoors Maryland. It occurred to me during my stalking endeavors that pursuing foxes is not unlike pursuing viewers of a media production, whether documentary or corporate, video or website.

In both cases you have a “quarry” who is preoccupied with their industrious lives. Finding a way to grab their attention – and winning consent to your themes or messages – requires ongoing research.

In other words, know your prospective audience. I’ve walked up and down the street day after day talking to neighbors about the habits of our fox family – where the male and female and two pups roam and when they seem to be most active. Many have a theory about where the foxes have a den. Others have seen them carrying hapless squirrels.

Researching your viewers means more than simply knowing their principle products or general interests. Find out the current issues specific to that enterprise, including struggles, successes and goals – get to know the neighborhood.

Surfing the web is a good way to start. Read news accounts about the industry or association. Scrutinize their publications. Most importantly, talk to people on the ground. If you can, visit the offices or organization to get a sense of the culture.

Incorporate technology and jargon, but don’t overload and outdate your production with passing fads. I’ve learned that the yard the fox runs through today may not be the yard he or she runs through tomorrow. You need to figure out the range of your target audience’s interests.

Keep in mind, these concerns are not necessarily the same thing as the key messages or themes your client or funding agency want delivered. The interests of both client and audience need to be reflected if you are to engage your quarry productively.

In other words, don’t assume that the viewer will be interested enough to act just because you’re out there with an urgent message vaguely related to their field.

One mistake I made early in the pursuit of foxes was staking them out in areas where I thought, after diligent research, that the foxes had a den. I spent hours and hours waiting in a camouflaged hunting blind, alone with a camera or with a second cameraperson. During this endeavor, I captured not one frame of video of a fox. I did get one or two shots of squirrels and a deer.

The footage I do have so far was captured by driving or walking around — camera ready — and rolling when we spotted our moving target. Don’t expect your audience to come to you.

Happy hunting. I’m still on the trail….

You may reach Susanne Stahley, Writing Consultant, at scstahley@verizon.net

Read about Susanne’s recent Emmy award: http://davidryanmediasolutions.com/davids-website-picks/