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100th Stupid Blog Entry!


Nathan Strum

2,292 views

Somehow, I've stuck with this whole "Blog" fad long enough to crank out 100 entries. And much to my surprise, just this past week, I passed Manuel's Blog as the "Most Viewed" at AtariAge:

 

top_10_blogs.gif

 

So to all of the people who have been reading my blog, all I have to say is...

 

...don't you have something better you could be doing??

 

;)

 

Seriously though, thanks for reading. Hopefully some of it has been interesting, and maybe, occasionally, even useful.

 

:lol: Pffft! Ha! I knew I couldn't keep a straight face with that one. :roll:

 

No, really. Thanks for reading. :D

 

Besides, as soon as Manuel starts working on Colony 7 again, poof! There goes first place.

 

And all the sweet, sweet prize money that goes with it.

 

What... you didn't know about that? Albert didn't mention any of this... ?

 

Maybe I shouldn't have said anything.

 

Anyway...

 

To do something relatively significant to mark the 100th entry for my Blog, I thought I'd post an update on the Stella at 20 DVD.

 

Fortunately, by sheer coincidence, it just so happens there's actually something to write an update about. Otherwise, you'd be getting some more homebrew reviews. (You're not getting off the hook that easily. The reviews are coming later this week.)

 

So then, here's where we're at with Stella at 20.

 

First, a little background.

 

Glenn (mos6507) originally shot the footage for Stella at 20 on a videotape format called Betacam SP. This is about the highest quality, analog, standard-definition format that's out there. For those of you who have the VHS version of Stella, you really haven't seen the clarity of this footage. Glenn had edited Volumes 1 and 2 of Stella at 20 on a non-linear editing system (NLE) called a Video Toaster Flyer. Even though this was almost ten years ago, and used a proprietary compressed format, it still yielded results nearly indistinguishable from the source tapes. When the editing was completed, the projects were then mastered back onto Betacam SP tapes, which were then sent off for duplication to VHS. In order to get the quality we want for the DVDs, we had to go back to the Betacam masters.

 

Unfortunately, only the master tape for Volume 2 still exists. Volume 1 was lost when the duplicating service that did the VHS tapes went out of business. Last weekend, Glenn lugged his Toaster Flyer up to where I work in order to try to play back the project file for Volume 1, and create a new master tape for it. Unfortunately, we weren't able to get it to load up and run. The best we could do was play back some graphics files and a few minutes of rare footage of the late Jay Miner, and output that to Betacam. The bottom line: in order to resurrect Volume 1, it is going to have to be completely re-edited from scratch, using the original source tapes.

 

Fortunately, all of the source tapes are indeed safe (and currently in my possession). So that's not a problem. Plus, I have a VHS copy of Volume 1 to use as a guide for re-editing the new version. Which is where things get interesting.

 

This may not end up being the same Stella at 20 that you may (or may not) be familiar with. It certainly won't be any less than the existing version, but it very well may be more. It may even be edited differently. Glenn has given me the opportunity to re-edit Stella, not just to re-create what he's already done, but to fit whatever vision I might have for the project. My initial inclination was to simply duplicate what he already did, since hey - it works! But as I'm going through the footage, I may find there are things that could be added back in that were originally cut for time (or a lack of direct relevance to the 2600), that are still interesting. Plus, since the aim for this is a DVD, there's more we can do with interactivity and non-linear playback, that wasn't possible for VHS. The possibilities are starting to really intrigue me. I think we can come up with some cool stuff for it. Whatever direction it takes, I want to be sure this remains Glenn's project. So he has the final say on it. But it's nice to be able to throw my ideas at the wall, and see if anything sticks.

 

Ideally, it would be great to include a "Stella at 30" retrospective, with new interviews with some of the homebrew authors and other 2600 hobbyists. But given that they're spread not merely all over the country, but all over the world, makes that logistically impractical at this point. So for now, I'm sticking to the footage we've got.

 

So, where exactly are we? Has anything (other than our recent adventure with the NLE) happened lately?

 

Why, yes! Thanks for asking.

 

I'm currently in the process of digitizing all of the master tapes into the computer, so I can start editing. To give you an idea of what I'm dealing with, there are twenty-six 30 minute tapes, plus 48 minutes of the aforementioned Jay Miner footage which I just found on a couple of unmarked Betacam tapes in the bottom of the box. (Yep, Glenn - it's all there! :)) So that's about 14 hours of footage to digitize.

 

The trick, is managing that much footage.

 

Fortunately, Glenn put together a very detailed shot list, which tells what's on each tape and where. This is through the magic of time code, which is what's going to become very important in the next few paragraphs.

 

Time code assigns a specific number to each frame on a videotape. You can't tell where anything is without it. Also important, is we want to end up with a brand-new Betacam-quality master in the end. Even though DVDs are highly compressed, we want to start out with the best possible quality master, prior to compressing it. (And of course, we want the best archival quality copy for safekeeping.) The problem is that to work at the highest possible quality (10 bit uncompressed), we're dealing with a data rate of 270 Mb/second, which works out to something like 1.7 TB (yes, with a "T") for all of the footage. Besides the sheer amount of storage, you need a full-fledged video-capable RAID to be able to handle that data rate, in order to be able to even see what you're editing in real-time. The plus side, is that when finished editing, is it's a straightforward matter to output the final piece to a new Betacam (or more likely, Digital Betacam) master. Since the end result is digital, it can be compressed directly from that file for use on the DVD, suffering as little generational loss as possible. (I'll put up a whole 'nother blog entry someday about DVD authoring, and even teach you how to sing "The MPEG2 Alphabet Song". It'll be fun!)

 

editing_stella_1.jpg

 

While I do have some access to such a system, I can't monopolize it, or its attached storage, (nor do I really want to camp out in that editing room) for however many months this is all going to take. The other big drawback here, is there's no back-up of the digitized media. So if any of it gets lost or deleted, it has to be recaptured from the master tapes again on that same system. This locks me into a single editing system, and severely limits the time I can work on it, plus it doesn't keep the project completely safe from others needing to use that system. So there needs to be another way. The key, is time code.

 

Having talked with an editor and technician where I work, it turns out the best approach for this project is to first make a dub of the Betacam source tapes onto a format called DVCAM. This is a digital, compressed format (similar to DV), which brings a couple of benefits with it. First, it maintains the time code of the original tapes. Second, it gives me a good-quality back-up of the original source tapes (currently, there are none). Third, when I transfer these into the computer, they're already compressed at a much lower data rate (25 Mb/second) which works out to a mere 157 GB for all of the footage. This means the entire project can fit on a typical FireWire hard drive, can easily be backed up to a second drive, and can be plugged into practically any Mac running Final Cut Pro, so I can work on the entire project almost anywhere. Even on my iMac in the comfort of my own home. Better still, DVCAM decks are a lot more commonplace than 10-bit uncompressed capture stations, so if I need to re-import footage during the editing process, I can do it pretty-much anywhere.

 

editing_stella_2.jpg

 

This is called offline editing. In this case, using the DVCAM footage as a more manageable substitute for the Betacam tapes.

 

Since this is all frame-accurate with the original source tapes, once I'm done editing everything as DV files, I can take my Final Cut Pro project file to the uncompressed capture station, load it up, and tell it to only re-capture the footage - from the original Betacam source tapes - that was used in the final edit. Admittedly, this will still take some time, as I have to feed tapes to the machine as it needs them, but it's still only a few hours at most, and the end result will be exactly the edits I created using the DVCAM footage, but at full Betacam quality, and without all the unused footage. Final Cut Pro simply replaces the DV footage with the uncompressed footage, and from there, we can create a new Digital Betacam master, as well as the compressed DVD version.

 

editing_stella_3.jpg

 

Also, even though the final master will be about 121 GB per hour, it's not likely to exceed two or three hours, so that's still a reasonable amount to fit on an affordable FireWire drive, giving us not only a new master copy on tape, but a back-up on a hard drive as well. Plus, there will also be the DVCAM back-ups, which are of a very high quality in and of themselves. (The dubs from Betacam to DVCAM are being done using component video, and balanced audio.)

 

To expedite this whole process a bit, I'm using two DVCAM decks. One for making the dubs from Betacam SP, and the second to transfer the DVCAM footage into the computer. The dub from Betacam to DVCAM is the likeliest place where there could be a problem, so that's the one I'm watching. Since going from DVCAM into the computer is a direct digital transfer of data, I can basically just let the computer do its thing, and keep a watch on it out of the corner of my eye. So for example, while I'm watching and dubbing tape #3 (from Betacam to DVCAM), tape #2 (already on DVCAM) is being dumped into the computer from the other deck. This is also giving me the opportunity to look over all of the footage, check it against Glenn's notes, and begin to get an idea of what's there. The biggest plus of this setup is that all of the equipment is already in my office. I don't have to book time in the uncompressed editing room to do it. I can slip this in anytime after work or on weekends that suits me. (Definitely one of the better benefits of my job.)

 

Once the footage is all in, I'll copy it onto a portable hard drive, and I can begin editing.

 

As for a timeline of when this will all get done... well, I've given Glenn a couple of dates that I hope to have 1) a rough cut of the project and 2) the final DVD done by. But until we get close to either making or missing them, I'll just keep 'em to myself. Suffice it to say, they're months apart. So don't go looking for this anytime soon. I will, however, post updates regularly to my blog as the project progresses.

 

Currently, I'm done with dubbing tape #9, and transferring tape #8, so I'm about 1/3 of the way through digitizing the source tapes.

 

I'll keep you posted!

6 Comments


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Looking forward to the next 100 entries! ;)

 

I always thought I lost the "most views" throne long ago to SpiceWare :ponder:

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Hi Nathan,

 

Your blog is one I frequent often. I look forward to updates and I still go back to your tutorial on label making to help with drawings I scan in from my kids.

 

You know I'm excited to hear about the Stella @ 20 progress! This is going to be great! It would have been a nice touch to hear from the homebrewers. Still, put me down for an order when the DVDs are done. I think I've watched my VHS versions too much. They might be starting to deteriorate :ponder:

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Looking forward to the next 100 entries! ;)

 

I always thought I lost the "most views" throne long ago to SpiceWare :ponder:

:D - nope, I don't think I've ever been first in any sort order of the blogs ;)

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10-bit uncompressed at what sampling rate? 910fH 4:2:2 I bet.

 

Is the timecode stored on the Betacam SP tape (i.e. not just an offset from start of playback)?

 

The only problem using DV as a source for DVD is the 4:1:1 versus 4:2:0 chroma subsampling. (Although 4:1:1 makes perfect sense for interlaced sources while 4:2:0 gives the famous chroma bug which plagues many DVD players and STBs.) But what you're doing makes perfect sense for off-line editing.

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Yep, it's 4:2:2. The i/o uses SDI to and from a Digital Betacam deck (SMPTE 259M).

 

The time code is on the Beta SP tapes, and to this point, is unbroken on each one. If there were time code breaks, I'd have some issues to deal with. But so far, so good. They did a really nice job shooting this stuff.

 

(For those wondering, this is a nice, concise description of video sampling. One with pictures (pretty!) is at Wikipedia.)

 

I'm still learning a lot of this stuff myself. We had a really good guest lecture on HD last year at work that taught me quite a lot. But I rely on the other technicians at work to fill in a lot of the blanks* when it comes to video. I'm more a Mac guy, than a video tech. But I know enough to know who to ask. ;)

 

* Pun not intended. :ponder:

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I had the opportunity many years ago to play with video working for a division of Scientific Atlanta and I've added to that knowledge base over the years. One advantage of NTSC is it's been around for 50 years so is well documented (unfortunately, there's a lot of bad documentation out there as well). I happened to stumble across a PDF of a reference document which contains almost everything I have ever needed to know about analog video.

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