summary: digital video

[Ulrike Zeshan]

Dear colleagues and friends,

this is a summary of all the message I got in response to my query about
"going digital" with video data. Some of them also appeared on slling-l,
but  am summarizing everything again here, as well as repeating the query
itself. I hope some of this will be useful for you (it certainly was for
me, I can see my options much more clearly now!) In the summary, unmarked
passages are from respondents, passages marked with stars ** are my own
comments. Thanks to all the helpful respondents:

Doug Stringham
Dan Parvaz
Alex Bonucci
Onno Crasborn
Susan Fischer
Chris Miller
David McKee
Jean Johnson/James Womack
Rebecca Orton

You will see that there are many issues, and I have rearranged all
responses into categories for easier reference.


MY ORIGINAL QUERY:

this is a call for technical expertise from people on the list, of which
there is a lot out there, I am sure. In short, the problem is this: I have
so far used analogue video recording (VHS), but I want to go digital now.
Since I don't have a lot of technical knowledge, it is a major and very
time-consuming problem for me to find out what will be best for me to get.
Of course, salespeople are not used to people using video for sign language
research, so who could give you better advice than other sign linguists
working with digital video. Based on what I need to do with my videos (see
below), I would like to invite your suggestions about what hardware and
software you think is good, or you are using yourselves. If there are
enough responses, I will summarize for the list.

Here is what I will need to do:
- digitize some old VHS videos, as well as outputting some digital video in
an analogue format; that is, I would like a system where the input can be
either analogue or digital and the output can also be either analogue or
digital;
- edit video, including cutting up the video in smaller pieces (files),
fade-in/fade-out, sub-titles, removing the audio (voice) or adding on a
voice, adding written titles in between, capturing single frames and saving
them in separate files; this is for producing educational materials in
India and for getting examples to go with published articles and books;
- I will want to use some sign language analysis program on the digital
video data; my favorite so far is the analysis-cum-database program they
are developing in Hamburg, but I am not sure if it is ready yet, otherwise
either SignStream or SignWriter may do;
- of course also video filming in a sign language research setting.

I am using the following hardware:
Macintosh PowerBook G3, HD 3GB, FireWire and USB connections,
CD-ROM/DVD-drive, MacOS 9

Apart from general suggestions, I am specifically interested in these
questions:
- Do I need a special video editing program, or can the functions I need be
covered by camera-internal functions or functions in a
SignStream/SignWriter-like program?
- If I should have an editing program, which ones do people use and what
are the experiences?
- What is the most efficient way to store large amounts of video data (I
will have at least 10 hours of video data each from my two next field
trips)? Store it on a CD-ROM? Record it back onto the video camera?
- Are there any problems of compatibility that one should aware of? I
wouldn't want to get any hardware or software that is not going to work
together with the rest of my system.

Thank you very much for your suggestions. I am sure other people have gone
through some of the same questions when going digital, and others may be
thinking about them. For the benefit of the latter, I will summarize
responses for the list.


RESPONSES ABOUT VIDEO EDITING:

** For the Mac, iMovie seems to be everyone's favorite, best value for
money. For more advanced applications, there is Final Cut Pro, also from
apple.**

iMovie allows you to edit video, create simple transitions, capture
frames, and save all video to respective files. Do some reading at
http://www.apple.com/imovie/ for this info. You'll be amazed at what
is available for consumers. Its learning curve is quite shallow, I
assure you, and oh, by the way, it is free.
** As far as I understood the website, it's free only if you buy one of the
new Mac computers. Otherwise it's US$ 49.- (download version), which is
still incredibly cheap (other programs can cost well over $1,000, and
though they are more sophisticated, iMovie does the job just as well for
sign language purposes, I think.**

Given your hardware, I suspect that iMovie (which you may even
already have) will do the job just fine for the kinds of editing you are
talking about.

Apple's Final Cut Pro is for the video professional
(http://www.apple.com/finalcutpro/) and is a much more robust package
for editing and effects. You may find this necessary depending on
your desires.

Install iMovie 2 or final cut Pro that are software to digitize.
**BUT note this:**
One thing to keep in mind if you want to work with iMovie (whatever version)
  is that it only reads *digital* video files and not analogue files, which
is why you need a separate digitiser as Alex suggests. Otherwise, Final
Cut Pro can read either analogue or digital files.

For editing purposes, I find iMovie adequate for our purposes.
However, if you have large volumes, then get a Mac with lots of GBs
(30-40 GBs).  Final Cut would be a better editing program but at a
steep price.

**also note**
Learn how to make DVDs of your video with Apple's iDVD,
http://www.apple.com/imovie/share.html.


RESPONSES ABOUT DIGITAL AND ANALOGUE DATA AND DIGITIZING:

**Staying all digital clearly seems to be best. While going from digital to
analogue is easy (although no-one actually said how it is done!),
digitizing (and compression) is more complicated, but can also be done with
various devices.**

I currently make my exams with these methods (iMovie, not iDVD) where
I import analogue video into a digital environment (nearly realtime,
thanks to Apple's compression techniques, i.e. Windows compression
time ratio is 1hr:24 hrs, whereas Apple's compression ratio is 1:1,
an unbeatable advantage), edit the video based on exam needs, and
then re-export analogue video to VHS for use in the college's video
systems. DVD is coming for our school, and I plan to take advantage
of this for testing purposes.

**I found the information about compression rates particularly interesting.**

If you want both analogue and digital capabilities, you'll need both
systems; traditional VHS as well as a digital environment to go back
and forth. The bad news is that it is tedious. At this point, and
with available technology, its better to stay digital. Space and
storage become the issue.

If I had the resources, I'd be doing all  of my testing digitally using the
means I outlined above. It's quick, easy, and over the long run, cheaper.

convert all your VHS material in DV tape format  there is a special video
tool for that:  it is the JVC  HR-DVS1MS that can convert a VHS or SVHS
format  in Mini DV tape.

** I didn't quite understand what this device is. Is it a camera? (some
cameras can convert analogue data to digital), or is it  something like a
dubbing device that does the conversion at the same time?**

Connect your Videocam DV  or the JVC  HR-DVS1MS that are both FireWire to
your powermac G3 and digitize.

Of course, if you wanted to read movies in from your analog camera on
your G3 laptop, you'd need a separate PC card to accept input (which, of
course, is a sophisticated analog-to-digital convertor). The G3 laptop
has S-video *output* straight out of the can, but no analog video *in*.
I believe FireWire is the only built-in option.

**Some digital cameras, as they tell me, can actually convert analogue data
to digital, but I haven't seen how it works. Apparently, you connect some
analogue video source (camera, VCR?) to the digital camera in an "in" plug
and you get digital data via the "out" cable. If it works, this means you
won't need an extra digitisation device (I don't know how expensive they
are, if it would matter a lot). I also don't know if it is efficient enough
in terms of time.**
It's easy to go from digital to analogue.  Vice versa is trickier, but can
be done.

One less encouraging note: in the Netherlands, the sign language
community received a large grant to digitize all the video recordings
from past research (many hundreds of hours). So far, no
computer/video company has managed to deliver a system that managed
to digitize a whole tape of 2 hours and compress it to MPEG-2 (a
recent compression standard) in one go: each time the video and audio
would get desynchronized at some point. Even expensive broadcasting
systems didn't perform the trick. The problem appears to be in the
computer card that does the MPEG compression (the second stage, after
the digitizing, for which there is also a separate card). If you do
the compression with software instead of a specialized chip, you
would not run into this specific problem. Software compression is
slow (1 hour takes between 20 and 30 hours to compress), but if you
have the time, and if you don't have huge amounts of material to
compress, then it is no problem.

**note the comment above about possible 1:1 compression rate**

We still have no solution that works, but the lesson we learnt is
that one should make sure that the whole system actually works before
one buys it (never believe the salesman...),  ((**couldn't agree more with
this!**))
and that you will prevent problems if you digitize smaller pieces of video
at a time
(e.g. 15 minutes). This will also make it easier later to make backup
copies, or to copy material from a CD to your laptop to work with.

I use a Sony VCR (SLV-T2000) that can play both Hi8 and VHS tapes.
In fact, you can record from either format to other.  Also I use a
Sony digital 8 video camcorder which also can play Hi8 videotapes,
however, it can't record in Hi8 format.
What I would do is play Hi8 tapes in the digital 8 camcorder and
transfer them to iMovie on Mac computer.  Also you can record
analogue VHS tapes onto Hi8 tapes and then play them in the digital
camcorder.


RESPONSES ABOUT MAC AND PC PLATFORMS AND HARDWARE:

At least you are on the right platform. The Windows/PC world is not
ready for this and Apple has made huge consumer (read: affordable)
strides in personal digital video. By way of background, in addition
to working as an interpreter instructor and rater, I also work as a
senior designer in an advertising/design/marketing agency. I have 15
years of Macintosh experience and understanding.

The best system for this is a newer G4 tower, with the new
SuperDrive/DVD-RW (read-write) drive built in
(http://store.apple.com/1-800-MY-APPLE/WebObjects/AppleStore.woa/194/wo/E8Xr
E1FUtrckp8ppXC/0.3.0.3.30.11.0.1.3.1.3.1.1.0?72,15), as well as iMovie,
iDVD, and/or Final Cut Pro, all from Apple.

If you can, get a bigger hard drive. For editing video, 3 GB is nearly as
good as a floppy. 20 GB is more like it.
You didn't mention how much memory you have on that G3 laptop. More
is better.

** compatibility problems **
Just don't go to the PC world, and you will be fine. Again,
PCs/Windows are not up to speed in this arena. *That* would be a
disservice.


RESPONSES ABOUT STORING LARGE QUANTITIES OF DIGITAL VIDEO DATA:

**The available option are: FireWire drive (up to 75GB), CD-ROM (640 MB),
DVD (5 GB), ZIP-drive (200MB), DV tape (1 hour of video).**

This is the other Pandora's box of digital video: space and lots of
it. Your best, arguably cheapest, and most flexible solution is a
FireWire portable drive
(http://www2.warehouse.com/dept_find.asp?dept%5Fid=3908&cat=mac&sel=MacDrive
Fx). FireWire is a solid solution as it is portable, plug and play (not
plug-and-pray!) and are available up to 75GB, and you're going to
need it. I use a 30GB FW drive at work and find it faster than my
internal HD sometimes. Digital video is not stingy when it comes to
hard disk space. If you're serious about converting video, you'll
need the room. You can use CD as storage, but remember that CD's hold
up to 640 MB only.

You could also use zip drives.

It would be wise to keep uncompressed video on digital tape which may
serve as a "master" for future production -- should the need arise,
converting this to analog is trivial. For corpus management, having a
compressed version on a random-access medium (CD, DVD, disk) also has
its advantages.

**Good to know that digital to analogue is trivial, but how exactly would
it work and what kind of device does one need to do it?**

Make the film in your software and than send the final version on a DV Tape.

**This seems to me the easiest way for storing the video-only, but it would
not work, I believe, for storing the files generated in signwriter or
signstream. DV tapes are not very expensive (here about AUS$ 10 per tape),
quite in contrast to video disks that cost AUS$ 100 per piece here. There
is one camera that takes disks rather than tapes, and you should be able to
put this directly into your DVD drive and work with it. Could be very
handy, however, when I tried it in the store it didn't work on my machine!
The camera is more expensive too, and since it's the only of its kind, this
system may not live long.**

(may be you will need additionnal storage to digitize - e.g : 1 hour full
resolution = 40 GByte) For this you have some Firewire external disk that
can be usefull (75 Gbyte for example)

For the computer part and the file format you  need, it depends of what you
want to do :  CD rom ? Video trailers ? Video streaming ?       each can of use
have its kind of file format and compression format      (sorenson video or other)

We found that for analyzing the materials on our computer screen,
we don't really need the full screen (PAL: 640 x 480 pixels). If you
shrink the video a little bit during the compression, you could
reduce the amount of data while not losing much. This will depend on
the quality of your tapes, how much you zoomed in on the signer,
whether there is only one or two camera views in view, etc.

You may want to try to get one of the new desktop Macs with a SuperDrive
that lets you record DVDs;  A DVD can hold over 5 GB.  Otherwise, you can
probably put about 7-8 minutes of video on a CD-ROM.  CD's have the
advantage of being very cheap (I just bought 100 writable CDs for US$30)
and universal.

One thing to keep in mind is that you can compress your original huge files
to much smaller sizes using the Sorenson compression algorithms Alex refers
to (without
perceptible loss of image quality to boot), thereby allowing you to store
much more video in a given medium. The compression can take some time,
given the size of a raw video file, but the result more than makes up for
the wait.


ABOUT RECORDING DATA:

In Leiden we have worked with digitized video for a few years now; we
have a large collection of single-sign clips and single-sentence
clips. Lacking a transcription program like signstream which also
gives you rapid access to single signs / parts of your transcription
in a large piece of video (say, half an hour), that was the most
convenient way for us to get access to our data. Two specific
experiences might be useful to you:

1. We found that it is extremely helpful to be able to use two video
cameras. So far we had one camera from the side and one facing the
signer, so that we could get a good 3D view of the hand movements. In
the future we will probably combine a frontal view of the signer with
a camera zoomed in on the face (to look at prosody/nonmanuals in more
detail).
We used a JVC mixer to record the camera view synchronically on one
tape -- so we had no original tapes of the two cameras. I guess there
should be 'digital' ways to do this mixing nowadays, but my guess is
that it would still be easier to mix the views _before_ recording to
tape or computer. Synchronizing two separate recordings afterwards
can be problematic, as far as i have understood.

BTW, in these recordings, a time code that includes video fields
(50/sec for PAL, 60 for NTSC) is very useful. In our recordings, i
was generated by the JVC machine on which the combined view was
recorded. 'Simple' video software like iMovie may not do this time
code for you. In that case you could use the time code that the video
camera can put on the screen when recording -- but in our analog sony
camera there are only seconds, no frames or fields, in that time code.


IF YOU USE A PC:

I'm not a Mac person, I hate Macs even though I am forced to use
them sometimes.
However, based on my pc experience which may or  may not apply to
the person you quoted:
1. Simple cheap device for placing analog or digital video into
your computer is the 69.00 Belkins Video Buss II (now III). Also edits but not
to my satisfaction.
2. Software to edit can be VideoWave II or IV. I myself am
partial to
3. I recommend that you have at least a 30GB hard drive with at
least half of it free, better yet get a 60GB HD if you can afford it.
4. When I am done editing videos, I transfer the whole stuff to a
CD using a CD-RW. This is so I can keep my HD form becoming
overly cluttered with space hungry video files.
5. As skill increases, he may want to experiment with integrating
art into videos using Bryce 4 to alter backgrounds, the sky, inserting
objects like buildings, landscapes, etc.



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Dr. Ulrike Zeshan
Research Centre for Linguistic Typology
Institute for Advanced Study
La Trobe University
Victoria 3086, Australia
ph. +61-3-94673084
fax +61-3-94673053
u.zeshan at latrobe.edu.au
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