Dave Clemmer's Audio/Video Bookmarks
This page has been sitting statically for far too long. As mentioned, I wrote
this page when I was building my home theatre setup. That was a couple of years ago.
Since then, I've not only learned a lot, but I've found many more sites. (To
say nothing of the fact that many of my links broke, due to companies going out of
business or changing their URI's.)
First of all, a must-see site for movie enthusiasts everywhere. Internet Movie Database
For information more specifically oriented towards upcoming movies, check out Corona.
If you're curious about all-time box-office takes, check out Movieweb. (This does not take into
account inflation).
For news about what's happening in the broadcast industry, take a look at Multichannel News Online.
I'm a big fan of laserdisc, and have been for some years. For a long time, that's
what I had hooked up for a video source (well, that, and a cheap TV antenna :) on my
system. If you don't know what LD is, look here. It gives a nice introduction.
(The short of it is, though, that LD stores the FM signal that goes straight to the
screen, and has two soundtracks (digital and analog) to go with that. It's pretty
much as good as you can do for an analog medium.)
I've recently been convinced of DVD's viability. There seems to be a slight
improvement in screen resolution (my tests have been pretty subjective, however), but a
huge improvement via keeping the brightness and color information (luminance and
chrominance) separated, which gets rid of a lot of NTSC (remember, it actually stands for
Never Twice the Same Color) artefacts. It is highly dependent on the encoding being
done well, however, as the MPEG-2 algorithm used can get very bad if the bitrate gets too
low. Studios have been doing a pretty good job with that, however. I might
write a more detailed introduction to DVD one of these days, but I'm not going to bother
today. DVD does offer a few other marginal benefits, eg: multiple soundtracks and
subtitle tracks. The only thing to keep in mind here is that there's only one
bitstream, so the more soundtracks you have, the more it'll cut into picture quality.
As long as it stays with 2-3 Dolby Digital soundtracks (which,
IIRC, max out at 448kbps), it's not a big deal, but as soon as you have one or more dts tracks (which can easily exceed 1Mbps),
the bandwidth requirements necessitate a shorter, or lower quality, program. DVD
does have some rather irritating add-ons, however. These are called region coding
and macrovision. I'll talk about these in some more detail later.
Comparing LD and DVD (which I saw much of some while back), there are plusses with
each. LD is free of digital artefacts (posterization and such), while DVD is free of
analog artefacts (blooming, speckling, etc). LD does offer easier access to
individual frames (even my THX-approved player can
easily start playing slow-motion, instead of frame-by-frame; also, DVD can't really search
backwards frame-by-frame). One problem with DVD, though, is that it can be difficult
to tell how the sound on a given disc is mixed (ie: mono, stereo, matrixed Pro-Logic
surround, or fully discrete 5.1 AC-3), due to them always being Dolby Digital (which
generally refers to the latter, but supports all of the above). In addition, it
seems that most players have difficulty defaulting to DD5.1 English, where there are
multiples available. It appears that the studio sets the default on the disc
(frequently Pro-Logic surround), and, while players support a default being set, the
studio choice usually overrides that. Very annoying.
A quick primer on some home theatre terms:
- Dolby Pro-Logic: a matrixed 4-channel surround system. The channels: Left Front, Right
Front, Center (front), and Surround, are mixed from a 2-channel program. A couple of
limitations are that the center and surround channels are not full-bandwidth (ie: center
is only ??Hz-??kHz; surround is only 100Hz-7kHz). It also supports the use of a
sub-woofer, but just feeds it information from the left and right channels. Also note that
the rear speakers (left rear and right rear) are being fed the same information.
- Dolby Digital (AC-3): a 5.1 channel discrete surround system. The 5 main channels (left
front, right front, center, left rear, right rear), and the one partial channel, LFE (low-
frequency effects) are each encoded separately. This means that the separation between
channels is necessarily better, and also means that each (main) channel can be
full-bandwidth (20-20,000 Hz). The LFE channel is always bandwidth-limited, generally to
something like 20 - 80 Hz.
- THX: stands for Tomlinson Hollison's eXperiment (sp?). It's a large program by
Lucasfilm that incorporates many elements to try to simulate a theatre experience at home.
For receivers, it consists of audio-postprocessing for setting sound levels and
delays to provide a perfect, theatre-like sound experience. For speakers, it
consists of additional electronics to allow the speakers to act as microphones as well,
which effectively allows them to set the post-processing by themselves. For
everything else (in the home), it's pretty much just a "Good Housekeeping"-type
seal of approval, saying that the manufacturing and such is up to a certain specification.
The fact that it supports VHS transfers, though, makes it a bit suspect for
software. Still, I have yet to see a bad transfer on a THX-approved disc.
Further information on home theatre THX can be found here.
- subwoofer: a low-frequency, special-purpose speaker. Generally, it has its own
power, so that the low-frequency information (largely explosions and sound effects, but
occasionally showing up via organs, double-bass, tympani, and such in music) has more
punch. The effect is pretty dramatic.
- widescreen/letterbox: A display format where the entire width of the film image is shown
on a screen. Since most TV's have a 4:3 (width:height) aspect ratio, this
necessitates black bars on the top and bottom of the image. While this does lead to
screen-space being wasted, and, hence, sometimes a bit of detail, it also means that
you're seeing the entire image that the director intended. The two alternatives to
this are called pan-and-scan and stretching.
- pan-and-scan: A display format where the image passes through a process called telecine.
Someone watches the movie, deciding which 4:3 box of the image will show up on your
television screen (eg: the left side, the right side, or somewhere in between). This
will look fine, and give as much detail as possible, but can result in things happening
off-screen that should be onscreen.
- stretching: A display format where the widescreen image is taken, and stretched
vertically. It does fill up the TV screen, but it looks quite wrong. This is,
perhaps, the most annoying format in which to watch something.
- transfer: the process of taking a 35mm (or, perhaps, 70mm) film, and turning it into a
home video presentation. It will involve choosing a display format (hopefully,
letterbox), possibly down-mixing the soundtrack, and similar things.
- aspect ratio: the ratio of the width of the viewing aperture to the height. For a
(standard definition) TV screen, this will almost always be 4:3, while for a high
definition TV, it will always be 16:9. For a movie theatre screen, standard ratios
are: 16:9, 1.85:1, 2.35:1 (and I think I've seen a couple of in-between ratios, but I
could be misremembering). A good, much longer, explanation can be found here.
- region coding: this was the big fly in the DVD ointment that kept me from looking
at the format for quite a while. Most of my laserdiscs are imported (mostly from
Japan). DVD, however, has a system called region coding that says that discs from
one region cannot be played on players from a different region. The regions I
remember are: 1, US/Canada; 2, Japan/Europe (in the same region, because Japan uses NTSC,
while Europe uses PAL, SECAM, and a couple of other formats); and 3, China.
Hollywood claims that home video releases internationally can spoil theatrical releases
domestically. Frankly, this is total BS for several reasons. One, anyone who
really wants to enjoy the film will see it in a theatre, and the presentation quality will
still be light-years higher. Two, it takes a lot of effort (and usually a lot of
money) to get the import release. If the people are will to spend the money, let
them. They've probably got a good reason for wanting to do so. Three, except
between the US, Canada, and Japan, there's a lot of variation in home video systems
used. This is not a consumer-friendly "feature".
- Macrovision: a system of encoding spurious
picture information in the video bandwidth between frames. This causes a lot of
distortion from VCR's, and mostly prevents making copies from DVD to VHS. Laserdisc,
having time-based correction, cannot offer this "feature", and, hence, remains
the format of choice for high-quality videotape copies.
Anyway, that about covers the basics. Here are some sites for buying DVD's and
Laserdiscs:
- Ken Crane's Laserdiscs. I've been dealing with
them for several years. They actually handle both formats (well), although there are now
cheaper places for DVDs.
- Reel.com. This company sprung up in the last
couple of years. They're good for DVD.
- Buy.com. This is a fairly good company for
computer equipment, consumer electronics, and DVDs.
- Amazon. I really like their book store, but
I've not bought anything else from them. They do carry DVDs, home electronics, etc.
- DVD price search. This is where you
should really start any search for DVDs on the net. They'll tell you who carries
what for how much, allowing you to do your comparison shopping in one place.
- J&R Home Audio. This is a store in NYC
that has a nice selection of equipment, generally at good to very good prices. I
think they do software (ie: CD's and DVD's) as well, but I'm not certain. They
definitely also do computer equipment.
Here are a couple of fairly random pages:
- SMR Home Theatre. They run
several fora on different topics in home theatre. They've also got a really cute page
dedicated to their cat. (Note,
though, that they seem to have a number of links that spawn separate windows... I, at
least, find this a bit annoying. YMMV, of course, but it's good to know about it in
advance.)
- Home Theater magazine. This is a
pretty good magazine dedicated to, as you might expect, home theatre. The only two
flaws of the magazine are a tendency to focus too much on very high-end systems,
and a marked tendency to really like products by companies that advertise a lot. I
suppose the former could be considered a good thing, as it does tend to give an idea of
what is likely to trickle down to the consumer level eventually, but it is sometimes a
little bit frustrating. The latter, of course, is an endemic problem in the magazine
industry, and really hard to avoid. I think I'll put some more thoughts on that here.
- Sound and Vision magazine. Home
theater's biggest competitor. Unfortunately, I don't know them as well.
- ReplayTV. This is, in essence, a digital
VCR that allows you to automatically record shows, do real-time replays, and special
effects. The idea is pretty interesting, but you do need to subscribe to their
service.
- TiVo. A competitor to ReplayTV.
And a few speaker companies.
There are also a few places with information on the HDTV standard, and about products
being manufactured (or to be manufactured):
The Criterion Collection is a
publisher of less common titles and such. They're well known, as well as respected, for
the quality of their supplements. They also do mail order via their site.
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This page created and maintained by David
Clemmer. Last modified on Jan. 12th, 2000.