also possible to have a one-to-many or many-to-many communication by
installing a reflector on another machine running the appropriate
software. The reflector software must be installed on a Unix
machine. The software can be obtained from Cornell University's CU-
SeeMe page listed in Appendix B.
Whiteboard systems also enhance audio visual conferencing. A
Whiteboard, which is analogous to a chalkboard, is physically quite
similar. Using a write-on wipe-off style of whiteboard, which has
been electronically enhanced, allows people on the Internet to share
text, drawings, and other graphic information which is being written
in real-time.
Software exists which allows connections between two sites, or
hundreds, over the Internet, the Web, or your telephone.
5.3 Archives
Archive is defined in Webster's New World Dictionary as:
n. 1 a) a place where public records, documents, etc. are kept b) a
place where material having documentary interest, as private papers,
institutional records, memorabilia, or photographs, is kept.
Archives on the Internet are pretty much the exact same thing. The
motivation and much of the content is the same, but the media changes
(from paper files, to electronic files), and as such allows for a
much greater diversity of content.
Archives on the Internet also allow many people access to their files
simultaneously, and from all over the world. Many archives on the
Internet still reside on Anonymous FTP Servers, which allow users to
log in without a user i.d. or password. When connecting to these
servers the protocol used is "ftp" the File Transfer Protocol, as
mentioned previously in Section 4.3.
Any and all information that people want to make available on the
Internet can be. This means there is a truly vast amount of
information out there, with more being added every day. In fact
there is so much information that it is sometimes difficult and
confusing to find the information you want. This is the topic of our
next section.
Some anonymous ftp sites are provided in Appendix B.
5.3.1 Searching
One of the great challenges facing the Internet is how to organize
the vast amounts of information in ways that allow most people to
find what they want. In theory, there may be a "perfect"
organization, but in practice, we will never achieve it. This means
that finding the information you want on the net may require some
skill on your part. Fortunately there are many tools and strategies
that may be helpful.
One of the all time great ideas for finding the information you want
is a thing called a search engine. A search engine is a computer
program usually living on a remote computer that spends its time
downloading information from other computers and building an index of
what lives where. This behavior has given them the nickname of Web
Crawlers. What this means to you, is that you can call up the Search
Engine's home page, and enter in a subject, name, title, or random
string pattern, which is then used to search the engines index for
stuff out on the net that seems related. This can lead to both a
large volume of information, and some rather startling discoveries of
information from unsuspected sources.
Some of the available Searchers and Indices on the Internet include:
Yahoo - Index of WWW sites, with search capabilities
http://www.yahoo.com/
DejaNews - USENET (news groups) search engine
http://www.dejanews.com/
WebCrawler - http://query.webcrawler.com/
Lycos - http://www.lycos.com/
AltaVista - WWW and USENET search engine
http://www.altavista.digital.com/
Magellan - Index of reviewed and rated Internet sites, with
search capabilities
http://www.mckinley.com/
Yahoo, for example, has a high-level category called "Arts", which
has a multitude of subcategories below it, most of which have further
subdivision, each of which can contain lists of lists.
For example, to find information on Modern Dance, from a starting
point of http://www.yahoo.com/, you can follow the links to
http://www.yahoo.com/Recreation/Dance/Modern/Groups or simply type
"Modern Dance" into the search field and choose from a list of
selections returned.
On a typical attempt on March 25, 1997, Yahoo returned 4 major
categories of Modern Dance, and offered 82 other links to related
pages around the web. Statistics, however, can be changing by the
moment.
There are many other Searchers and Indices on the Internet, and a
good way to find them, is to do a search for them in one of the
services above, or others you encounter in your travels. The
resources in Appendix B may also be helpful.
After experimenting with the available search engines, it quickly
becomes clear that searching on a broad category can result in too
much information. For example, a recent search at AltaVista for the
subject "Rembrandt" matched over 8500 individual items, including
information on the famous artist (Rembrandt von Rijn (1606-1669)),
His Self-Portrait, a hotel in Thailand (Rembrandt Hotel and Plaza,
Bangkok), and a pizza restaurant in California. (The URLs for these
sites are listed under Rembrandt in Appendix B.)
To be more particular in what you find, all of the available search
engines allow you to do compound searches, in which multiple keywords
are used, possibly in combination with Boolean logic operators such
as AND, OR, and NOT. For example, to focus in on Rembrandt the
artist, at the exclusion of pizza cafes, try the following advanced
search in Magellan:
Rembrandt AND artist AND portrait NOT pizza
Note that the method of entering search items differs slightly from
service to service. When trying a new service, check the available
help topic before searching. And as with any new skill, practice,
practice, practice!
Test of search scope:
Lycos: rembrandt. 1837 relevant documents
Lycos: rembrandt and artist and portrait 6 relevant documents
Yahoo: rembrandt 2 Category and 39 site matches
Yahoo: rembrandt and artist 2 Category and 11 site matches
AltaVista: rembrandt about "10000" documents
AltaVista: rembrandt +artist +museum about "100" documents
WebCrawler: rembrandt. 347 matching "rembrandt"
WebCrawler: rembrandt and artist and portrait 21 matching documents
Magellan: rembrandt 666 results
Magellan: rembrandt and artist and portrait 39379 results
You will notice, in the above statistics, that the numbers for
Magellan are quite different from the others. This is because
different search engines may function differently. When you do a
this+that search on Magellan, it looks for all instances of This AND
all instances of That rather than the standard response of Only
documents which contain both This AND That. On almost all the sites
I have explored, there is an explanation of how the search process
works on that site. You should read that explanation if you are
having trouble or need further information.
You will also begin to see patterns in the way people name, or file,
their information, which will help you find more information. Some
may list their links to ART, while others list their links to
PAINTINGS. Also many people put links to related pages in their
pages, so one page you find that does not have what you are looking
for, may have a pointer to another page that does have what you are
looking for. Searching is an iterative process, keep going from one
search key to another, and continue down multiple levels to see what
is out there. Its known as Exploring, or Surfing the Net, and it is
a major part of the joy of the Internet.
6. Accessing the Internet
Having decided to explore the Internet, you will need some tools and
information to get you started.
Accessing the Internet in terms of simply receiving, downloading, and
viewing files, uses most of the same tools (software and hardware)
needed to create files and make them available on the Internet.
Sections 6 and 7 overlap a great deal in the areas of basic hardware
and software.
The Internet can be accessed in many comfortable ways: at school, at
home, at work, and even at trendy CyberCoffeeHouses. Accessing the
Internet is not synonymous with publishing and displaying on the
Internet, however. You may need different equipment for creating
content, then you need for retrieving content. Section 6 focuses on
the specific needs of those who wish to create content and publish on
the Internet.
If you live near a major metropolitan area you may have already begun
to see advertising for Internet access from your local telephone
company, or cable TV provider. Contact them to get information on
equipment needed, services provided, access restrictions and costs
involved.
Local libraries and schools may now offer both Internet Access, and
instruction on Internet related subjects, including getting
connected. Check the Internet sections of your bookstore and
magazine stands.
Do not be dissuaded if you find limited access. The Internet will
soon be everywhere, but if you do not want to wait, then you might
consider taking matters into your own hands as these enterprising
youths did...
When several students from large universities returned home to
Taos, NM, a few summers ago, they left behind their Internet
connections. Missing their connectivity, they approached the
owner of a local bakery and suggested he start an Internet room
where he could charge people by the hour to use the Internet. The
entrepreneurial baker applied for a government grant and received
a few computers with high speed modems.
You may be able to find a place like this, often called a CyberCafe,
rather than having to create one. Try your local magazine stand for
the latest periodicals, or your public library or bookstore for
pointers to other people who will know more.
Once you have some Internet access, you can find out more about
Cybercafes, InternetCafes, and other physical Internet access points,
by searching as described in Section 5.3.1. and in the newsgroup
alt.cybercafes.
6.1 Internet Service Providers
Being an Internet Service Provider (ISP) these days is pretty easy
and can be financially worthwhile, so there are alot of them, and
they are starting and failing every day. In addition to the
information and pointers you will find in this document, many
organizations exist to help you locate, and choose a service
provider.
As with any service, be sure to get references, and get their
features and terms in writing. Some ISPs provide access only to
their site, others may provide email only, or provide access to the
web but charge by the minute for access. Have some idea of what you
want to do and what the vendor provides before making any deals.
Many Internet Service Providers offer free instruction to get you
started in accessing the Internet as well as creating content. With
the competition of Internet providers, you should be able to find one
or two that offer the instruction you need.
Some organizations exist solely to recommend those who pay them.
Most Internet related magazines these days will contain extensive
advertising by ISPs in your area.
As discussed in Section 4.1, every machine on the Internet needs an
address by which it is accessed. Even machines which are only
browsing need an address to which the browsed information is
returned. This is actually called your IP address. The address is
the number with which your hostname is associated. Usually you will
get your IP address from your work, school, or ISP when you get your
configuration information for your Internet connection. If you were
trying to get an IP Address on your own, you would go to the Internet
Assigned Numbers Authority (IANA).
More information about IANA, IP addresses, and domain names can be
found in the information referenced in the Resources section.
6.2 Computer Hardware and Software Tools
A basic computer system consists of a box containing a Central
Processor Unit (CPU), main controller (motherboard), and Floppy
Drive. It will also come with a keyboard, and you will need a Hard
Drive, Memory, and a Video Monitor. How much memory, how large a
hard drive, and how fabulous a monitor, will vary with your needs and
experience. To connect to an ISP you will usually also need a modem.
This is simply an overview to familiarize you with some basic terms.
There are many current magazines devoted to computer and Internet
related subjects now available in most bookstores and magazine stands
which provide much better and more timely information on computers,
operating systems, software, and peripherals.
There are many types of computers available including Personal
Computers (PCs), Apple Macintosh Computers (Macs), and various Unix
based Workstations. The most affordable systems are generally PCs
and Macs.
You may also need to choose an Operating System (OS) for the machine
you choose. PCs can run a version of "DOS", anything from Microsoft
(Windows, NT, Windows95, etc.), or a version of Unix (BSDI, FreeBSD,
Linux, etc.) Macs can run the common Mac Windows, or Apples version
of Unix. Workstations generally run a Unix derived OS, but there are
also quite a few machines available which run their own proprietary
OS.
Each type of system has its features, functions, and drawbacks, as
well as its proponents and opponents. Each system has different
costs associated with it. You will need to understand much of this
before you are ready to buy your first computer. Much of the free
software available on the Internet, for example, was written for the
Unix operating system because that has been the main OS of the
Internet for many years. That, of course, doesn't mean there isn't
alot of free software available for other OSs, Windows software, for
example, is becoming quite popular. The system of choice for most
musicians is the Mac because of the variety and quality of the music
software available for them. Windows users will need a pc to run
their software. Now, actually, there are many operating systems
available for personal computers.
Common operating systems come in two basic types; single tasking and
multi-tasking. This is a reference to how many different things or
"tasks" the computer "seems" to be doing at once. The earliest
computers were single tasking. They did only one thing at a time,
and could be used by only one person at a time. DOS is a modern
example of a single tasking operating system. Since people rarely do
more than a few things every second, this often left the computer
simply waiting around for the next keystroke.
Even back then, computers could do all the work needed to listen to a
human in a few milliseconds every second, so time-slicing was
invented to get more use out of computers.
A time-slicing operating system is said to be Multi-tasking. It
executes programs in little slices of time, typically shorter than 25
milliseconds (or 1/40 of a second) and switches to another task for
each new slice. If you remember that most video runs at 25 or 30
discrete frames per second, and yet humans perceive it as continuous,
you can see how time-slicing can provide a convincing illusion of
doing many things at the same time.
Multi-tasking operating systems have the option of being set up as
single-user or Multi-user machines Windows 95 and the MacOS are
modern examples of multi-tasking operating systems that were designed
to be used by a single user most of the time. Other operating
systems, such as UNIX, VMS, NT, and others are more prepared to be
set up as multiuser machines. Multiuser machines are typically
connected to a network, or a network of terminals, so that more than
one person can use the processor and other peripherals at the same
time.
Some operating systems can also take advantage of Parallel Processing
hardware that actually does more than one thing at a time. However
as of this writing, this hardware is somewhat rare and expensive, so
we won't go into the details here.
Different OSs also have different File Systems. The File System is
the way in which your programs and other computer files are stored
and displayed. Different Operating Systems also have different "User
Interface"s. The User Interface is the way in which you interact
with the computers OS. Some use "Text" interfaces, which require the
user to type all commands using a keyboard. Others use a "Graphical"
user interface, which provides graphical images of buttons and icons
which the user "clicks" on to start programs and perform save and
delete functions among other things.
In order for the software to run on the computer, the software must
be written specifically for the operating system. Just like Internet
traffic must use the Internet Protocol, software must speak the OS
language of the computer on which it wants to run. Translation
programs exist, but there are still problems.
One of the problems is with file"names". The DOS Operating System,
for example, supports names that consist of an 8-character filename,
and a 3-character "extension", separated by a ".". For example
"foo.txt", and "myprog.exe" are valid DOS filenames, but sadly,
"foo.html" is not. This means that HTML files on a dos system must
use the extension ".htm" rather than the ".html" extension used on
many other systems. This problem also affects many other common
extensions such as ".jpeg", ".mpeg" and others.
A filename's extension is very important in that it tells not only
you, but your software, the kind of file it is, and what it needs in
order to be understood. For example, when your web browser
encounters a file with a .html or .htm extension, it will assume it
is hypertext, and will know how to display it and follow its links.
When it gets a .txt file, it knows to display it, and that it will
have no links. Your browser can also be configured to understand
other file formats which can be made to be displayed with the
browser, or another program, or saved to disk, etc. For example, you
might configure your browser to start up Word when it encounters a
.doc file.
File extensions indicate file format. Just as there are different
file extensions for different text file formats, there are different
extensions for different graphic file formats. That goes for sound
file formats, video file formats, data base files, and others.
Different software understands different file formats and will create
and display only those formats it understands. For this reason,
software which translates a file from one format to another is often
necessary.
For example, if you create a file with Microsoft Word you will
usually save it in Word's native format as a ".doc" file. You can
also choose the "save as" option to save it as plain text in the .txt
file format. Although some format information will be lost in the
translation, words and numbers should remain unchanged. If you
wanted to give others access to the file, and you couldn't assume
that they all have Word, you would want to present it in .txt format.
Note that a .txt file is also easily formatted into .html.
File formats and extensions are discussed throughout the following
sections.
After you've resolved to some extent, what it is you want to do, and
what hardware and OS you'll need, there are a great deal of software
packages available to help you with all sorts of things on the
computer.
Software designed to make your life easier by using your computer,
include dictionaries and other reference materials, accounting,
bookkeeping desktop publishing and other business needs software, as
well as landscape and architectural planning software, health and
nutrition software, educational and entertainment software, and much,
much more. Your computer need not only be your link to the world,
but also a major organizational tool in your life.
For accessing the Internet, you'll need communication software.
There are a few different pieces to this part of the puzzle. There
is the software which communicates between the operating system and
the modem or network card, there's the software which speaks IP and
allows communication over the Internet, and there's the software
which you use which is called the "user interface", or application
program. For accessing the web, your application will be a "web
browser".
Web browsers are available in stores that sell software packages, and
are also available free on the Internet. Since you would not be able
to reference the online material without a browser, and since most
available periodicals will be likely to focus on commercial browsers,
the Resources section provides a pointer to a free browser available
by mail for the cost of postage, or over the Internet using the File
Transfer Protocol, FTP.
Ftp software is available both free and commercially. Other Internet
communication software, referenced throughout this document, are
email, news, gopher, and telnet among others.
With any system, you should ensure that it contains the software and
hardware necessary to maintain both itself and your data. While
computer data is not particularly fragile, it is still sometimes lost
due to hardware or software problems or simple human error. For this
reason it is considered important to "back up" your system by making
extra copies of important data. While simply copying data onto
floppy disks could work, the small storage size of the disks makes it
both time consuming and prone to human error. Many large capacity
disk and tape drives are available with special software specifically
for doing backups. It is highly recommended that you purchase a
backup solution along with your computer.
It is also important to protect your data from being damaged by
computer viruses. When you connect to the net and move data back and
forth, it is possible that there can be a small piece of software
called a "virus" that could hide in some of the data and infect your
system, possibly then using your system to infect other machines that
you connect to. These viruses are often created by misguided people
as a sort of computer prank, and can accidentally or maliciously
damage your data. Fortunately it is possible to obtain virus
checking software that can regularly scan your system to see if it
has been infected. This software is important whether you are
downloading information from the net, or using other peoples floppy
disks. See Section 8.2 for more information on viruses.
Determining your ideal hardware and software configuration will take
some time and patience. You need an understanding of what you want
to do, and how, and whether you wish to simply view, or create.
You'll also want to know the limitations and expandability potential
of the system, so you can determine if it will have a useful
lifespan. If the machine cannot grow for the foreseeable few years,
it will become obsolete before its given you its fullest value.
6.3 Multimedia
When one media is not enough.
Depending upon your needs, you may require special hardware installed
in the machine, or attached externally by cables. These additional
pieces of hardware are known as peripherals.
The peripherals needed for accessing information on the Internet
might include the following:
- a sound card and speakers to hear sounds, music, speech, etc.
- a CD-ROM player to read commercially available computer CDs
- midi equipment for audio artists
- video equipment
- a printer to make hardcopy of files, or images
- Other equipment for creating content See Section 7.
Most of these peripherals will also require specialized software. If
you plan to purchase all the hardware and software at once, find a
vendor who will connect and test all the hardware, software, and
peripherals for you. Due to the complexity of these systems, they
can be difficult to configure for the inexperienced user.
Also, verify that the vendor will stand behind their equipment, and
this configuration in the event that it doesn't work the way you want
it to. Hook the system up, and test it extensively right away, so as
to determine any problems before your warrantee period expires.
Many of the Internet related periodicals available run articles on
choosing a computer, as well as the latest software and hardware news
and reviews.
You can also explore the pointers in Appendix B for the information
you need.
7. Creating Content
As the hardware and software of the net becomes cheaper and better
understood, the technology itself will become less important than the
content which lives on the net. Many of the rewards of the Internet
will go to the people who create such content.
There are different ways to add content to the Internet. One may
start with pre-existing content, such as paintings or stories, and
find a place for it, or one may create content specifically for the
computer such as web pages, graphics, video and audio files, etc.
Let us for the moment assume that you have already created something
which you would like to make available on the net. There are many
ways in which you could do this. You could deal with agencies who
provide this service professionally, find friends or others willing
to do it for free or barter, or get yourself on the net in some
fashion, learn, and create a place for it yourself.
If you chose to do it yourself, you will need your own computer and
some form of Internet access from an Internet Service Provider (ISP)
or Web Space Provider (WSP).
Once you have a place to put your content, you will need to
understand a little more about file formats. Images may have to be
digitized, audio may have to be recorded into computer files, etc.
While hardware, such as image scanners, are readily available, there
are also many other options available. For example, most print, or
copy shops today can do high quality image scans and some photolabs
now provide photos-on-disk as one of their services.
If you are placing your content on the Web, a web page must be
created for it in the form of an HTML document. While this is easy
enough to do yourself, many WSPs also offer this service, and there
are also independent web page designers who may be able to do a
better job.
Creating online content involves moving your art into an electronic
form and then perhaps, re-formatting it for the Internet. For some
art forms, the initial electronic step is fairly painless: typing a
short story, poem, novel, or other text into HTML is fairly
straight forward. Moving a computer graphic to the Internet may
require a conversion program to make it useful to others. Performing
arts, sculpture, and other pieces may be more difficult to capture on
a computer disk, and may require more work and creative thinking.
Much of the information needed to help you think creatively about
publicizing your work online is available in classes, books, local
Internet cafes, and on the Internet itself. Many Internet magazines
are available for subscriptions or individual issues can help get you
started. Most new bookstores and, to some extent, used bookstores
provide numerous volumes of Internet information. However, even the
most recently published books may contain outdated information. The
latest 'standards' can be obtained directly from the Internet
Engineering Task Force, or IETF, at http://www.ietf.org/. The
document you are reading now is a product of that organization. The
documents of the IETF are collected and maintained on anonymous ftp
sites, as well as in the web. These sites are referenced in the
Resources section, and Appendix B.
A really good way to learn how to write html documents is to look at
the source code of html files already available. Just use your
browser to look for pages you like, and then use your browsers "view
source" feature to see how it was done.
If however, you learn better by having someone teach you, you may be
interested in taking a HTML or Internet Introduction course at a
local college. Most larger metropolitan area schools provide classes
for the basics, which can also expose you to other artists. Make
sure you read the course description; some courses may only cover
accessing the Internet while you may want to actually be creating
documents. If no colleges in your area offer classes, contact the
computer science department or the continuing education office and
suggest a topic. If the school can obtain enough support, they may
offer a class the following semester.
Artists in smaller communities may need to rely more heavily upon
online sources of information. Appendix B provides some useful sites
to get you started.
7.1 Getting Help
Once you are connected to the Internet, there are many more ways of
getting help with it. Try the forums, listed in Section 5, such as
Newsgroups, Bulletin Boards, and Chat rooms. If you have checked the
local netiquette guidelines, and behave accordingly, the Internet
community will usually be very helpful toward new arrivals.
When looking for good consultants and web page designers, start with
the sites you like, and find out who did their pages. Discuss your
needs with other artists, or check the phone book, library, books,
magazines and other periodicals for artist collectives and groups who
may be available to assist you. Look for groups whose cause is
artistically motivated, rather than trusting people who are paid to
point you at a particular consultant or assistant.
Know what you want. If it takes you a while to figure out what you
want, take that time. This should not be something you are rushed
into. The Internet is not going to go away. Whatever you decide to
do, do not be afraid to ask for references. A good provider of
services will always be happy to provide you with a list of happy
customers.
7.2 About File Formats
As described in Section 6.2, there are many file formats available on
the Internet. You'll need to understand a bit more about the formats
you'll want to present, in order to create them for others to see.
Some formats are called Public Domain, and are freely copyable, and
the software tools used to create this content is available for you
and others to download off the net. Other formats are called
"proprietary", and are only readable and creatable using software
that must be purchased from the vendor who created it, or their
authorized reseller.
Some formats, and their associated formatting tools, come along with
other software packages. For example, Microsoft Windows comes with a
Sound Recorder, which makes and plays back .wav files. Apple also
offers Quicktime free for their OS, as well as Windows and others,
which also records and plays back .wav files. So many Internet
explorers already have access to tools which will allow them to hear
your .wav file, if you were so inclined. They may not, however, have
a player for a proprietary format for which they would need special
software.
When creating content for the Internet, its important to consider the
format most likely to be understood by your target audience.
More information on file formats can be found at:
http://www.matisse.net/files/formats.html and
http://rodent.lib.rochester.edu/multimed/contents.htm
Some artists are actually using html as an artform in itself and are
helping to push the boundaries of this exciting new medium. The
current HTML specification can be found in the RFCs referenced in the
Resources section.
7.3 Creating Text and Hypertext Documents
Text files are stored on a computer by encoding the text in ASCII,
"American Standard Code for Information Interchange", which
substitutes a distinct number for each character of text, and stores
the result in a file. Text files are often given the file extension
".txt".
Text files can be created in many ways. The two most common types of
programs used are called "text editors" and "word processors".
Actually both types of programs are similar. They both allow you to
move around within the document, and add, delete, and otherwise
modify text, as well as create and save text files. Word processors
differ from text editors in that they usually also have a great deal
of options for formatting and printing text, and may support
alternative file formats, such as ".doc" which inserts many
formatting commands that are understood by printers, but not always
by browsers.
Since HTML formatting is simply ASCII text with special formatting
commands, you may use either text editors or word processors to
create a ".html" file. Alternatively, there are many Web authoring
tools that will allow you to use a graphical interface to specify how
you want your page to look, and will automatically generate the HTML
formatting commands and output an ".html" file directly.
Text editors, Word Processors, and other document creation tools are
available both freely and commercially for all operating systems.
Look to currently available computer related books and periodicals to
provide sources of information about text editors, word processors,
and document and web page authoring tools.
HTML is a technical specification of the Internet Engineering Task
Force, and the most current documents can be found on the IETF
site(s) listed in the Resources Section.
7.4 Creating Graphic and Moving Images
Whether you want to put your existing images on the Internet, or
create new images using electronic creation tools, there are a few
basic pieces of information which will be useful. The following two
sub-sections provide an overview of image formats, and creation
tools.
7.4.1 Bitmap Image Formats
Pictures may be stored on computers in many different ways. One of
the most common, is a simple bitmap consisting of a list of pixel
colors, and header information describing how to map this list of
pixels back into the image. Bitmap formats are .bmp in windows, and
Bitmap images may be created by scanning in existing images, or by
creating images directly on the computer, using programs such as
Adobe Photoshop, Corel Photo Paint, Windows Paintbrush, and many
others available both freely and commercially.
A scanner works very much like a copy machine, or fax machine, in
that it "scans" your artwork or text and "encodes" it into a machine
readable format of numbers and formulas. A scanner is a hardware
tool, and usually comes with at least some of the software you need
to use it. Generally it will connect to your computer and you will
either place your work on it, or run the scanner slowly over your
work, depending on the type of scanner you select. Scanners are only
available commercially, and come in a variety of sizes and styles
with a variety of features and prices. As with all computer tools,
understanding what you want to accomplish will help you decide what
you need to purchase.
Since it can take a lot of data to encode an image, there are many
different kinds of file formats that contain compressed versions of
the file data. These formats vary greatly in how they compress the
data. Two of the most popular compressed image formats on the net
are .gif and .jpg.
GIF, short for Graphic Image Format, compresses an image by reducing
the number of colors in the palette the image is reconstructed from,
allowing them to shrink down the size of the color specification for
each pixel. Even if you only save a few bits per pixel, there are
typically enough pixels that the savings are significant. Under
extreme amounts of compression, images start to look like childrens
coloring books, but it is possible to get great looking images with
moderate amounts. GIF files typically use the extension ".gif".
The JPEG format uses complex mathematics to approximate the whole
image. Under extreme amounts of compression, images start to look
like bizarre cubist interpretations of the original image, but
because everything about the image is compressed, it is still
possible to get dramatic reductions in file size while retaining
acceptable image quality. JPEG files typically use the extensions
".jpeg" or ".jpg"
Both of these formats are what is known as "lossy" compression
because they actually lose information from the original image, thus
degrading (hopefully by a negligible amount) the image quality.
There are also "lossless" compression schemes that offer smaller
reductions in file size, but allow perfect reconstruction of the
image.
7.4.2 Vector Image Formats
Another way images may be stored is in "vector" format. This format
is useful because of one of the techniques for creating images on a
computer. There are programs that allow you to create images by
creating shapes like circles and polygons, and specifying colors for
them. If the entire image is constructed this way, it is possible to
encode the list of information describing each polygon using only a
fraction of the information it would take to describe each pixel.
Vector images also have the wonderful quality that they may be scaled
without loss of image quality. For example, if you were to enlarge a
bitmap image of a circle large enough to see individual pixels, you
will find that pixels are actually square dots, and if enlarged
enough, the circle will have very jagged edges. However if you
enlarge a vector image of a circle, it remains perfect down to the
limit of resolution of the screen or printer, because it is stored as
the mathematical representation of a circle which is independent of
scale.
For this reason, much commercial art and layout is often done in
vector formats.
Vector formats may be created using many commercially available
software packages, and many freely copyable conversion tools are also
available.
7.4.3 Video Formats
Images received by the retina of the eye persist for a short period
of time, and then fade. A sequence of images or "frames", with small
changes, sufficiently close together, will give the illusion of a
moving picture. How much of the picture changes between one image
and the next affects how smoothly or jerkily the movement will
appear. Frame rates of 10 per second and above are enough to give a
reasonably realistic rendition of natural scenes. In fact, the way
that motion is perceived by the human brain means that less detail is
required in fast moving segments of a picture.
Video on your television, or Video Cassette Recorder (VCR), is
formatted quite differently from video formatted for viewing,
storage, and transmission over the Internet. Disk space and
bandwidth being constantly at a premium, methods of compressing video
data have been developed to shrink the size these video files might
otherwise be.
Just as described in Section 7.4.1. regarding compression of static
images, there are different compression utilities and formats for
video images. There are many video compression formats, and we have
provided information on two here.
MPEG (pronounced M-peg), stands for Moving Picture Experts Group.
The mpeg format creates files with a .mpg or .mpeg extension. Mpeg
players are freely available on the Internet. Mpeg files can be
created using a number of commercially available products. More
information on mpeg can be found by following the links available in
Appendix B under Video Resources.
Quicktime was created by Apple, and is currently available for both
Macintosh and Windows systems. Quicktime files have a .wav extension
and can be played with many freely available viewers. Quicktime
creation and viewing tools can be found via the links in Appendix B.
There are other video formats being created all the time.
7.5 Music and Sound
The World Wide Web supports audio data as well as visual data. The
most obvious way to send audio across the net would be to use digital
audio like that used for the Compact Disc or "CD". However, CD
format digital audio requires 44,100 16 bit words per second for a
mono signal, and twice that for a stereo signal. While there are
many places where one can find digital audio in Windows ".wav", or
the Macintosh ".au" format, these files typically take a very long
time to download even a few seconds of audio. The size of these
formats makes them too inefficient for widespread use on the net
today.
It is however possible to do "useful" audio over the net. The
emerging "de facto" standard seems to be _RealAudio_, based on the
freely distributable server/player application, _RealAudio_ version
2.0, developed by the Seattle based company Progressive Networks.
First released in 1995, RealAudio allows useable digital audio in
realtime over a 28.8 kB line, and has already been put into service
on the home pages of most major record companies as well as in many
niche applications. In addition, RealAudio provides a "Voice mode"
optimized for understandable speech transmission over a 14.4kB line.
Unfortunately the quality of _RealAudio_ leaves much to be desired.
In particular, the sample rate in Music Mode is only 8Khz (as
compared to CD quality 44.1 Khz), meaning that all high frequencies
above 4khz are simply missing. The resulting audio is still pleasing
to listen to, but sounds very dull and dark.
More information about RealAudio can be found at www.RealAudio.com.
Clearly Digital Audio is the way of the future, but until more
bandwidth is available to the average person, it may not be the way
of the present. Fortunately, at least in the area of music, there is
an interesting alternative.
MIDI (the Musical Instrument Digital Interface), as developed for
electronic musical instruments (keyboards, samplers, drum machines,
etc.) works well for certain kinds of music over the net. It
involves sending no sound sources at all, just the description of the
music -- kind of like the score, without the instruments. If the
receiver has the right instruments on their computer (such as the
sounds defined in the General Midi soundset found on many
soundcards), they can play back the musical score.
The big disadvantage to using MIDI is that other than the limited
selection of sounds in the General Midi set, it is extremely
difficult to make sure the music sounds more than approximately like
the original. And there is no way to handle non-MIDI instruments
such as guitar or voice, so it is useless to hear the new song by
your favorite rock and roll band.
The big advantage to MIDI is how fast it works over slow net
connections. For example, five minutes of music, fits in a mere 30k
file, and usually will not take more than a few seconds even on the
slowest of dialup connections! This makes it ideal for applications
such as networked games, or music to go along with a web page.
There are many ways of embedding MIDI files into HTML documents, for
Internet distribution.
Anyone who wants to add MIDI to a page can choose to use existing
public access MIDI file banks, of which there are many, or to produce
new MIDI themselves.
Crescendo is one package available for embedding MIDI files in HTML
http://www.liveupdate.com Crescendo works for both Macintosh and
Windows.
Helpful Links: Publicly Available Audio and Music Applications
http://reality.sgi.com/employees/cook/audio.apps/public.html
Music of J.S. Bach for keyboard
ftp://ftp.cs.ruu.nl/pub/MIDI/SONGS/CLASSICAL/BACH/HARPSICHORD/
RISM (repertoire of manuscript sources), plus other access to online
scholarly music resources. http://rism.harvard.edu/RISM/
Crescendo is used in the web pages at http://mcentury.citi.doc.ca
along with a growing number of others. One very interesting use of
Crescendo occurs on the Music Theory Online publication, a serious
scholarly site for publishing and debating musicology and music
theory. Articles there now routinely include short musical examples,
a great sign of the future of scholarly publishing in the age of
dynamic, interactive content.
http://boethius.music.ucsb.edu/mto/issues/mto.96.2.4/
Formerly, debate on musical form and structure occurred in the pages
of journals, referring usually to music examples in terms of its
visual notation. This notation requires a certain degree of training
to decode, effectively restricting the potential readership to those
with this professional training. With sound examples embedded
directly in the text, at least the aural effect of the music comes
across, even to those unable to read the notation accurately. This
shift is appropriate to the newer trends in music scholarship, which
talk about music in terms of its social and cultural context, instead
of only in formal terms.
7.6 Content Design Issues
Know your intended audience. If you want more people to see your
work, you'll need to make it more accessible.
Many sites are very careful about what content they will allow access
to. If you want all audiences to be able to view your work, make
sure you are careful about your content and language.
Another content design issue is tool friendliness. Some machines
have limitations which will not allow them to see or hear what you'd
like them to. For example, older or less expensive models of
monitors may have monochrome, or one-color displays, or display only
16 colors, or 256 colors. If you create and view images which look
fabulous with a 64,000 color display, you may want to test them using
a 16 color display to see what the effect is. Sometimes you can
modify your image slightly to get a wider audience while only having
a minor impact on the effect.
The following sites give you pointers on what to consider when
designing a web page that is content- rich:
- Sun's Guide to Web Style - http://www.sun.com/styleguide/
- Yale C/AIM Web Style Guide - http://info.med.yale.edu/caim/manual/
- Web Development - http://www.december.com/web/develop.html
- A Guide to Creating a Successful Web Site =
http://www.hooked.net/~larrylin/web.htm
- Bandwidth Conservation Society - http://www.infohiway.com/faster/
This is resource for web developers with an interest in optimizing
performance.
See Section 8 for other issues and challenges relating to content.
Artists should post how they want their art treated on the web, and
how it may be used and post their copyright notice there.
For example, some artists allow their work to be used freely as long
as it is not used for financial gain, and request that people contact
them for permission if they wish to use their works for a commercial
purpose.
Artists need to be aware that when people view their works from the