Chapter 3: Hamming It Up for the Webcam In This Chapter Broadcasting from your rec room Looking at webcam’s hardware and software sides Adding an external webcam to a laptop Artist A
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Regularly update your Web browser with current versions of video enhancements such as Java Some web sites warn you if the necessary software isn’t found on your machine, and then direct you to install it
✦ A broadband Internet connection, such as one received via a cable modem, fiber-optic signal, or DSL connection; your computer may
be directly connected to the incoming feed with an Ethernet cable or may be indirectly connected — at a slightly slower speed — through
a WiFi wireless link (Dial-up telephone connections are no longer worth considering when it comes to working with Internet media.)
✦ A sound card or built-in sound processing circuitry on your laptop’s motherboard
✦ A decent set of speakers, either built-in or external
Radio days
Think way back to the early days of radio, like the 1880s when German physicist Heinrich Hertz performed his research on electromagnetic radiation (called at the time aetheric waves or Hertzian waves, and now more commonly known as radio waves) Jump forward a few decades and consider the practical implemen-tation of many of those ideas by Italian-American inventor and businessman Guglielmo Marconi, who began his experiments in Europe and then crossed the channel to Canada and then America
By 1904, Marconi had a small commercial service that communicated with ships at sea, and in 1912 the S.S Titanic had company-trained telegraphers aboard the ship on its maiden (and only) voyage One of Marconi’s employees — involved with monitoring the rescue efforts for the Titanic — was a young man named David Sarnoff, who went on to pioneer commercial radio at the Radio Corporation of America (RCA), the forerunner of today’s NBC network
What’s the thread here? Hertz was sending a signal from a single transmitter to a single receiver; even though the process is a lot more complex today, essentially that happens when you communicate by Instant Message (IM) from one computer to another — the information isn’t meant to be shared with others
Marconi began his work with sending a signal to and from an identified group of clients — ships
at sea and land-based stations That’s similar to what you might call narrowcasting The infor-mation is out there and available, but not intended for the public at large
And then Sarnoff helped launch what you now know as the broadcast industry From one source — a network at first — a signal is sent into the ether for anyone and everyone to receive and use From NBC came “Fibber McGee and Molly” and “Burns and Allen” and other early megahits of radio
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✦ A video adapter, video memory, and a video processor capable of
generating a high-resolution moving image
✦ A high-resolution LCD to show the image
✦ A full-strength, up-to-date firewall and antivirus program (discussed
in detail in Book IX) Anytime you open a door between your computer and the outside world (especially if you leave it open for an extended period, as when you’re accepting a continuous stream of information) you expose your machine to infiltration attempts by mischief makers and evildoers
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Trang 4Chapter 3: Hamming It Up for the Webcam
In This Chapter
Broadcasting from your rec room
Looking at webcam’s hardware and software sides
Adding an external webcam to a laptop
Artist Andy Warhol entered the book of famous quotations in the 1960s when he somehow looked into the 21st century and said, “In the future everyone will be famous for fifteen minutes.”
How in the world did he imagine YouTube, streaming video feeds from net-work television, and the fact that I can sit here at my laptop and smile for the webcam built into frame above the LCD and narrowcast myself from here on
my little island to anywhere in the world capable of receiving a broadband Internet signal? I can be famous for fifteen minutes or all the time
Other than self-aggrandizement and inflation of my ego, what purpose does
a web camera (webcam) serve?
✦ Recording an audio and video e-mail to send to family (Remember how
Dr Heywood Floyd kept in touch with his wife and daughter back home
on earth in the classic film, 2001: A Space Odyssey? Just like that Only
from your den to your mother’s kitchen.)
✦ Producing your own sales pitch, instructional video, or personalized message for a business client or prospect (Here, let me show you how great our pearl-inlay sushi knife cuts through the Buffalo phone book in one slice.)
✦ Starring in your own entertainment/political manifesto/ego trip of a video to post on a website that tells all sorts of unimaginably personal details available to anyone and everyone in the world to see
✦ Posting your own travelogue based on videos and still pictures taken with your camera, cell phone, or even the laptop itself
✦ Peeking into your home or office while you’re somewhere else in the world Is the dog on the sofa again?
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Casting about for Hardware
You must have three essentials before you can send video from your laptop:
✦ A webcam It can be built into the computer itself, as is the case with
this book’s demonstration machine, the Toshiba Satellite P205, which has a 1.3 megapixel camera installed in the LCD’s upper frame See Figure 3-1 Or you can purchase a separate camera that attaches to your laptop through the USB port; you may set up the camera to clip on to the top or side of the LCD or you may sit it by itself on your desktop
✦ A broadband Internet connection Video, whether streamed live or
transmitted as a file, demands a great deal of space on the hard disk or
on the Internet connection
✦ Software to control the camera Sophisticated applications adjust the
brightness and contrast, sharpen the image, perfect the colors, and package up the results for streaming to the World Wide Web or attaching
to an e-mail
If you really want to get fancy about it, you can also add a video-editing suite that lets you carve up video shots with your webcam — or from any other video source — and edit it into a mini movie
Camera Assistant Software
In this chapter I use as an example product called Camera Assistant Software (CAS), which is a capable generic program supplied by Toshiba to support the built-in webcam (made by Chicony) in many of its current laptops Other camera and software combinations work in a similar fashion
You can launch the CAS toolbar from the taskbar, or (in its default configura-tion) have it lurk just off the left side of the LCD; just hover your onscreen pointer in its home area and it appears, ready to open the camera lens and apply other controls to its use
You can drag the toolbar to another location onscreen or assign menu options
to a specific location at top, left, or right Right-click the toolbar to display
an Auto Hide option to keep the controls out of the way anytime you aren’t using them
The following CAS options appear similarly in most other basic camera-control programs
Preview
Start Camera turns on the video system; you see a preview image on your screen The video isn’t being recorded or streamed at this point
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Effects
Apply some special pictures and icons to your video with Effects Want to include a Valentine’s heart, a bouquet of roses, or a big red set of lips? Like
to add a filigreed or flowery frame to the image? These effects and others are offered here
Properties
In CAS, you can adjust the lens zoom between normal, or 100 percent, and
400 percent (4X)
In Figure 3-1 you see the lens as the tiny bright spot at the top of the LCD frame On the laptop screen you can see me poking my digital camera through the light tent in my studio to photograph the computer photographing me
Figure 3-1:
I turned on the built-in webcam in the Toshiba Satellite P205 laptop
Zoom a zoom zoom
Four-hundred percent (4X) zoom is called a dig-ital zoom and is made by cropping a section of the image sensor and electronically enlarging the picture — it’s not as sharp or clear as the
result you get from an optical zoom that uses an adjustable lens, but then again, you’re working with a tiny camera-on-a-chip not much bigger than a pinhead
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Other options include the ability to horizontally flip an image — removing the mirror effect you see when you look at a screen that shows the image through the camera lens You can also flip an image vertically; somewhere out there is a problem for which that’s the solution
You can compensate for flicker in an image caused by slight differences in electrical systems around the world In North America and most of the rest
of the world, power alternates 60 times per second, also called 60 hertz or 60 Hz; if you’re in one of the few places that use 50 Hz, you might experiment with changing this setting
Adjusting the flicker setting compensates for the changes in lighting caused
by light bulbs running on alternating current (AC), including fluorescent bulbs; the laptop itself is running on direct current (DC) power provided by its adapter
Some camera software programs can pan the image slightly to the left or
right or up or down You can, of course, accomplish pretty much the same thing by moving the laptop on your desk or adjusting the angle of the LCD screen with a built-in camera
CAS also includes a night mode that boosts the exposure levels for dim lighting (although the pictures are of lower quality) and a backlight com-pensation setting
Settings
CA’s advanced options let you adjust the quality of digital snapshots, video, and audio captured through built-in or attached devices See Figure 3-2 In general, you want to use the highest resolution for pictures, the fastest frame rate for video, and the highest sampling rate for audio However, you must consider several issues:
✦ You can’t capture images or audio at qualities greater than the CA hard-ware’s capabilities Cameras are limited by the resolution and sensitivity
of the image sensor, as well as the quality of the tiny lens, while you can’t compare the quality of the small microphone to a sophisticated studio recording device
✦ The frame rate for video and the compression rate for audio or video is related to the speed of the laptop’s microprocessor and available RAM
✦ The type of file formats supported are set by the designers of the control software
✦ Files created using the highest resolution, frame rate, or sampling rate
and a file format that doesn’t compress are going to be significantly
larger, compared to lower-quality selections
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As an example, the CAS program on this book’s sample Toshiba laptop allows picture capture at a resolution as high as 1280 ×1024 — equivalent to about 1.3 megapixels of information At the low end, you can capture images at a setting of 160 ×120, which may only be appropriate for uses such as a back-ground image for a cell phone CAS permits storage of still photos as com-pressed JPEG files, PNG files (which use a lossless compression scheme), as well as uncompressed BMP bitmaps
A lossless compression scheme promises to reduce the size of the file
with-out causing any degradation in the quality of the image; compare this to a
lossy compression which may result in some loss of quality If you save a file
in a lossy compression style, such as JPEG, and then reopen the file for fur-ther editing, the quality will continue to degrade each time you save the file
A high frame rate for a video capture smoothes the image flow onscreen
The traditional frame rate for motion pictures is 24 frames per second (fps), and most television broadcasting uses technologies that emulate the same sort of capture rate At 24 fps and higher, the human eye doesn’t notice the flicker of the spaces between the frames; at lower rates, movement appears choppy or streaky
Figure 3-2:
The Options tab of the CAS Properties window allows you
to adjust zoom, flip the image horizontally
or vertically, and com-pensate for flicker caused by differing AC electrical cycle rates
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A slow frame rate of 1 fps makes no attempt to offer the illusion of smooth movement, but could be useful in monitoring a scene over a long period of time: spying on your cat over an eight-hour day or even more sneaky endeavors (Don’t break any laws, please; personal privacy laws are increas-ingly strict.)
Upgrading Your Laptop to Add a Webcam
While many current laptops come equipped with a tiny webcam and micro-phone, you can easily add external hardware to a modern machine External webcams and microphones often deliver higher-quality images and add flexi-bility: You can place the camera far from the laptop or hold it in your hand
to use it like a movie camera
Among uses of external webcams: capturing high-quality images of people for use in creating ID cards or an online database of faces This sort of arrangement is now commonly used for checkpoints at entrances to build-ings or events, and many hotels and cruise lines capture an image of the faces of their guests to help with security
Standard external webcams plug into a USB port on a laptop You can also purchase devices that communicate wirelessly using a WiFi network
Consider, for example, Microsoft’s LifeCam Web Camera The golf ball–sized unit captures video at as much as 1.3MP resolution (1280 ×1024) at 30 fps; you can set still-image resolution as high as 5MP (2560 ×2048), equal to most consumer-grade digital cameras The camera automatically adjusts for low-light conditions and also offers pan and tilt options
The Linksys Wireless-G Pan/Tilt/Zoom Video Camera sends live video to a WiFi system and from there to a local network or out onto the Internet See Figure 3-3 It includes advanced MPEG-4 video compression to produce a high-quality video stream at a high frame rate and resolution of as much as
640 ×480 Video features include an infrared (IR) filter cut, which allows you
to capture images in low light when using an IR lamp You can take and save snapshots (in JPEG format) of the image A security mode can instruct the camera to send an e-mail message with an attached short video whenever motion is detected in the field of view
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Figure 3-3:
You can control the Linksys WCV200 wireless camera from afar over the Internet