Section 5.11. Webcams


5.11. Webcams

Attracting voyeurs worldwide, Webcams provide a Web site's visitors with a regularly updated glimpse into another place. Thousands of free Webcams, viewable from Web sites worldwide compete for your attention, dishing up live-action ant farm excitement, sleeping cats, and even volcanic eruptionsif you happen to be watching at the right moment.

Most Webcams just take snaps of the action every 30 seconds or so, automatically updating the Web site with the latest photo at regular intervals. The fanciest Web sites display a live video stream, just as if you were behind a camcorder's lens. Posting a video stream is much more complicated than posting a single picture, so "live video" Webcams are still the exception, rather than the rule.

Setting up your own Webcam takes considerable time and tweaking to make everything run correctly. Once you set the thing up, however, your work's over. Your PC automatically grabs an updated picture from your video camera and posts it on your Web site to share with the world.

The following sections take you through everything you need to add a Webcam to your PC, and then show you how to share your pictures with the world.

5.11.1. Video Camera

Most Webcams are really just video cameras . They create video streams live movies of whatever they may be aiming at, be it a waterfall, a massive swell, or a sleeping cat. When you attach these to your own PC, you can watch the entire video stream. Your PC extracts a single image from that video stream every 30 seconds, and then sends that particular picture to your Web site for the rest of the world to see.

When installed, most Webcams place their icon in Windows XP's My Computer program; open My Computer to see the camera's icon. Double-click the camera's icon to view the stream and adjust your camera's position slightly should the cat move.

Webcams fall into the following general categories; a few models are shown in Figure 5-13.

  • Desktop Webcam . At the lowest end of the scale, small, often ball-shaped video cameras (as shown in Figure 5-13, top) cost less than $50 at most computer or office supply stores. Once plugged into a USB port and taped to your monitor, the Webcam lets your friends watch you during instant messaging chats (see the online appendix, "Other Cool Things You Can Do Online," available on the "Missing CD" page at www.missingmanuals.com). The small camera's ease of use comes with some drawbacks, as they don't allow much (or any) control over focus, brightness, or clarity. But, hey, at least some include their own doublesided sticky tape.

  • Digital camcorder . If you already own a digital camcorder, connect it to your PC's FireWire port (Section 1.8.3.1) to create a makeshift Webcam that's a huge leap in quality from the desktop Webcam models.

  • Network Webcam . Most Webcams remain tethered to your PC with a short USB or video cable. Network Webcams come with a network port so you can plug them right into your network. Since network cables can extend for hundreds of feet, network Webcams can sit far from your PC, which can be handy for rooftop or front-door surveillance. These models are more expensive than desktop Webcams and include extra circuitry to convert the camera's video into your PC's network signals. Cheap models start around $200, with prices rising quickly for higher-quality cameras.

    Figure 5-13. Top: Logitech's QuickCam Express ($50) doesn't offer large, clear pictures or automatic focus. But it's fine for close quarters or instant chat programs where the video looks a little grainy, anyway.
    Middle: The Linksys WVC54g wireless Webcam ($200) comes in handy when mounting the camera far away from the PCon the rooftop, for instance, letting you view the front door or yard.
    Bottom: On the high-end, Axis Communications' $1,669.99 roof-mounted, fully trackable Webcam sends streaming video accessible over the Internet. You can view many network Webcams, both wired and wireless, from any Internet-connected PC. Therefore it's important to password-protect your network Webcam if you don't want strangers peeking in.
  • Wireless Webcams . Wireless Webcams remove the PC's tether altogether, and convert the video to network signals, which the camera then transmits wirelessly to your PC. Wireless Webcams grant free movement, letting you move the camera to the room's other bookshelf during the party, for instance, or you can attach it to the cat's collar for a CatCrawlCam.

  • Viewer-controllable Webcams . The high-end of the scale. These cameras offer "point and zoom" controls to let site visitors watch all angles of the action, be it cars in the Plantation Pancake House parking lot or surfers zipping between the Ocean Beach Pier's pillars. Logitech's computer-controlled desktop model, QuickCam Orbit, sells for around $100. Axis Communications (www.axis.com) sells high-quality outdoor models costing more than $1,500.

5.11.2. Video Capture Software

Once you plug in your Webcam, Windows XP lets you view the camera's images immediatelyjust double-click its icon inside My Computer. To share those images with others, you need extra software. Many Webcams come with their own software. Alternatively, instant messaging software automatically recognizes any Webcam installed on your PC and handles the chores of transmitting video to your friends during chats.

But uploading photos to a Web site requires more work on your part, as well as Webcam software to periodically grab the camera's images and upload them to the Internet. Luckily, Webcam software's quite inexpensive, and some Webcams even toss free software into their boxes. If yours doesn't have any, Microsoft offers the free but minimalist Timershot software (http://www.microsoft.com/windowsxp/downloads/powertoys/xppowertoys.mspx). For a simple Webcam that uploads photos automatically to the Internet, Timershot may be all you need.

The more advanced TinCam Webcam software (www.tincam.com) offers easier controls and more features, letting you grab images from two or more cameras simultaneously , send video streams, and send files to several Internet destinations. TinCam offers a free trial for 30 days, letting you toy with the settings before committing to the full $19 price.

5.11.3. Internet Connection, Web Site, and a Web Page

Your Webcam and its software chug along as a team, letting you peek at your PC for a view of an exotic remote location, should your camera be pointing that way. But to place that view onto the Internet, you need Web space (see the online appendix, "Other Cool Things You Can Do Online," available on the "Missing CD" page at www.missingmanuals.com)a little storage area on the Internet for housing files, including a Web site. You may already have some but don't know it: many ISPs offer their customers free Web space. Most limit that space to between 5 and 15 MB, which is more than enough for a photo.

Setting up your Webcam software so that you can funnel images to a Web site works much like setting up a Web browser (Section 13.1) or email program (Section 12.2). The Webcam software demands these five all-important pieces of knowledge:


Note: The following information serves as your "house key" for entering your Web space. Write it down and store it in a very safe place.
  • Host address . Your Web site provider gives you this. It specifies your Web space's parking place on the Internet. The address looks like ftp.myisp.com, members .isp.net , or something similar.

  • User name . Your Web site provider gives you your user name, too. You probably already use this same name to log onto the Internet, or perhaps to check your email.

  • Password . Your Web site provider also gives you your password. Just like the user name, this is often the same password you use to log onto the Internet or check your email.

  • Folder name . Web space lets you create folders, just like on your PC. You probably create this folder yourself when you create your Web site.

  • File name . Most Webcam software automatically supplies you with the name of the file that contains your snapped image.

POWER USERS' CLINIC
Digitizing Old Movies

Think twice before volunteering to digitize those old reels of film sitting in Aunt Hannah's closet. That quick-and-easy job you imagine may not be so simple in reality.

The pros digitize old films with a telecine , a pricey, specialized movie scanner that digitizes each frame at a high quality, and then quickly stitches the frames back into a digital movie. Unfortunately, these pros charge upwards of $200 per hour . Cheaper film-to-DVD transfer services, dubbed "Transfer Mills" by the pros, simply point a digital camcorder at a wall and capture the movie as it plays back.

You, too, can scan each frame and join them into a movie with Windows Movie Maker. But since old films contain 24 frames each second, you may not live long enough to finish the job.

To speed things up, you can point your own digital camcorder at the wall and capture the projected movie. That gives you time to play with the settings until everything looks right, a luxury missing when you depend on the Transfer Mills. But before whipping out your wall cleaner, consider these obstacles:

  • Find a projector . Old films traditionally outlast their projectors. If Aunt Hannah's projector died years ago, you can probably find an old one on eBay (www.ebay.com). But without a thorough cleaning, aging rojectors can jam, incinerating your treasured film. Call a local camera repair shop for recommendations on projector cleaning and tune-ups.

  • Frame rate . Old movie cameras and today's camcorders don't capture video with the same number of frames per second, leading to flicker. To compensate, flip through your digital camcorder's menus for its Shutter Speed setting. Then, while watching the projected movie through the digital camcorder's LCD screen, try different shutter speed settings until the flicker disappears.

  • Focus . To keep the projected scenery from fooling your camcorder's autofocus , switch the camcorder to Manual Focus. Then focus it on the projected image.

  • White balance . Change this setting from Automatic to Manual, or try the Daylight setting. You may want to experiment for best results.

Point the projector directly at the wall, or at a piece of white matte paper on the wall. Set up the camcorder on a tripod directly above the projector, adjust its settings, and then film the projected movie. Practice a few times, tweaking the camcorder's settings until everything looks good. When you capture everything, run your movie through Windows Movie Maker, and then burn it to DVD.

The resulting movie certainly won't look as good as those restored by specialists. But the price is right, and at least you can finally view your old movies' content, rather than their containers.


Enter all five items into your Webcam software so it knows where to send the image, and then tell it how often to send each new image. Once the image appears on your siteconstantly updated courtesy of your Webcam softwareyou need one more thing: a page that displays the image. Most Webcam software, including TinCam, include sample Web pages. Place that Web page in your Web space and list that Web page on your Web site's menu so visitors can choose to see it in their Web browsers.

5.11.4. Troubleshooting Webcam Problems

Windows XP makes setting up Webcams fairly easy. When Windows XP recognizes the camera, it automatically passes that information along to your Webcam software. But when Windows XP doesn't recognize your camera, you're in trouble.

Fortunately, that rarely happens. Windows XP manages to stay on good terms with most USB devices (Section 1.8.1), recognizing them as soon as you plug them in. If it doesn't recognize your Webcam, you probably need to install its latest driver the piece of software that lets Windows XP and your Webcam communicate on cheery terms. Download the driver from the Webcam manufacturer's Web site and run the driver's installation program.




PCs
PCs: The Missing Manual
ISBN: 0596100930
EAN: 2147483647
Year: 2005
Pages: 206
Authors: Andy Rathbone

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