21.9. Video Chats

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21.9. Video Chats

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21.9. Video Chats If you and your partner both have broadband Internet connections, even more impressive feats await. You can conduct a free video chat with up to four people

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  1. 21.9. Video Chats If you and your partner both have broadband Internet connections, even more impressive feats await. You can conduct a free video chat with up to four people, who show up on three vertical panels, gorgeously reflected on a shiny black table surface. This isn't the jerky, out-of-audio-sync, Triscuit-sized video of Windows videoconferencing. If you've got the Mac muscle and bandwidth, your partners are as crisp, clear, bright and smooth as television—and as big as your screen, if you like. People can come and go; as they enter and leave the "videosphere," iChat slides their glistening screens aside, enlarging or shrinking them as necessary to fit on your screen. Apple offers this luxurious experience, however, only if you have luxurious gear: • A video camera. It can be the tiny iSight camera that's embedded above the screens of iMacs and laptops; an external FireWire iSight camera; an ordinary digital camcorder (as long as your Mac has at least a G5 chip inside); or a golf-ball Webcam that connects via FireWire instead of USB. Tip: You and your buddy don't both need the same gear. If only you have a camera, for example, you can choose Buddies Invite to One-Way Video Chat (or Audio Chat). Your less-equipped buddy can see you, but has to speak (audio only) or type in response. • A fast processor. This is miserably picky information, but confronting it now will save you many headaches down the road: If your Mac has a 867-megahertz G4 processor or anything faster, you can have one-on-one video chats. To pull off a multiperson video chat, the Mac that initiates the call—invites everyone else to join—must contain a G5 processor or dual G4s running at 1 gigahertz or faster. If you want to join a multiperson video chat, you need an Intel G5 chip, a 1-gigahertz G4 chip, or dual 800-megahertz G4s. • Bandwidth. You need Internet upload/download speeds of at least 100 kilobits per second for basic, tiny video chats with one other person, and a minimum of 384 Kbps for four-way video chats. And those are for the smallest video windows.
  2. Starting a video chat at the highest video quality requires 1,800 Kbps—speeds that residential DSL packages may not be able to muster. Tip: As you're beginning to appreciate, iChat's system requirements are all over the map. Some features require very little horsepower; others require tons.To find out exactly which features your Mac can handle, choose Video Connection Doctor; from the Show pop-up menu, choose Capabilities. There's a little chart of all iChat features, showing checkmarks for the ones your Mac can manage. If you see a camcorder icon next to a buddy's name, you can have a full-screen, high- quality video chat with that person, because they, like you, have a suitable camera and a high-speed Internet connection. If you see a stacked camcorder icon, then that person has a G5 or a faster Mac that's capable of joining a four-way video chat. To begin a video chat, click the camera icon next to a buddy's name, or highlight someone in the Buddy List and then click the camcorder icon at the bottom of the list. Or, if you're already in a text chat, choose Buddies Invite to Video Chat. Figure 21-8. That's you in the smaller window. To move your own mini-window, click a different corner, or drag yourself to a different corner. If you need to blow your nose or do something else unseemly, Option-click the microphone button to freeze the video and mute the audio. Click again to resume. A window opens, showing you. This Preview mode is intended to show what your buddy will see. (You'll probably discover that you need some kind of light in front of you to avoid being too shadowy.) As your buddies join you, they appear in their own windows (Figure 21-8). And now, some video-chat notes: • If your conversation partners seem unwilling to make eye contact, it's not because they're shifty. They're just looking at you, on the screen, rather than at the camera—and chances are you aren't looking into your camera, either. • Don't miss the Video Full Screen command! Wild.
  3. • You can have video chats with Windows computers, too, as long as they're using a recent version of AOL Instant Messenger. Be prepared for disappointment, though; the video is generally jerky, small, and slightly out of sync. That's partly due to the cheap USB Webcams most PCs have, and partly due to the poor video codec (compression scheme) that's built into AOL Instant Messenger. • If you use iChat with a camcorder, you can set the camera to VTR (playback) mode and play a tape right over the Internet to whoever is on the other end! (The video appears flipped horizontally on your screen, but looks right to the other person.) • You can capture a still "photo"ofa video chat by -dragging the image to your desktop, or by choosing Video Take Snapshot (Option- -S). • Don't want to see yourself in the picture-in-picture window during your video chat? Choose Video Hide Local Video. (That's new in 10.5.) • This cutting-edge technology can occasionally present cutting-edge glitches. The video quality deteriorates, the transmission aborts suddenly, the audio has an annoying echo, and so on. When problems strike, iChat Help offers a number of tips; the Video Connection Doctor can identify your network speed. (iChat video likes lots of network speed.) • Just as you can save your typed transcripts of instant message conversations, you can record your audio and video chats. Once you start a chat, choose Video Record Chat. Your buddy is asked if it's OK for you to proceed with the recording (to ward off any question of those pesky wiretapping laws); if permission is granted, iChat begins recording the call. When you've got what you want, click Stop. Your recordings are automatically saved into Home Documents iChats(AAC files for audio conversations, MPEG-4 files for video chats). From there, you can drag them into iTunes to play or sync them up with an iPod or iPhoto. Yes, you can now relive those glorious iChat moments when you're standing in line at the grocery store. 21.9.1. Bluescreen Backdrops and Video FX If your video chats look like a bunch of cubicle-dwellers sitting around chatting at their desks, you can liven things up with one of Leopard's most glamorous and jaw-dropping features: photo or video backgrounds for your talking head. Yes, now you can make your video chat partners think you're in Paris, on the moon, or even impersonating a four-panel Andy Warhol silkscreen.
  4. Note: The iChat and Photo Booth backdrop effects are serious, serious processor hogs; they require, at minimum, a Mac with a Core 2 Duo processor. And bandwidth, man, serious bandwidth—at least 128 Kbps for both upload and download speeds. Here's how to prepare your backdrop for a video chat: 1. Go to iChat Preferences Audio/Video. A video window opens so you can see yourself. 2. Press Shift- -E (or go to Video Show Video Effects). The Effects box appears, looking a lot like the one in Photo Booth (Chapter 10); a lot of the visual backdrops are quite similar. Click the various squares of the tic- tac-toe grid to see how each effect will transform you in real time: making your face bulbous, for example, or rendering you in delicate colored pencil shadings. The first two pages of effects all do video magic on you and everything else in the picture. If you want one of those, click it; you're done. There's no step 3. Your video-chat buddies now see you in your distorted or artistic new getup. The second two pages of effects, however, don't do anything to your image. Instead, they replace the background. This is the really amazing part. In TV and movies, replacing the background is an extremely common special effect. All you have to do is set up a perfectly smooth, evenly lit, shadowless blue or bright green backdrop behind the subject. Later, the computer replaces that solid color with a new picture or video of the director's choice. iChat, however, creates exactly the same special effect (Figure 21-9) without requiring the bluescreen or the greenscreen. Read on. 3. Click the background effect you want. Suppose, for example, that you've clicked the video loop showing the Eiffel Tower with people walking around. At this point, a message appears on the screen that says, "Please step out of the frame." 4. Duck out of camera range (or move off to one side).
  5. See, iChat intends to memorize a picture of the real background—without you in it. When you return to the scene, your high-horsepower Mac then compares each pixel of its memorized image with what it's seeing now. Any differences, it concludes, must be you. And that is how it can create a bluescreen effect without a bluescreen. Note: To make this work, both the camera and the background must be perfectly still. If the lighting or the visuals shift or change in any way, you may get some weird, glitchy effects where your real background bleeds through. 5. When the screen says, "Background detected," step back into the frame. Zut alors! You are now in virtual Paris. Go ahead and start the video chat with your friends, and don't forget your beret. If you want to clear out the background or change it, click the Original square in the middle of the Effects palette and then choose a different backdrop. (You can also change backdrops in mid-chat by choosing Video Show Video Effects to open the effects palette.) If things get too weird and choppy onscreen, you can restore the normal background by choosing Video Reset Background. (That's also handy if you suddenly have to have a video talk with your boss about your excessive use of iChat while he's away on his business trip.) Figure 21-9. Top left: You have plenty of backgrounds to choose from for your next video chat. Click an effect to add it to your chat window. Click the small arrows at the bottom of the window to advance or retreat through the various effects styles. Click the Original square in the middle of the window to erase the effect and start again from scratch. Lower right: Let the live bluescreen action begin!
  6. Tip: You can use one of your own photos or video clips as iChat backdrops, too. In the Video Effects box, click the arrows on the bottom until you get to the screen with several blank User Backdrop screens. Next, drag a photo or video from the desktop directly onto one of the blank screens. Click it just like you would any of Apple's stock shots.
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