This time around in Ask TUAW we'll be looking at questions about iTunes sharing, activating iChat effects on older machines, encoding video for the iPhone, Migration Assistant, disabling an internal iSight to use an external webcam, and more.

As always your suggestions are most welcome, and questions for next week should be left in the comments. When asking a question please include which machine you're running and which version of OS X, as certain answers will vary between different Macs and Tiger vs. Leopard, etc. And now, on to the questions!

Stinky12694 asks

My mom, my sister and I all have Identical MacBooks, and recently, I turned on the ability to share our iTunes libraries. And although we can access each other's music libraries and podcasts in front row, whenever we try to access each other's videos, it says "front row is not authorized to play this content". I checked the iTunes sharing preferences, and it is set to share the entire library on all laptops. So how can I watch their videos?

We need a bit more information. Do the videos in question have DRM? If so, obviously you'll need to make sure your machine is authorized to play them. Secondly, can you play the videos directly in iTunes itself? If so, the problem is probably similar to this mp3 bug. You can also try pulling the videos out of the iTunes library (put them in ~/Movies) and then see you if you can watch them over Front Row.

Aaron Ruhlig asks

I REALLY want to have shared access to any iTunes library on my home network (Mac or PC) from my Apple TV and/or another iTunes library regardless of whether iTunes is up and running on the sharing computer! Is there any way to accomplish this in either OS X or XP?

No, iTunes itself acts a server so you won't be able to access a library on a machine where it's not running. Frankly, would it be that hard to leave iTunes running on all your machines? If you really want to keep all your music always available on your network you might want to consider hosting all your music on a NAS with a built-in iTunes server like the Roku SoundBridge or the Buffalo LinkStation Live. Alternatively, you could run a sharing box via the Firefly Media Server open-source software.

A. Jay asks

With a PowerBook G4 12" 1.5 running 10.5.2, is there any possible way to 'allow' iChat effects like backdrop in video chat, or other things that appear to be require more CPU? Or, is Intel just needed for something like that? The addition to dimming the top bar is unavailable to me.

There is Ecamm's PowerBoost which will enable the Photo Booth-style effects, but even it won't allow the backdrops. There's also ChatFX which did backdrops before iChat 4, but it's not working in 10.4.10+ or Leopard. I'm afraid that it's just not going to be possible to get the backdrops on a PPC machine in Leopard.

When converting DVDs to be played on the iPhone(VIDEO_TS floders to an .mp4 file), what format is best to have a video that will look decent on an HDTV as well as on the iPhone(H.264/MP4 and what settings for each)? My intentions are playing the video on an HDTV over the Component Out. Similarly, I can record HD video from my DVR over firewire, if I create a file that is 1920x1080 or 1280x720 would it be able to play on the iPhone, on the phone or through video output? I seem to recall older iPod doing some sort of on the fly encoding to allow the file to play on or off the iPod?

If you look at the iPhone tech specs you'll see that the highest resolution video the iPhone supports is "H.264 video, up to 1.5 Mbps, 640 by 480 pixels, 30 frames per second." You'll want to encode at the highest rate the iPhone supports; I always recommend VisualHub ($23.32) for this.

Johan asks

The SuperDrive on my C2D 2.33 GHZ Macbook Pro has gone wonky - it accepts CDs but spits out any DVD, whether in Windows or Leopard. Since new Superdrives are expensive and I don't really use disks much anyway, I have been thinking about buying an external DVD burner instead. Lacie and MCE make some DVD burners explicitly for Macs - are these the only that will work? Some of them (particularly the MCE ones) look like an enclosure with a standard Pioneer DVD burner installed. Is it possible to save money by buying the enclosure and DVD burner separately instead?

No, those are not the only drives that will work. However, I would recommend going with a vendor with official Mac support because otherwise you will not have access to firmware updates, etc. In addition, you'd also be better off with a FireWire (or dual interface USB 2.0 / FireWire) drive. Personally, I really doubt you'll end up saving that much money trying to do it yourself with a separate enclosure and drive. I've never used it myself, but as an example this OWC Value Line Drive is only $85.

emil asks

I have a Macbook at home running 10.5, and an account with short username 'emil.' I have a Mac Mini at work running 10.4 containing an account with the same short username. I'd like to use the migration assistant to move my files and installed applications over to the Macbook. How can I move this account over without running into problems caused by their names being the same?

Your answer is on this Apple Support Document. It will copy over the files, replacing the ones on the MacBook. However, it will not delete the MacBook files but put them in the Deleted Users folder (in /users) where you can find them and copy them back. However, before you do anything make sure you have a complete backup of the MacBook in case something goes wrong.

Gui asks

I'm running leopard on a macbook. Is it possible to enable subtitles on FrontRow, is there any 3rd prty app that does that trick, or should I keep using VLC for that?

For the time being I would recommend continuing to use VLC. Apparently it used to be possible to get subtitles by installing Perian, but even that seems to be broken for a lot of people with the most recent QuickTime release. Nonetheless, you might try what is suggested here which appears to have worked for some people.

Steve asks

I have the latest version Macbook and I was wandering if there's a way you can use an external webcam with Photo Booth. BTW, I'm running OS X 10.5.2

Check out this thread on Apple Discussions. You can apparently disable your internal iSight with this AppleScript but that will also disable any other USB webcam. It seems that you can still use a FireWire camera, however. Nonetheless, there's a good tip at the bottom of the thread (which I am not in a position to confirm). Ken Aspeslagh says there: "if a program (like PhotoBooth for example) doesn't allow you to choose which camera to use, there's an easy way to force the program to not use the built-in iSight... simply start video from the built-in iSight going in another app (like iChat for example), then with that video still running, open the app you want to use with the external cam."