How do you rip DVDs and transfer the movies to Apple TV?

DVDs generally are copy-protected, and as a result ripping DVDs and formatting the films for the Apple TV may be illegal depending on the laws in your country. Please be sure to verify that your particular use is legal where you reside.

AppleTV Hacker has posted in-depth instructions on how to rip DVDs for the Apple TV using open source software.

What audio and video formats does the Apple TV support? Does it support video streaming and purchase directly from the Internet?

Apple reports that the Apple TV supports "AAC (16 to 320 Kbps); protected AAC (from iTunes Store); MP3 (16 to 320 Kbps); MP3 VBR; Apple Lossless; AIFF; WAV" audio formats and the following video formats:

• H.264 and protected H.264 (from iTunes Store): Up to 5 Mbps, Progressive Main Profile (CAVLC) with AAC-LC audio up to 160 Kbps (maximum resolution: 1280 by 720 pixels at 24 fps, 960 by 540 pixels at 30 fps)
• MPEG-4: Up to 3 Mbps, Simple Profile with AAC-LC audio up to 160 Kbps (maximum resolution: 720 by 432 pixels at 30 fps)

The Apple Support Site also has more information about the officially compatible file formats. Although it is not supported by Apple, and using it may void your warranty, the hardworking hackers at AwkwardTV have released a plug-in with support for additional file formats.

In an in-depth review that should be read in its entirety, the always excellent iLounge provides details about what these formats mean in "real world" use as well as some of the problems that the Apple TV has using some video files even when encoded in the above formats but using non-Apple software to do so.

Originally, the Apple TV had limited support for streaming video directly from the Internet -- it could download and play short previews and trailers from the iTunes Store, but nothing else. Beginning January 15, 2008, however, Apple released new software available as a free update that also made it possible to rent movies directly from a widescreen television via the Apple TV.

What is the difference between "syncing" and "streaming"? How many computers does the Apple TV support for each?

Apple TV only can be "synced" with a single computer, just like the iPod. This means that movies, TV shows, music, podcasts, and photos organized with iTunes on the "synced" computer are copied to the Apple TV as well, provided that there is adequate storage space on the Apple TV hard drive.

However, Apple TV also allows five additional computers, to "stream" content to the Apple TV over a wireless network. This content is not copied to the Apple TV. You can stream movies, TV shows, music, and podcasts, but annoyingly, you cannot stream photos. Photos only can be viewed from the synced computer.

The Apple Support Site has more details covering the differences between importing, syncing, and streaming content to the Apple TV, as well as information on how to sync photos to the Apple TV.

Does the Apple TV support 5.1 channel surround sound?

The Apple TV outputs a Dolby Prologic stereo signal. It does not support "true" 5.1 channel surround sound.

Interestingly, in an excellent MacWorld "First Look" regarding hacking the Apple TV, the author notes that:

The audio chip in the Apple TV is a Realtek ALC885, which the manufacturer describes as a "7.1+2 Channel High-Performance High Definition Audio Codec." The specs on this chip are quite impressive, and seem to indicate that the Apple TV’s reported audio-output limitation -- Dolby Pro Logic II -- is due to software, not hardware. In fact, Roughly Drafted reports that if you play a sample DTS audio file through your Apple TV, the Apple TV's optical digital-audio output jack does indeed put out 5.1 audio. On the other hand, the ALC885 also supports "advanced lossless content protection technology," so perhaps we have hardware DRM in our video-playing future.

For a technical overview of the audio standards that the Apple TV supports, might support, and does not support, you might also be interested in reading a blog entry from This Much I Know, first spotted by AppleTV Hacker.