IChat

Infobox Software
name = iChat AV



caption = The official iChat icon
developer = Apple Inc.
frequently_updated = yes
operating system = Mac OS X
genre = Instant messaging client
license = Proprietary
website = [http://www.apple.com/macosx/features/ichat/ Apple: iChat]

iChat AV is an AOL Instant Messenger (AIM), .Mac, ICQ and XMPP client by Apple Inc. for their Mac OS X operating system. Using a Jabber-like protocol and Bonjour for user discovery, it also allows for LAN communication. iChat's AIM support is fully endorsed by AOL, and uses their official implementation of the AIM OSCAR protocol. Using a Jabber transport, iChat users may also integrate their MSN, Yahoo! and Google Talk contacts into the Jabber pane.

As of Mac OS 10.5, iChat bears the latest version of Apple's Aqua interface and uses speech bubbles and pictures that are meant to personify the online chatting experience. With iChat, green (available), yellow (idle), and red (away) dots can be seen next to the name of each connected user on the buddy list. To cater for color-blind users, this can be altered to show different shapes to illustrate status rather than color.

History

In June 2003, Apple Inc. announced "iChat AV Public Beta", a new version of iChat that added voice and video chat capabilities. It also introduced the iSight camera, designed specifically for use with iChat AV. These capabilities are based on the industry-standard Session Initiation Protocol (SIP) for video chat and audio chat. The final version of the software was shipped with Mac OS X v10.3 and became available separately on the same day for users of Mac OS X v10.2 for 29.95USD. Apple eventually discontinued sale of iChat AV separately; it can now only be acquired through OS X or with a new Mac.

In February 2004, America Online introduced AOL Instant Messenger (AIM) version 5.5 for Windows-PC users. This version allowed video (but not voice) chats over the AIM protocol and was compatible with Apple's iChat AV. On the same day, Apple released iChat AV 2.1 Public Beta to allow Mac OS X users to video conference with AIM 5.5 users.

In June 2004, Steve Jobs revealed that the next version of iChat AV (commonly called iChat 3) would be included with Mac OS X v10.4 (Tiger). iChat 3 supports up to four people in a video conference and ten people in an audio conference. Additionally, video conferencing uses H.264/AVC, which offers better quality than the H.263 codec used in previous versions. This release also supports the Jabber protocol (which can be directly used to connect to Google Talk and indirectly be used to connect to users of services including Yahoo! Messenger and MSN Messenger as well). However, support is limited as it does not support several common Jabber/XMPP features like account creation, service discovery and full Multi-User Chat support.

In October 2005, iChat received support for encrypted communications, but only for paid subscribers to Apple's .Mac service. These features are part of iChat 3.1, released as part of the Mac OS X 10.4.3 update on October 31 2005. This version also added support for Jabber multi-user chat.

In March 2007, Apple released the Mac OS X 10.4.9 update which allowed USB video device class (UVC) cameras to be used with iChat, rather than just FireWire-compliant cameras. This allows a much wider range of cameras to be used with iChat AV.

With the release of Mac OS X Leopard, iChat received new features including: iChat Theater, Backdrops, and Screen Sharing. iChat Theater allows users to share any file that is supported by Quick Look, including photos, Keynote presentations, and movies over a video chat session. "Backdrops" allow users to insert movies or photos as a backdrop in video chats. Screen Sharing allows two users of Mac OS X Leopard to have control of the same desktop and work collaboratively. Minor features in the new release include multiple logins, animated icons, use of Photo Booth effects in live video chat, and tabbed chats.

Third party add-ons

Several third-party add-ons exist that extend the functionality of iChat.

ChatFX

[http://www.scriptsoftware.com/chatfx ChatFX] adds special video effects created by the Quartz Composer application included in Apple's free Developer Tools. ChatFX changes the video in a video conference through use of Quartz Composer compositions. Special video effects like bluescreen, distort, display of desktop, sobel, comicbook, ghost, etc. come with ChatFX but an unlimited number of effects are possible by creating new compositions in Quartz Composer. Apple Inc has implemented the functionalities of ChatFX in the version of iChat included with Mac OS X 10.5 Leopard.

Chax

[http://www.ksuther.com/chax/ Chax] adds tabbed windows and auto-accept of messages and file transfers. Chax also prevents iChat from pausing audio-video (AV) chat while simultaneously transferring files. The ability to animate buddy icons, which was absent in versions of iChat before Mac OS X Leopard, can also be added through Chax. It also can remove the html tags that are normally visible to the ICQ correspondents of iChat. It was developed by Kent Sutherland and is similar in functionality to AIM+ and DeadAIM, which added similar features to the Windows version of AOL's AIM client.

iUSBCam

Although a FireWire video camera, such as Apple's iSight, is among Apple's requirements for iChat AV video conferencing, [http://www.ecamm.com/mac/ichatusbcam iUSBCam] works around the iChat's limitations before Mac OS X 10.4.9 by enabling the use of USB cameras. It also provides basic picture adjustment and the ability to broadcast and automatically save the contents of the screen.

iGlasses

[http://www.ecamm.com/mac/iglasses/ iGlasses] gives the user control over the brightness, contrast, and color of the streamed video image. It is especially useful for sub-optimal lighting situations where the iChat user appears too dark, for example. It also provides mirroring and image rotation — useful when an iSight camera is mounted upside down. The "night vision" mode reveals the iSight's high sensitivity, allowing viewing of a darkened room, and making rudimentary security monitoring easier.

howMacster

[http://www.showmacster.com ShowMacster] lets the user stream photos, video, and sound files in their video chat as well as a live view of their screen. ShowMacster also allows "writing" of simple markup onto streamed images -- adding circles, lines, and the like in a set of primary colors and widths. Using a live view of a section of the screen together with this markup capability, a user can do limited whiteboarding, albeit in one direction only. If two (or more) iChat users each use ShowMacster they can communicate their ideas back and forth, but this is not true whiteboarding; the markup is streamed in video only, so there is no shared document which the users both (all) modify, nor is there a way to save the markup.

ee also

*List of Jabber client software
*Comparison of instant messaging clients
*Comparison of instant messaging protocols
*List of USB video class devices - A list of USB cameras that will work with Mac OS X 10.4.9 or later
*Jens Alfke - the initial developer of iChat
*Video conferencing
*macam - Open source USB webcam driver for Mac.

External links

* [http://www.apple.com/macosx/features/ichat.html Apple's product page on iChat]
* [http://www.aol.com AOL]
* [http://www.jabber.org Jabber Software Foundation]
* [http://allforces.com/2005/05/06/ichat-to-msn-through-jabber/ iChat to MSN through Jabber]
* [http://www.ecamm.com/mac/ichatusbcam/ iChatUSBCam]
* [http://www.ksuther.com/chax/index.php Chax homepage]
* [http://www.scriptsoftware.com/chatfx ChatFX homepage]
* [http://docs.info.apple.com/article.html?artnum=93208 Using iChat AV with a firewall or NAT router]
* [http://osxportableapps.sourceforge.net/p_ichat/index.html Portable iChat] - Allows you to open iChat as portable application from external drive]
* [http://www.macosxhints.com/article.php?story=2004091700084674 Log into ICQ using iChat]