Apple VisualHub manual What is it and what does it do?, How does it work?, How do I set it up?

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What is it and what does it do?

Xgrid is Apple’s clustering technology built into Mac OS X.

Xgrid can speed up a batch conversion by dealing out a video to each available CPU on your network for conversion.

When you have more than one video in the file list and then check the "Enable Xgrid Encoding" checkbox, VisualHub will enlist the help of any Macs on your local network that have Xgrid enabled to distribute the load of batch encoding. If you have a multi-processor Mac, Xgrid may also speed up the encoding process, with each processor working on a different video.

For example, a PowerMac G5 Quad under normal circumstances will only convert one video at a time, leaving anywhere from 2.5 to 3 of its processors idle. With Xgrid, the same computer can utilize all 4 processors to their highest capacity.

How does it work?

There are two different types of Xgrid-enabled computers: Controllers and Agents.

The Controller is the computer responsible for telling the Agents what to do and to collect completed files. The computer running VisualHub is the Controller. Controllers must be running 10.4 (Tiger) or higher and connected to a network.

Agents take orders from the Controller and do the grunt work of video compression. Agents must be running 10.3.9 (Panther) or later and connected to the same network as the Controller. An Xgrid process running on an Agent will not adversely affect the use of that computer; Xgrid processes always run at very low priority.

A Controller can also be an Agent to itself. You’ll see later how that can be a very good thing.

When you start an Xgrid-enabled batch, the Controller will do all the necessary detection and decision of settings for each video, one by one. That information is sent to the Xgrid to await assignment. When an Agent is available, the Xgrid will submit that information along with the video to be converted over the network to an Agent. Once all videos are sent to the Xgrid, VisualHub will wait to hear back from Agents with completed videos. The progress bar will update for every completed video. Once all videos are received, VisualHub will execute any post-conversion routines it normally does.

How do I set it up?

When Xgrid is enabled for the first time (by clicking on the “Enable Xgrid Encoding” checkbox in the main window, you will be prompted to start the Xgrid Controller. This is a one-time action requiring an administrator’s password. A tweak is also made to the number of processes that can run at any given time, as Xgrid may spawn more than 100 background processes.

You will also have to set up each Xgrid Agent.

Tiger Agents: Go to the Sharing Preference Pane in System Preferences. You will see a checkbox labeled Xgrid. If you

select the checkbox, the system will prompt you to edit the Xgrid settings. Click the “Configure” button to make these changes. Use the settings in the screenshot to set up your Agent. For added security, you can have the Agents only accept orders from a specific controller.

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Contents VisualHub Users Guide This page unintentionally left blank. Whoops Table of Contents Crash Course Adding Files, Saved File Location Easy SettingsIntroduction WorkflowITunes More Information What Is It?Easy Settings One-by-One What Plays It?PSP Standard/Anamorphic AVC Encoding Advanced SettingsApple Spokesperson on FireWire at MUG meeting Ready for Final Cut Force AnamorphicAfter Conversion DVD DVD VHS CD Vinyl Author as DVDDVD Tidbits Burn When DoneForce AVI Profile Pixels WideMP4 Hint for streaming WMV Xbox360 Playback CompatibilityMpeg MPEG-2 Encoding Hdtv 720p Mpeg ProfilesTiVo Transport StreamFlash Specialized Controls Raw .flv formatTick, on The Infinity Ball AdvancedOption Explanation Xgrid How does it work? What is it and what does it do?How do I set it up? Important notes on Xgrid Tidbits Pause/Resume Conversion Video StitchingConversion from DVD Post-Conversion ActionsTroubleshooting How can I speed up VisualHub? Hey, my video’s out of sync. What gives?Want to convert a DVD I bought What’s with all these lines in my converted video?Appendix Vermiform appendix Cheat Codes Explanation String Add your ownSupported Codecs/Formats Video Codecs Extra InformationCredits and Other Info Ffmpeg

VisualHub specifications

Apple VisualHub was a versatile multimedia application designed for Mac OS X, aimed at simplifying the process of converting video files into various formats. Launched by a small developer known as TechSpaghetti, VisualHub quickly gained popularity due to its user-friendly interface and powerful functionality.

One of the main features of VisualHub was its ability to convert videos to a wide range of formats, including MP4, AVI, MPEG, and more. This flexibility allowed users to prepare video content for different devices such as iPhones, iPods, and Apple TV. The drag-and-drop feature enhanced user convenience by enabling users to simply drag video files into the application for immediate conversion.

VisualHub was built on a combination of robust technologies, leveraging FFmpeg, a popular multimedia framework, to handle video processing. This underlying technology empowered the application to support a diverse array of input formats and deliver high-quality output quickly. Additionally, VisualHub utilized a streamlined codebase that optimized performance and improved conversion speed compared to many of its competitors.

Another noteworthy characteristic of VisualHub was its batch processing capability. Users could efficiently convert multiple videos at once, saving valuable time, particularly for those who needed to process large collections of video files. This feature, coupled with its intuitive interface, made it accessible for both casual users and more advanced video enthusiasts.

In addition to conversion, VisualHub also offered basic editing capabilities, including trimming video clips and adjusting audio settings. This provided users with some level of customization before finalizing their videos.

Despite its many strengths, VisualHub faced challenges, particularly as the digital landscape evolved with the rise of cloud-based services and streaming platforms. However, its legacy as a user-friendly and efficient video conversion tool remains recognized among macOS users who sought a straightforward solution for handling their video files.

In conclusion, Apple VisualHub was a significant tool in the realm of multimedia applications for Mac, known for its extensive format support, batch processing, and ease of use. While it is no longer actively maintained or available for purchase, its impact on video conversion software continues to be appreciated by those who utilized it during its prime.
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