Disc Images

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Think of an image as a complete picture of the disc you want to create, a blueprint that includes every file (and the proper version of each of those files). In essence, an image is the contents and structure of your disc, before it is a disc. An image is the backbone of what GEAR is designed to record, representing a file or collection of files. With GEARs powerful recording engine, images can be created in two ways: Virtual Image or Physical Image.


Virtual Image

Whenever you create a project in GEAR, a virtual image is created. This is an administration file containing necessary information about the files you plan to store on disc. Included in this file will be the directory structure to be used on the disc and the location of the data files on your hard disk(s). When you start copying your data to disc, the virtual image will moderate the actual recording process by loading the appropriate files from your hard drive(s) in their correct order and writing each file to its assigned place on the disc.

A virtual image is really like a file or an electronic table of contents that contains an alias for every file you're planning on recording to disc. It doesn't contain your actual files, but it knows where they all are and the order in which to record them.


Physical Image

A physical image on the other hand, contains actual bit-to-bit copy of the track that will be recorded on the disc, and therefore contains copies of all the files you loaded into the virtual image. The physical image is usually one complete file. Consequently, a physical image can be very large. Despite it's size, a physical image is sometimes very useful. If you encounter errors due to low data transfer rates when attempting to record your data to disc, you should consider creating a physical image. A physical image is also appropriate to use when the transfer rate for recording has to be increased from it's normal level on your system (for example, when recording a large number of small files).

A physical image will take significantly more hard drive space than it's virtual counterpart. However, since all the required files for recording your disc are already present in a physical image, it will transfer data between your computer and CD-R/DVD-R drive much faster.


External or Foreign Image

With GEAR's extensive capabilities you can also write external or foreign images to CD/DVD. An external or foreign image is a physical image file produced by some software tool other than GEAR (for example, a video game authoring engine).

Occasionally, software vendors distribute software in the form of a downloadable physical image file (usually, an ISO-9660 image). GEAR allows you to open and read these image files, so that you can create a physical copy in the form of a CD or DVD. If you have a bootable ISO image, GEAR will be able to open it and burn it to disc to make a bootable disc.

Furthermore, with some CD formats GEAR must use foreign images because GEAR is not designed to create images for the following CD formats: Native UFS, Apple HFS, CD-I, Video CD, Photo CD, DVD-Video and DVD Audio. These disc types can currently only be processed by means of an external/foreign image.

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