X-CD-Roast: CD Writer Software

X-CD-Roast is a fully X-based CD writer program. It is a front end for the command-line utilities cdwrite and mkisofs. X-CD-Roast therefore reduces the task of creating your own CDs to a few simple mouse clicks instead of a long study of any command-line parameters.

The newest version of X-CD-Roast (0.96a in August 1997) provides the following features:

At this time, it is not possible to create or copy multi-session CDs with X-CD-Roast. You also cannot master a CD without creating a CD image on a hard disk; you must provide the disk space for the data and for the mastered CD-image. Therefore, you need approximately 700MB times two of free disk space when creating a 650MB CD. Version 0.96a supports only a very limited set of CD writers. The next major update to 0.97 will include the cdrecord program which will handle most writers on the market. Non-SCSI writers will not be supported in the near future.

Prior to the installation of X-CD-Roast you should check whether you satisfy all system requirements.

Required Hardware

First, the basic steps when burning a Data-CD: The copying is very simple: first, an image of the original-CD is created on a free hard disk partition (called “image” or “image partition” from now on). This image contains every byte of the original CD and can therefore be up to 650MB in size. Now, you can do a verification run to compare the contents of the image with the original CD. This enables you to track down any read errors that might have damaged the image. The next step is to copy that image back to a CD-Recordable, a process called “burning”. At this point you can choose whether to simulate the burn process (the writer goes through all the motions and processes, but the write laser is off) or to do the real thing. I recommend that you do your first tests using the simulation mode—it could save you a few CD-Recordables.

Audio and mixed-mode CDs (CDs with one data track and additional audio tracks) can be copied as well, but this takes more effort. Each track of the original CD is read into a single file and saved onto the image partition. These tracks can now be written in any sequence you like, and you can also read tracks from more than one CD and so create your own “best-of” audio CD.

If you want to create a CD with your own files, you must first “master” the data. Collect all the files you wish to have on CD in a single directory tree mounted on your system. X-CD-Roast then converts this directory tree into a ISO-9660 CD image. Remember, this image will occupy about the same amount of space on your hard drive as your data to burn does. So, to master 600MB of data, you must have about 1.2GB of space. Finally, you burn this image on to a CD-Recordable.

In this section I briefly explain how a CD-Recordable and a CD writer work. This information is not necessary to use X-CD-Roast, but it can help you to understand the process.

The most common types of CD-Recordables are those with 63 and 74 minutes audio runtimes or 553MB and 650MB data capacities. The structure of a pressed “silver” CD is quite similar to a CD-Recordable. A pressed CD is built from a polycarbonate layer in which the information is pressed as pits. The sequence of “pit” or “not-pit” represents the data on the CD. After the press process, the layer is laminated with aluminum (giving it the silver look) for better reflection of the reading laser of a CD-ROM drive.

On the writable CD, the polycarbonate substrate, has a spiral groove that helps the laser stay on course during burning and playback. On that substrate a thin gold layer is laminated to provide the best possible reflection to a reading laser. Over the gold layer is a photosensitive dye layer, and over that is a clear protective lacquer. While you use a weak laser to read a CD, you need more power to write. The laser beam heats the photosensitive layer and creates a kind of hole that shows us the gold layer. When you read such a CD-Recordable, the holes in the photosensitive layer can be interpreted as “pits”, making it possible to read such a CD with all common CD-ROM and audio players. However, the “pits” are not as sharp as on a pressed CD and can cause troubles on a few older CD-ROM drives, which report occasional read errors, while others perform flawlessly.

Some recommended precautionary measures when dealing with CD-Recordables:

Figure 1. Schematic Drawing of a CD-Recordable