VCD is a well-defined and specific format, much like CD-DA for audio. Like audio, it requires a precise implementation of file structure so that it will play back correctly on a VCD or DVD machine which does not plug into a computer.
The VCD has one or more MPEG-compressed data streams recorded without the usual ECC of files. As with CD-DA, it is assumed that any errors will be unnoticed in the result. Unlike CD-DA, the data stream looks to be a true file and can be read (as a DAT) to your computer. However, since it does not have ECC, it can be too large to write back to a disc as a conventional file - and would not be recognizable in a VCD player if it were. Many MPEG players will play back DAT files as well as MPG's, even though they are slightly different internally.
To create a VCD, two steps are required. First, a whitebook MPG must be generated, then it must be recorded with software designed for that purpose. There may be boards or devices which create whitebook MPG's directly, but since those files are very difficult to edit, the preferred starting point is an editable AVI. The AVI from a capture device is most often edited with ULead's Media Studio or Adobe's Premiere; the latter is the choice of most serious users. The edited file can be saved with your choice of codec or those using Premiere and the Xing plugin can render directly as a fully compliant MPG. The ULead output is not fully compliant, but is acceptable to VCDC 3.5b and above. Both hardware and software encoders for MPEG are available. The Xing software implementation is relatively fast and consistently generates true whitebook code when the VCD option is selected.
The VCD format requires specific folders and files and the DAT itself must be recorded without ECC. Therefore, a dedicated program such as VCD Creator (a component of Easy CD Creator Deluxe) is required. VCDC will not record a non-compliant MPG file, so you will not waste a blank by discovering non-whitebook format after the fact. Note that relatively few VCD or DVD players will handle CD-R. Early Sony models accepted them without complaint, but later models (except the very high-end) do not. Similarly, first-generation DVD-ROM players do not read VCD's recorded on CD-R. Second- and later-generation DVD-ROM is MultiRead and should handle either CD-R or CD-RW. That is particularly advantageous in the VCD format because of the time and effort required in preparing and editing material. With audio, one can simply DAE the source to WAV files, then rearrange them and burn them to CD-DA. Theequivalent compilation capability in VCD requires a mastering program which will read DAT (as VCDC does). Otherwise, one may either generate one's own files from AVI or copy a disc in its entirety. If you are creating a VCD, it makes sense to burn an RW for evaluation before making one or more CD-R's for use. (Some standalone players which will not take write-once media will play erasable.)
E-mail me at cdrecording@mrichter.com
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