International video standards conversion presents a larger challenge to international viewing than does region coding. Video standards conversion is active, while circumventing the region coding system is passive.
Video conversion requires an active process for conversion to take place, whereas bypassing region codes is simply a matter of allowing information to pass through. Moreover, standards conversion is not a trivial task, nor is it one that either works or does not.
Due to the independent growth of standards across the globe, it is not a given that a video product produced in another country will work with your local playback devices. For this reason it's critical to involve a professional in the management of international video standards conversion.
There are many differences in the international community regarding video standards. It's not merely a matter of screen size, but scan rate (the rate at which lines are drawn to the screen), color considerations and even media type (size of tape of means of reading digital media). All of these factors go into the process of converting video from one international standard to another.
A variety of methods of converting video signals from one standard to another exists, and the level of quality will vary with these methods. Not surprisingly, the methods that yield the highest-quality conversion are also the most complex and thus the most expensive. This section provides an overview of how video standards conversion from PAL to NTSC works.
There are several parts to the process of converting VHS tapes formatted with international videotape standards, such as PAL, N-PAL, M-PAL, SECAM, and MESECAM, to NTSC standards, or vice-versa: converting from any supported format to a VHS videotape recorded in an international standard. In general standards conversion (a PAL videotape to an NTSC monitor, for example), there is a process of converting the color. Even in these conversions, the color portion of the conversion is relatively simple because the color elements of the PAL standard are based on and are an improvement of the older NTSC standard. The PAL system does have more color information, resulting in a more accurate and stable color picture. Since it is similar in nature to the NTSC color system, however, little work is needed to convert the color system.
Converting the number of scan lines in a field from PAL to NTSC involves fitting the 312 scan lines in a PAL field into the 262 scan lines in an NTSC field. The methods vary, as does the quality of their results. There is no "perfect" or "correct" video standards conversion, only processes that yield better or worse results. |
