As Video CD is a very new technology, it is likely that many you are using the format for the first time. In the same way that you encounter picture problems with VHS tape recordings, you can encounter comparable problems in the VideoCD format. This section describes various symptoms and their causes.
Picture display problems can be internal to the quality of the pictures on the VideoCD. Not all VideoCDs have the same picture quality, and thus the resulting picture quality al playback may not be constant for all VideoCDs.
Macro-blocking:
Also known simply as 'blocking' or 'jagging', is caused by a lack of bits (binary digits) to store all the information, and happens when the VideoCD movie is created. The area of the picture for which there is insufficient information (bits) will be displayed as simple 8x8 or 16x16 blocks.
Unreal stillness:
This is when an object (such as a tree in the background) appears to absolutely motionless. This can happen during VideoCF creation, where the object is moving so slightly as for the motion to be ignored by the movie conversion process.
Digital rain:
This term describes a number of undesirable picture effects. One example of this is a small stationary object that appears in one frame, then disappears for a few frames, then reappears. This and other effects tend to be more apparent in earlier VideoCDs than ones more recently created.
Mosquitoes:
This effect can occur especially at the edges of moving objects, due to the number of bits of data concentrated about the point of movement. If can give the impression of a heat-haze or fuzziness in the picture.
The picture quality of VideoCDs made in America can vary from those made in Europe. American manufacturers favour sharper image, which can be clearer but be more prone to the above problems. European manufacturers favour a softer image, which can look more pleasing, and be less prone to the above problems.
Note:
A VideoCD cover that is not marked 'VideoCD' is not suitable for use with the Whitebook CD-ROM standard, and will therefore not be compatible with your system. Unfortunately, VideoCD labelling is not as consistent as it might be, so check with the sales staff before making your purchase.
