COMPRESSION – TV – Film – Radio
System of reducing or compressing digital data for transmission or storage. Works by selecting and filtering out some of the less useful information in a digital signal. Visual images require an enormous amount of storage space that would exceed the space available on a manageable system like a videotape, CD or DVD. To manage this amount of data and to record these images and sound onto tape, disc or hard disk, several systems of compression have evolved. Compression works by SAMPLING the pictures and sound in a particular digital process. This can be very complex depending on the quality required for the final product. Several compression systems are used in television transmission and production. Many editing systems use JPEG compression. MPEG-2 provides much higher compression ratios and is used in transmission systems and DVD.
