The ADV611/ADV612 are video encoders/decoders optimized for closed circuit TV (CCTV) applications. With the ADV611/ ADV612, you can define a portion of each video field to be at a higher quality level relative to the rest of the field. This "quality box" feature significantly increases compression of less important background details, while retaining the image's overall context. Additionally, the unique subband coding architecture of the ADV611/ADV612 offer many application-specific advantages. A review of the General Theory of Operation and Applying the ADV611/ADV612 sections will help you get the most use out of the ADV611/ADV612 in any given application.