Grass Valley PROFILE FAMILY v.2.5 - Manual (Page 22)

Chapter 1 Introducing the Profile Family
22 Profile Family
An I-frame (also known as an I-picture or Intra-picture) is analogous to a single
motion JPEG frame, where all data required to display a frame is stored in one
picture. A P picture (also called a predictive picture) uses a motion vector to
predict what will happen in the next frame and contains only the changed data,
rather than passing along another complex frame of video. In addition, a
B picture (known also as a bidirectional picture) relies on data from both
backward and forward motion vectors to determine how a future frame will be
composed. In general, the longer the GOP, the more efficient your MPEG video
stream will be.
Table 1 compares the capabilities of the PDR 100 and PDR200/300. The
optional products supported by these disk recorders are listed here:
• MPEG encoder/decoder board (optional PDR 200, standard PDR 300)
• Fibre Channel interface board
• Video mix effects board
• PDX 103 and PDX208 Profile Disk Expansion Units
• PAC 208 and PAC216 Analog/Digital Audio Interface chassis (PDR 200/300)
• XLR216 and BNC 216 Digital Audio Interface chassis (PDR 200/300)
• PRS200 and PRS250 Profile RAID Storage Systems
• PLS20 and PLS200 Profile Library Systems
• PRC100 Profile Control Panel unit
• LVS100 Live Controller
• Profile VideoGateway
• CD-ROM Drive
• Profile Tool Box Editor software
• Profile Tool Box List Manager software
• Profile TimeDelay application software