P2 (storage media)

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DVCPRO P2 (P2 is short form for "Professional Plug-In") is a professional digital video format introduced by Panasonic in 2004, and especially tailored to ENG applications. It features tapeless (non-linear) recording of DVCPRO or DVCPRO50 streams on a solid state flash memory card. DVCPRO HD recording on P2 is possible with the Panasonic AG-HVX200. The P2 Card is essentially a RAID of SD memory cards with an LSI controller tightly packaged in a die-cast PCMCIA enclosure, so data transfer rate increases as memory capacity increases. The system includes cameras, decks as drop-in replacement for VCRs, and a special 5.25" computer drive for random access integration with NLE systems. The cards can also be used directly where a PCMCIA slot is available, as in most notebook computers, as a normal disk drive, although a custom software driver must first be loaded.

Since the memory capacity of the P2 card is relatively low (as of January 2006, 2GB [4×512MB cards], 4GB [4×1GB SD cards] and 8GB [4×2GB SD cards] cards are available), cameras, decks and drives have multiple slots, with the ability to span the recording over all slots. This way, effective recording time is multiplied, allowing up to 80 minutes on five 4GB cards in normal DVCPRO 25 mode. Cards are recorded in sequence, and when a card is full, it can be swapped out while another card is recording, allowing unlimited recording time assuming an adequate supply of cards is available. If a card is partially full, the deck will record only until it is full. Unlike tape, old video cannot be recorded over accidentally. Old footage must be manually deleted.

The first pieces of equipment released by Panasonic which use the P2 format included the AJ-SPX800 (a 2/3" broadcast camcorder for ENG and EFP applictions), the studio recorder AJ-SPD850, the AJ-PCD10 offload device (basically, a five-slot PCMCIA reader with USB interface designed to fit a 5-1/4" IT systems bay), and the memory cards themselves - AJ-P2C004 (4Gb) and AJ-P2C002 (2Gb). The AG-HVX200 consumer/semipro camcorder is not, despite common belief, the first P2 device, but it is the first to offer multi-rate standard and high definition recording.