DV
(1) (Digital Video) A generic term for capturing and/or editing video in the digital domain.
(2) (Digital Video) A digital videotape format that was introduced in 1995 for camcorders. Because of its high quality, DV has become widely used in both consumer and professional applications with Sony and Panasonic introducing high-end variants (DVCAM, DVCPRO).
DV and MiniDV Cassettes
DV uses 1/4" (6.35mm) metal evaporated tape and comes in two cassette formats: standard full-size DV cassettes (125x78x14.6mm) that hold three hours of video and one-hour MiniDV cassettes (66x48x12mm). The small MiniDV cassettes greatly enabled camcorders to shrink to handheld proportions.
Compression and Specifications
Depending on the motion content of the scenes, DV provides about a 5:1 compression. It uses the same DCT algorithm as MPEG for compression, but it is easier to edit because each frame is compressed independently without relying on the frame before it.
Based on the IEC 61834 standard, DV tape moves at a constant rate of 18.8mm per second, providing a data rate of 25 Mbps. The newer SMPTE 314 standard supports 25 Mbps and provides 50 Mbps for studio use.
DV machines record a YCbCr 720x480 frame for NTSC and a 720x576 frame for PAL/SECAM. DV tapes can be played back on DV, DVCAM and DVCPRO tape decks; however, MiniDV cassettes require an adapter for DVCPRO machines. Note: DV is not related to DVD, although both use YCbCr digital recording. See HDV, DVCAM, DVCPRO and D9.
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| DV and MiniDV Cassettes |
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| The full-size DV cassettes holds three hours of digital video. The small MiniDV cassettes were designed for today's miniature camcorders and store only one hour of video. |
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| All Sizes |
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| DV camcorders range from tiny handhelds (top) that cost less than a thousand dollars (2005 prices), to prosumer models in the $4,000 to $10,000 range (middle), to professional units that cost $50,000 and more (bottom). |