3D film

Beginnings film studio

Typical major film studio components

Today film studio

The Walt Disney Company

20th Century Fox

Universal Studios Hollywood

Universal Pictures


Republic Pictures

3D Technology


RealD Cinema


DreamWorks Animation






DV is a format for storing digital video.
It was launched in 1995 with joint efforts of leading producers of video camera recorders.
The original DV specification, known as Blue Book, was standardized within the IEC 61834 family of standards. These standards define common features such as physical videocassettes, recording modulation method, magnetization, and basic system data in part 1. Part 2 describes the specifics of 525-60 and 625-50 systems. The IEC standards are available as publications sold by IEC and ANSI.
Prior to the DCT compression stage, chroma subsampling is applied to the source video in order to reduce the amount of data to be compressed. Baseline DV uses 4:1:1 subsampling in its 60 Hz variant and 4:2:0 subsampling in the 50 Hz variant. Low chroma resolution of DV (compared to higher-end digital video formats) is a reason this format is sometimes avoided in chroma keying applications, though advances in chroma keying techniques and software have made producing quality keys from DV material possible.
Like DVCPRO, DVCAM uses locked audio, which prevents audio synchronization drift that may happen on DV if several generations of copies are made.
When recorded to tape, DVCAM uses 15 m track pitch, which is 50% wider compared to baseline. Accordingly, tape is transported 50% faster, which reduces recording time by one third compared to regular DV. Because of the wider track and track pitch, DVCAM has the ability to do a frame-accurate insert edit, while regular DV may vary by a few frames on each edit compared to the preview.
DVCPRO Progressive was introduced by Panasonic for news gathering, sports journalism and digital cinema. It offered 480 or 576 lines of progressive scan recording with 4:2:0 chroma subsampling and four 16-bit 48 kHz PCM audio channels. Like HDV-SD, it was meant as an intermediate format during the transition time from standard definition to high definition video.
Tape-based DV variants, except for DVCPRO Progressive, do not support native progressive recording, therefore progressively acquired video is recorded within interlaced video stream using pulldown. The same technique is used in television industry to broadcast movies. Progressive-scan DV camcorders for 60 Hz market record 24-frame/s video using 2-3 pulldown and 30-frame/s video using 2-2 pulldown. Progressive-scan DV camcorders for 50 Hz market record 25-frame/s video using 2-2 pulldown.
Consumer-grade DV camcorders capable of progressive recording usually offer only 2-2 pulldown scheme because of its simplicity. Such a video can be edited as either interlaced or progressive and does not require additional processing aside of treating every pair of fields as one complete frame. Canon and Panasonic call this format Frame Mode, while Sony calls it Progressive Scan recording. 24 frame/s recording is available only on professional DV camcorders and requires pulldown removal if editing at native frame rate is required.


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