The HDV format was developed by JVC and Sony Corporation. The format was also initially supported by both Canon Inc. and Sharp Corporation. All four companies are potential manufacturers of HDV hardware, but Sharp has not manufactured any HDV cameras at this time. HDV has since been supported by several other companies, including Apple, Avid, Canopus, Sony Media Software, and Ulead. In 2007 Constructive Lab developed a solution allowing HDV to be securely transmitted over low bandwidth networks.HDV was designed to offer existing video production environments a cost-conscious upgrade path from standard-definition (SD) to high-definition (HD) video. HDV recorders are offered to both the consumer and entry-level video production market. Consumer models are sold to the mass consumer market, competing with other camcorder product used for home, travel and vacation video.
HDV video can be edited on a modern desktop/laptop PC, and burned and distributed on home-video DVDs. Prosumer models are designed for individuals and organizations specifically interested in video production, and are generally sold to amateur videographers, local production and marketing agencies, etc.
HDV video can also be imported into a professional environment, although the quality of the product limits this use to news and other non-studio applications.
HDV is based on MPEG-2 video, which compresses data both within each frame (intraframe/spatial compression) and between frames (interframe/temporal compression). This is the same type of compression used for DVD video and many network TV broadcasts, and allows HDV to achieve high spatial resolution at low data rates compared to other HD recording formats. HDV 1080i uses a recording data rate of 25 Mbit/s (3.125 MB/s) while HDV 720p records at 19.7 Mbit/s (2.46 MB/s) -- compared to data rates of 50-100 Mbit/s and up for other HD formats.
For audio, HDV uses (MPEG-1 Layer 2) compression to reduce the audio bitrate to 384 kbit/s, compared to 1536 kbit/s for DV video and 1,378 kbit/s for audio CDs. This makes HDV audio less desirable for situations where sound quality is critical, but MPEG-1 audio at 384 kbit/s is considered 'perceptually lossless.' For general video recording with an on-camera microphone, HDV audio is not a significant limiting factor.
It is important to view HDV's compression limitations in the proper context. Other HD codecs using lower compression ratios need more bandwidth and storage capacity for a given amount of video, requiring significantly more complex and expensive recording solutions. For example, Panasonic AG-HVX200 camera uses memory cards which can cost over $50 per minute of recording capacity, compared to a few dollars per hour for Mini-DV tapes. This cost differential has helped make HDV a popular HD recording format for consumers, independent videographers and low-budget TV programs.
HDV is based on MPEG-2 video, which compresses data both within each frame (intraframe/spatial compression) and between frames (interframe/temporal compression). This is the same type of compression used for DVD video and many network TV broadcasts, and allows HDV to achieve high spatial resolution at low data rates compared to other HD recording formats. HDV 1080i uses a recording data rate of 25 Mbit/s (3.125 MB/s) while HDV 720p records at 19.7 Mbit/s (2.46 MB/s) -- compared to data rates of 50-100 Mbit/s and up for other HD formats.
For audio, HDV uses (MPEG-1 Layer 2) compression to reduce the audio bitrate to 384 kbit/s, compared to 1536 kbit/s for DV video and 1,378 kbit/s for audio CDs. This makes HDV audio less desirable for situations where sound quality is critical, but MPEG-1 audio at 384 kbit/s is considered 'perceptually lossless.' For general video recording with an on-camera microphone, HDV audio is not a significant limiting factor.
It is important to view HDV's compression limitations in the proper context. Other HD codecs using lower compression ratios need more bandwidth and storage capacity for a given amount of video, requiring significantly more complex and expensive recording solutions. For example, Panasonic AG-HVX200 camera uses memory cards which can cost over $50 per minute of recording capacity, compared to a few dollars per hour for Mini-DV tapes. This cost differential has helped make HDV a popular HD recording format for consumers, independent videographers and low-budget TV programs.
HDV has some similarities to the more professional XDCAM-HD format, but the latter uses higher data rates for both video and audio signals.
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