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Why don't camcorders record a kind of .hdv to an internal HDD?, Instead of using a variety of other encodings like AVCHD
mcpancakes
post Jan 22 2010, 05:05
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I've been reading the wikipedia articles on DV and HDV, and from what I can gather, the DV recorders out there either 1) record a raw DV format stream to tape, 2) save a raw .dv file copy of the stream, or 3) pack it in one kind of container or another. from what I can gather, the case is not similar for HDV. there's the HDV raw streams that are saved to tape, but if you save to file-based storage like an on-camera HDD, the camera does not simply put a raw HDV stream nor pack the raw stream in a container, but rather uses a completely different method of encoding. is this correct? if so, why?
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Arnold B. Kruege...
post Mar 1 2010, 14:45
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QUOTE (mcpancakes @ Jan 21 2010, 23:05) *
I've been reading the wikipedia articles on DV and HDV, and from what I can gather, the DV recorders out there either 1) record a raw DV format stream to tape, 2) save a raw .dv file copy of the stream, or 3) pack it in one kind of container or another. from what I can gather, the case is not similar for HDV. there's the HDV raw streams that are saved to tape, but if you save to file-based storage like an on-camera HDD, the camera does not simply put a raw HDV stream nor pack the raw stream in a container, but rather uses a completely different method of encoding. is this correct? if so, why?


It's all about space and the state of the art and salability.

The DV tape format actually stores a lot of data on that little cassette. A standard 1 hour mini DV tapes is said to hold about 10 GB. This is pretty impressive given the age of the technology. And when the tape gets full, you just pop another one in, that may have cost you less than $10.

Uncompressed or lightly compressed HD video has a lot of data in it.

Nobody wants to pay the big bucks for a camcorder that can only handle a few minutes of video and then needs to be offloaded.
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2Bdecided
post Mar 1 2010, 16:02
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QUOTE (mcpancakes @ Jan 22 2010, 04:05) *
the camera does not simply put a raw HDV stream nor pack the raw stream in a container, but rather uses a completely different method of encoding. is this correct? if so, why?
Because when manufacturer X brings out an MPEG-4 based HDD camcorder, manufacturer Y would struggle to convince the market that their MPEG-2 based HDD camcorder was better (even though it may be).

IIRC there are some which do 24Mbps MPEG-4, which should be (probably now is) better quality than 25Mbps MPEG-2.

Cheers,
David.
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smok3
post Mar 1 2010, 17:43
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QUOTE (Arnold B. Krueger @ Mar 1 2010, 14:45) *
Uncompressed or lightly compressed HD video has a lot of data in it.

Nobody wants to pay the big bucks for a camcorder that can only handle a few minutes of video and then needs to be offloaded.


HDV is not slightly compressed, actually the bitrate is the same as with the DV, sony (for example) offers an external battery powered HD that attaches to firewire out and records just fine into hdv.

the problem is that while DV was actually kinda acceptable quality for an SD era, HDV is not for a HD era...., but thats for another topic.

QUOTE
Nobody wants to pay the big bucks for a camcorder that can only handle a few minutes of video and then needs to be offloaded.


totally wrong. http://www.red.com/

This post has been edited by smok3: Mar 1 2010, 17:47


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