High Definition Video (HDV) camcorders. What are they?

[SeeMoreDigital]

While scanning the forum I've not seen any detailed information about this emerging technology so I thought I'd provide some.

In July 2003 JVC, Canon and Sony got their heads together and announced a new consumer camcorder format called HDV. Although it's not an official standard it may indeed become one based on their combined proportion of sales in the MiniDV camcorder market.

Sufficed to say the HDV format has been designed to be backwards compatible with MiniDV, meaning that it uses the same mini DV tapes (although a higher grade tape is available) running at the same speed and track pitch. It's hoped (by the three main players) that by keeping the same basic tape specification ad transport system, it will be easier for all manufacturers to adopt the HDV format.

All HDV camcorders are able to shoot video to the conventional miniDV.avi standard (5:1 compression in 4:2:0 for PAL or 4:1:1 for NTSC). But where HDV differs from miniDV is it's ability to generate high definition video directly to Mpeg2 in 4:2:0 for PAL and NTSC. And in doing so, up to four times more information can be stored on the same 60min miniDV tape, while still maintaining a min 60min run-time.

HDV includes a variety of scan modes (which manufacturers can implement at their own volition). The progressive-scan mode can be set to 25,30,50 or 60 frames per second (fps) and includes 1080 interlaced-scan modes at 50Hz or 60Hz, using an aspect ratio of 16:9 (4:3 and 16:9 is available in DV.avi mode). The Mpeg2 data rate runs at 19Mbps (2.375MBps) for 720p or 25Mbps (3.125MBps) for 1080i and error correction is spread over multiple tracks instead of one track. Users can even switch between HDV and DV while recording and 1080i images can be down-converted to 576i, for viewing via a conventional analogue TV.

Audio is captured to just two channels (stereo) using Mpeg1 layer2 at a bitrate of 384Kbps. The sampling rate/size is 48kHz/16 bit

HDV camcorders output their streams via FireWire (MPEG-2TS). Progressive captures are outputted in the form of an TS stream. Interlaced captures are outputted in the form of an packetised elementary stream.

When it comes to HDV camera's, current offerings are described as being "semi-professional" and are therefor quite large.

Here's what the JVC GR-PD1 looks like: -

http://img62.exs.cx/img62/6119/JVC_GR-PD1.jpg

And here's what the Sony HDR-FX1 looks like: -

http://img58.exs.cx/img58/1425/Sony_HDR-FX1.jpg



Cheers


Please feel free to move this post as required...

[guada]

Hello SeeMoreDigital, :)

I have some questions.
Do you have an idea of its storage capacity on a DV cassette in SP mode 60 minutes for a format 720p?
Does HDV cassettes exist?
I suppose that this range goes evolved, also one can think that it will be equipped shortly with a disk (presents already on some range of SONY) of bigger capacity.

The MODS would probably agree to him concerning pure storage.
In short, it is probably the fiction.
When, I sometimes think that the fiction melts in the reality.

[SeeMoreDigital]

Hi guada,

Just as with conventional miniDV you get a min 60 minutes recording time per tape. As far as I am aware there is no LP mode when the camcorder is set to Mpeg2.

With regard to the "higher grade" tapes, yes they do exist. But they are only available from specialist outlets - the same thing happened when high grade S-VHS tapes were launched!

A professional version of HDV is already available, using hard-disks. MiniDV tape is being used because it's affordable (disposable) and should help kick start the format into the home market.

Simplistically, given that a typical miniDV tape runs for 63 minutes and consumes around 225MB per minute. Each tape is able to store around 14,200MB (14GB).


Cheers

[guada]

Thank you for your explanations.

[communist]

Although not overly 'new' - I'm really looking forward to HDV as its described as HD for the masses. The main problem is the lossy and not so easy to edit MPEG2 compression that HDV employs.
If you google around a bit you might be able to find wmv compressed samples which can give you an idea about HDVs pros and cons:
- High Resolution!
- low temporal resolution and no film-like motion-blur resulting in jerky motion - you will notice that they carefully selected scenes to hide this as good as possible ;)

Its still very impressive what can be done and from what I have gathered a 60p/50p fps mode is not doable yet since the MPEG encoder chip (SuperEncIII or something like that) that (JVC) uses isnt fast enough and also uses quite a lot of power.

Some Links:
http://www.geocities.com/mammacow3/lorinspeak.htm
http://bg.videosystems.com/ar/video_nab_shoots_hd/
http://www.electronicstalk.com/news/hac/hac106.html

[theReal]

Is an MPEG2 data-rate of 25Mbps really sufficient for high quality 1080i pictures?
Also, what kind of MPEG2 is it? Is it modified MPEG2 (I-frame only) so it can be edited (I think so because the first camcorders to be launched are semi-pro models)?
Third question: who wants to give me one of these? ;) LOL

[SeeMoreDigital]

When I had chance to play with the JVC HDV camcorders, the 720p images certainly managed to hold up to expectations. And as I have a 42" HD plasma with 1366x768 pixels, I certainly wasn't about to loose much ;)

When it comes to editing the Mpeg2 stream, I don't know whether it's an I-frame only affair or a mixture of I and P-frames... Personally speaking, given the data-rate, I would be surprised to find that there were any b-frames in there..... So more research is needed.

Given that this form of Mpeg2 technology is in it's infancy and can only get better!

One thing is clear for me though... I would rather have a camcorder that encodes directly to miniDV tape, rather than microMV or even miniDVD... But as guada already mentioned, a hard disk would be better. Even if it had to be connected via FireWire.


Cheers

[Morbo]

Nice spec for Video,but wow...MPEG2 audio?!

Even DV is PCM,so is that confirmed?

At anyrate,another format is not what anyone needs at this point,especially since the next format of DVD-HD has yet to even
be marketed yet.

Probably will fill the Porn industry's need though,great Picture,lousey sound.....lol

Cheers!

[communist]

Its MPEG2 (420) with I/P (and B?) compression, I-frame only would make it too useful for editing ;)
The first thing this is advertised for is for the masses and indi-film makers (who are supposed to fall for the mega resolution ;)
Also employing I-frame only compression would result in way higher bitrates and shorter recording times - something they certainly wouldn want for a consumer model.
And last but not least manufacturers still want to sell real HD cameras - so dont expect miracles but rather a step into the right direction.

I mean after all a camera that does 720p for $3k - now that certainly is going to have its problems but still think about it. Its similar to Panasonics DVX100 - though not a perfect camera when it was released it still delivered what they promised: REAL 24/30p on digital format (MiniDV) and that all for under $5k - AFAIK the next model that did real 24p was over $20k at that time.

[SeeMoreDigital]

And by the way, if any of you want to see how good (or bad) High-Def Mpeg2 video looks like...

For NTSC samples, look here: -

http://www.vasst.com/HDV/FX-1_images-Surfers.htm

And for PAL samples, look here: -

http://www.vasst.com/HDV/FX-1_images.htm


Cheers

[theReal]

I would rather have a camcorder that encodes directly to miniDV tape, rather than microMV or even miniDVD...

Of course - MicroMV or MiniDVD are not even worth considering...
What I'd want was something like HDV, only with higher bitrates and I-Frame only (at least something like MPEG IMX with 50mbit data rate).

However, I also heard that companies like Sony don't want to make the "mistake" again to release a consumer format which is so good that it can be used professionally. MiniDV as a consumer format was so good that it can be used for broadcast production. When on air over cable or antenna, the pictures from a Panasonic DVX100 can hardly be distinguished from a pro 2/3" CCD DVCAM camcorder - but the Panasonic costs ~3K while the pro camcorder costs ~20K...

--> conclusion: make HDV not good enough for the pros and they have to buy DigiBeta HD camcorders for 60-70K a piece... :sly:

[SeeMoreDigital]

Some of you may be interested in a bit of capturing software cafut has found: -

Originally posted by cafut
This might be bit off topic, but I am really happy I finally found a free tool to capture HDV material from my brand new Sony HDR-FX1. I had no opportunity to check with JVC JY-HD10 / GR-HD1, but it should work.

http://home.earthlink.net/~weathersix/CapDVHS_0306a.zip

This is a modified version suitably resizing fonts for English texts.
For an umodified CapDVHS version, please search the net.

In order to get the resulting MPG files opened by VirtualDub, I used an AviSynth script consisting of just one line:
DirectShowSource("filename.mpg")

I may be late with this, but if could help just someONE it's great for me ...
Nice one... many thanks.

[kolak]

If somebody looking for HDV capturing and editing software here're some infos:

http://www.vasst.com/HDV/hdv-FAQ.htm