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-   -   Confused about which color space the HD110 uses (https://www.dvinfo.net/forum/jvc-gy-hd-series-camera-systems/78720-confused-about-color-space-hd110-uses.html)

Bill Ravens November 2nd, 2006 08:51 AM

Confused about which color space the HD110 uses
 
I'm a little confused about which color space is used/output by the HD110. My current understanding is that the analog CCD detects in 4:2:2 color space. That is reduced to 4:2:0 when recorded on tape or output, via firewire, to a hard disk recorder as an m2T file type. What color space is output via the component video connectors, assuming I'm running in HDV? If I digitize to HD-SDI, via an AJA or BMD card, do I retain the 4:2:2 color mapping?

Thanx for any help you can offer.

Bill R

John Miller November 2nd, 2006 09:19 AM

Based on the JVC blurb ( http://pro.jvc.com/prof/attributes/f...l_id=MDL101642 ), the analog component output is equivalent to 4:2:2.

Jiri Bakala November 2nd, 2006 10:18 AM

That is for live camera output only though - if the video is already on tape, it would be already compressed and I don't believe that that would be 4:2:2 anymore.

Daniel Weber November 2nd, 2006 11:26 AM

Live output is 4:2:2.

Recorded output is 4:2:0.

SDI live would be 4:2:2.

Dan Weber

Tim Dashwood November 2nd, 2006 01:38 PM

Quote:

Originally Posted by Bill Ravens
I'm a little confused about which color space is used/output by the HD110. My current understanding is that the analog CCD detects in 4:2:2 color space. That is reduced to 4:2:0 when recorded on tape or output, via firewire, to a hard disk recorder as an m2T file type. What color space is output via the component video connectors, assuming I'm running in HDV? If I digitize to HD-SDI, via an AJA or BMD card, do I retain the 4:2:2 color mapping?

Thanx for any help you can offer.

Bill R

You mean color sampling. Color space (601 vs 709) is something a little different.

For those who don't know, color sampling is a way for digital video to reduce the size of the encoded data and trick our brains so we don't notice. If you are interested, check out the amazing article Graeme Nattress has written.
http://www.lafcpug.org/Tutorials/bas...ma_sample.html

The point is that JVC never used to specify in their literature how much color information is actually being processed through the 12-bit D-A converter and output to the analog component out. They used the word "uncompressed" which in its literal meaning would suggest 4:4:4 color output, since even dropping the color sampling down to 4:2:2 is a form of compression. However, this new information on HD110 site would seem to contradict that.

The simple way to check would be to capture a resolution chart at 4:4:4 and check the resolution of the different channels.

Marc Colemont November 2nd, 2006 03:24 PM

A very nice article about the color sampling, Tim.
Here is another informative article for Color Space with a testchart showing the differences between 601 and 709. The colors are encoded through a different formula to store the values. 709 has a wider range for HD then the 601 SD when stored.
http://www.belle-nuit.com/testchart.html

Bill Ravens November 2nd, 2006 04:51 PM

yes, I meant color sampling. thanx for the interesting references. that's the first time i've seen a comparison of actual images, having read of the sampling method many times.

so, the remaining question in my mind is the actual and visible differences between 4:2:2 sampling as output over analog component YPbPr vs HD-SDI. I assume there is a quantization error difference...and that's a function of whether it was sampled at 8 bit or 10 bit depth? so, a camera like the HD250 with its HD-SDI output, samples at what bit depth?

Perhaps you can see where I'm headed with this....potential image differences between component output and A-D conversion then another D-A conversion for viewing.

Brian Luce November 6th, 2006 02:06 AM

One thing though, recording on a hd100 via component is not the most practical thing in the world. I'm not sure you can get the hardware onto a laptop so that leaves a desktop solution. Okay for studio shoots I guess... Then there's this cool thing called the Wafflean but it's not cheap. I think it's in the trillions of dollars.

Bill Ravens November 6th, 2006 08:07 AM

For awhile, I was thinking D-VHS, as a cheap substitute for the Waffian, however, the JVC DVHS decks record off of 1394 only. No component input. I can look at a really nice image on my HD monitor, staright from the component output on the camera. It seems somewhat odd that I can't also, record that signal on something at 4:2:2.

Carl Hicks November 6th, 2006 09:50 PM

Quote:

Originally Posted by Bill Ravens
For awhile, I was thinking D-VHS, as a cheap substitute for the Waffian, however, the JVC DVHS decks record off of 1394 only. No component input. I can look at a really nice image on my HD monitor, staright from the component output on the camera. It seems somewhat odd that I can't also, record that signal on something at 4:2:2.

Bill, the DVHS units have that limitation for two reasons that I can think of. First, in order to accept component HD input and record it to DVHS tape, the unit would need to have an MPEG encoder. A good encoder would drive up the cost significantly. Since this is format primarily designed for consumer HD playback, cost is a concern. Second, if the unit could accept component HD, then a pirate might could make some pretty good copies of commercially released films. And that would not sit well well with the folks that created those films.

Stephan Ahonen November 6th, 2006 10:58 PM

So, is anyone else as tired as I am of the movie industry treating their customers like criminals? With how incredibly easy it is to make a perfect digital copy of a DVD, I'm amazed that manufacturers are still trying to keep the analog hole closed with stuff like Macrovision that has negative effects on even legitimate users.

Daniel Patton November 7th, 2006 12:15 AM

Quote:

Originally Posted by Bill Ravens
so, the remaining question in my mind is the actual and visible differences between 4:2:2 sampling as output over analog component YPbPr vs HD-SDI.

I have been on a mission (like a rabid pitbull with a bad case of lock jaw), to find the answer to this very question.

Brian Luce November 7th, 2006 12:34 AM

Quote:

Originally Posted by Stephan Ahonen
So, is anyone else as tired as I am of the movie industry treating their customers like criminals?

I'm tired of it. I live in the philippines where it's very difficult to buy LICENSED dvd's. The price of a licensed dvd here is about 14 US Dollars. That represents about 2-3 days of salary for the average person here. That's like selling DVD's in the states for 600 dollars apiece. So the choices are 1) Never see movies 2) buy licensed dvd's and NOT feed your family, or 3) buy pirated every now and then, experience the magic of hollywood and still put rice on the table.

Alex Humphrey December 23rd, 2013 12:53 PM

Re: Confused about which color space the HD110 uses
 
So did anyone figure out if the JVC HD110 or family of camcorders have live output via component as 8 bit or 10 bit 4:2:2? I doubt very very very much it's 4:4:4. Anyway looking at a Samurai or Hypderdeck shuttle and a BlackMagic component to HDSDI converter for progressive signal to make my JVC a B camera for a Red Scarlet set of projects.

Paul R Johnson December 23rd, 2013 01:09 PM

Re: Confused about which color space the HD110 uses
 
Unless I'm being very stupid, there isn't any SDI out at all? Just composite and component analogue - plus firewire?
I've actually got one here I just pulled out to double check the sockets. The only digital output is via the firewire in switchable SD/HD


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