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-   -   Capturing Uncompressed 24p from the HD-100 (https://www.dvinfo.net/forum/jvc-gy-hd-series-camera-systems/80680-capturing-uncompressed-24p-hd-100-a.html)

Thomas Smet December 5th, 2006 09:03 PM

Through component there is no way to capture just 24p or 30p. It all has to come out as 60p. There is just no way around it with an analog connection. The Varicam actually builds flags into the SDI stream that tell the capture device which frames to scrap. This is why odd framerates such as 23p and 33p work with the Varicam. Sadly any sub market HD camera is going to have this issue with uncompressed/low compressed output. The Canon series will send out 60i from the component/SDI ports with 3:2 pulldown and the JVC will send it as 60p with 3:2 pulldown. Even the HVX200 would have the same issue if you wanted to capture live uncompressed from the component output. Everything would either come out as 60p or 60i depending on what mode you were in. Sadly at this stage if we want uncompressed quality 24p we will have to use tools to extract the raw frames or edit as a 60i or 60p video.

It sure would have been nice if JVC could have added the Panasonic flavor of flagging the frames across SDI with the HD250.

I'm not sure about the AJA hardware but I thought the Blackmagic cards could capture as 30p since all the capture tool has to do is drop every other frame. No matter how the signal is coming in if you drop every other frame you will end up with 30p. This however does not help for 24p.

This is why in many ways I still prefer to work with 25p if possible. 25p is a lot easier to pull out of a 50p stream then 24p is. In the case of 50i you can just capture 25p material as 50i so no processing needs to be done at all except for the 4% audio shift and frame shift in the end.

Jim Fields December 6th, 2006 11:17 PM

Might sound stupid, but....

People find ways to Hack and XBox to rip DVD's and Play ripped games, or a PS3, or hack a cell phone to shoot a laser.

Point is, is this a hardware limitation, or a software limitation. If it is software limitation, how about writing new software for the camera? Software gets created to produce an uncompressed HD stream.

Me, I love my camera. If I want true 24P, I will rent a film camera. I am very happy with what I have now.

Steve Oakley December 7th, 2006 10:26 AM

Quote:

Originally Posted by Thomas Smet
Through component there is no way to capture just 24p or 30p. It all has to come out as 60p. There is just no way around it with an analog connection. The Varicam actually builds flags into the SDI stream that tell the capture device which frames to scrap. This is why odd framerates such as 23p and 33p work with the Varicam. Sadly any sub market HD camera is going to have this issue with uncompressed/low compressed output.Sadly at this stage if we want uncompressed quality 24p we will have to use tools to extract the raw frames or edit as a 60i or 60p video.

It sure would have been nice if JVC could have added the Panasonic flavor of flagging the frames across SDI with the HD250.

.

FCP can remove pulldown after capture Tools->remove advanced pulldown, so can cinema tools, but you'll still have to capture 59.94, which eats a huge amount of drive space considering that to start, its 50% or higher duplicate data. very much a stupid and time consuming workaround. its not practical for long form projects at all. I think Kona can strip out 3:2 PD... I'll have to try it.

yes they could of even of put the data in analog, as part of VITC, which I think the panasonic gear also does.


Steve Oakley

William Hess December 7th, 2006 11:18 AM

HD100 Camera Head Operates At 48p in 24p mode
 
Sorry for butting in, however I am 99.99% sure that the JVC HD100 camera head outputs a 48p component stream in 24p mode and a 60p component stream in 30p mode. This has been mentioned in many threads over the months. For example:

http://www.dvinfo.net/conf/showthread.php?t=65949

"The HD100 and HD101 are both capable of capturing, encoding and recording 24P, 25P, & 30P as 720P HDV to tape. The camera is also capable of capturing and outputting 48P, 50P and 60P live as 720P to the analog component outs."

So while 24p is recorded to tape in a 60p stream with repeat flags, the head should be outputting 48p out of the components.

Thomas Smet December 7th, 2006 11:36 AM

Quote:

Originally Posted by William Hess
Sorry for butting in, however I am 99.99% sure that the JVC HD100 camera head outputs a 48p component stream in 24p mode and a 60p component stream in 30p mode. This has been mentioned in many threads over the months. For example:

http://www.dvinfo.net/conf/showthread.php?t=65949

"The HD100 and HD101 are both capable of capturing, encoding and recording 24P, 25P, & 30P as 720P HDV to tape. The camera is also capable of capturing and outputting 48P, 50P and 60P live as 720P to the analog component outs."

So while 24p is recorded to tape in a 60p stream with repeat flags, the head should be outputting 48p out of the components.

I'm not sure if any capture cards support the 48p however. I think the cards are mostly limited to 60p with 50p just starting to be used. I'll have to look into that.

Paul Jefferies December 7th, 2006 12:02 PM

Could someone tell me what it outputs in 25p mode?

Thomas Smet December 7th, 2006 01:22 PM

50p. This is much easier to deal with then uncompressed 24p since all you have to do is drop every other frame. It does still however take up twice as much space. Maybe there is a way with Blackmagic cards to only capture every other frame.

Thomas Smet December 7th, 2006 01:25 PM

Quote:

Originally Posted by Steve Oakley
FCP can remove pulldown after capture Tools->remove advanced pulldown, so can cinema tools, but you'll still have to capture 59.94, which eats a huge amount of drive space considering that to start, its 50% or higher duplicate data. very much a stupid and time consuming workaround. its not practical for long form projects at all. I think Kona can strip out 3:2 PD... I'll have to try it.

yes they could of even of put the data in analog, as part of VITC, which I think the panasonic gear also does.


Steve Oakley

I'm pretty sure VITC is only on SDI. According to the Blackmagic website only SDI on the cards will read VITC. Based on that only the HD250 could be made to even use VITC. Most people that use a Varicam would only use SDI and never even think of using component so why even think of putting VITC in component?

Stephen L. Noe December 7th, 2006 03:58 PM

Quote:

Originally Posted by William Hess
Sorry for butting in, however I am 99.99% sure that the JVC HD100 camera head outputs a 48p component stream in 24p mode and a 60p component stream in 30p mode. This has been mentioned in many threads over the months. For example:

http://www.dvinfo.net/conf/showthread.php?t=65949

"The HD100 and HD101 are both capable of capturing, encoding and recording 24P, 25P, & 30P as 720P HDV to tape. The camera is also capable of capturing and outputting 48P, 50P and 60P live as 720P to the analog component outs."

So while 24p is recorded to tape in a 60p stream with repeat flags, the head should be outputting 48p out of the components.

It's been reported however it's false (at least on my system).

I'm capturing 24p uncompressed from the components and it still is a 59.94 stream coming out of the component's when the camera is in 24p mode.

Daniel Patton December 7th, 2006 04:13 PM

Quote:

Originally Posted by Alex Bowles
Thanks Stephen

Unfortunately, I don't have the capture path I'm after set up yet, but where I'm going is this:

SDI out from the JVC, into a BlackMagic card (with a Miranda box for an A/D conversion, if necessary) with the card applying the 3:2 pulldown to extract 24p from the 720p60 signal coming out of the camera, compressed at 2:1 (lossless) before going to disk. Capture is managed via FCP.

Has anyone else tried this out?

A

Alex,

You can do this with the Blackmagic by using the 24P Varicam settings in FCP with SDI & Blackmagic, as uncompressed... with the following catch.

As Thomas mentioned, you are now talking about using the HD250 since it has SDI, the HD100 & HD200 do not. If you are serious about the uncompressed route and want the quality, then stay clear of the component from the JVC at any cost, the image is simply too soft IMO even compared to the HDV/tape. All you gain is 4:2:2 from the process, and it's just not worth the loss in detail.

Beg, barrow, rent or steal the HD250 with it's SDI, or simply stick with the HDV. Otherwise you may learn the hard way that doing a conversion from component (if I'm reading this right) to SDI is going to disappoint and be an even bigger waste of money.

With the Blackmagic and HD250 at a true 24P stream you no longer need a $$ fast drive array, or nearly as much storage due to a lower data rate, so that's another plus that offsets the cost (some).

We have some true 24P test clips somewhere from the HD250 that was on loan from JVC that we ran through our Decklink Multibridge. Nothing with much real movement though, so I doubt it's of much interest if looking at motion blur.

Good luck regardless!! Peace!

Steve Oakley December 8th, 2006 12:38 AM

VITC came from the analog world. it got really popular from the BVW series VTR's that could record it without needing any external boxes to insert it into the signal. I've got some 1" with VITC too :)

anyways, did some research and indeed I was right. 720 always runs at 59.94 and lower frame rates are simply putting duplicate frames into the stream.

so maybe tomorrow I'll look at analog capture again with my kona LH if I can get the time.


Steve Oakley

Alex Bowles February 25th, 2007 12:20 PM

Test Results
 
Using a BlackMagic Decklink HD Extreme, I'm able to capture the uncompressed output from my HD-110 direct to disk.

The issue I've run into is that I'm stuck with 60/24 capture.

The camera allows the user to set the clock-speed of the CCD to 60 or 50 Hz. FCP simply won't see the devise if it's outputting at 50Hz. When set to 60 Hz, the data captures, but it's in a 24 fps Quicktime. I've not found any way to control this. And of course, it's all 60 frames, so playback is all slo-mo. Very nice slo-mo, but still slo-mo.

Speeding it up by 250% brings it back to realtime, but this isn't a very elegant way to capture data. And you still don't have sync sound.

Wondering if the 'Varicam flag' featured in the HD-250 is part of the solution. Or are people making this work with the HD-110?

Brian Mills February 25th, 2007 02:40 PM

Cinema Tools?
 
Have you tried Apple's Cinema Tools to convert the 60P footage back to its original 24P? I think I heard someone say this was the intended work-around, but I've never tried it. Please post any results you find, as I have a 110 and will soon be getting a Decklink card for uncompressed capture myself. Thanks

Steve Oakley February 25th, 2007 07:52 PM

Quote:

Originally Posted by Alex Bowles
Using a BlackMagic Decklink HD Extreme, I'm able to capture the uncompressed output from my HD-110 direct to disk.

The issue I've run into is that I'm stuck with 60/24 capture.

The camera allows the user to set the clock-speed of the CCD to 60 or 50 Hz. FCP simply won't see the devise if it's outputting at 50Hz. When set to 60 Hz, the data captures, but it's in a 24 fps Quicktime. I've not found any way to control this. And of course, it's all 60 frames, so playback is all slo-mo. Very nice slo-mo, but still slo-mo.

Speeding it up by 250% brings it back to realtime, but this isn't a very elegant way to capture data. And you still don't have sync sound.
?

I would highly suggest starting with the proper preset for 720P capture. if you need to change the codec, you can. I'd also suggest trashing FCP prefs too, and finally reinstall the BM drivers of the most recent vintage and FCP updates, ect.

finally, if you are shooting 24p with a 110 north american (60hz) native model, you should then be able to capture using the 720P 59.94 uncompressed preset. 24(23.976) will come in at 59.94. there are no metadata bits in the analog to flag frames like the varicam does.

it should just work


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