Uncompressed FX1 / Z1 video

Christopher C. Murphy · January 28th, 2005, 06:40 AM

This is great information, you guys rock!

R Geoff Baker · January 28th, 2005, 09:48 AM

There is of course no chance that the component outputs are 'compressed', as analog outputs can't be -- but the question is has the output video been through the compressor & back out again -- is it a video output of decoded compressed video.

The simple answer seems to be no -- the component output from a live signal has not been compressed & decompressed ... however, it has been chroma down sampled so it is NOT pristine, 'uncompressed' in the sense that it is full quality.

Is there a gain if the component output is recorded using a higher quality recorder? Yes, in that there is no mpeg compression-decompression cycle and so no mpeg artifacting. But not as good as one could wish, and certainly not at the standard of 10 bit, 4:2:2 chroma.

GB

David Farland · January 29th, 2005, 01:57 AM

Don’t want to have arguments of what exactly what ITU standard or effective bit depth/colour space the live component out is until Sony Japan gets back to me with their engineering specification on the output.

Suffice to say capturing the component should remove mpeg artifacts, provide more robust editing/compositing which will ‘make’ the solution for a few people.

Is it 4:2:2 or 4:2:0….dunno.
Currently I’m looking at lithium-ion battery packs to power the capture system for a couple of hours. Pre-built battery arrays seem to range from $1000~1500. 100watts of battery weighs the same as a 3.5” disk unit (.6kg)probably need 6 plus controller boards for 2 hours shooting.
http://www.ocean-server.com/battery_packs.html.
Here is one supplier, Jon Crowell who knows his stuff when it comes to powering pc’s with batteries.

Thank you,
Dave Farland

Thomas Smet · February 3rd, 2005, 03:00 AM

Can the Z1 or FX 1 output from the component jacks a SD signal?

If so can it do it while shooting HD or does the camera have to be in DV mode?

The equipment costs wouldn't need to be as high then for storage. Many of us will still be doing SD projects for some time yet. You may also be able to get by with a fairly portable capture system.

You could use a high end laptop with Liquid Edition 6 pro. The LE 6 pro break out box connects to a USB2 port and captures from component uncompressed video. You would then only need to lug around a laptop, external G-raid, and the small LE6 bob.

David Farland · February 3rd, 2005, 06:40 PM

Very good idea Thomas but unfortunately you can't down-rez the component output to SD while recording in HDV. Sure you can on play back though.
Blackmagic sells it’s Decklink SD ($295) card which can down rez HD to SD but they recommend a HD platform http://www.blackmagic-design.com/site/65support.htm to support it. Not sure the minimum BM spec for a HD to SD capture only system as BM talk about their Decklink SD/ HD host system replaying HD footage in SD which wouldn’t be required here.

Thank you,
David Farland

David Farland · February 4th, 2005, 01:39 AM

Little more on the FX1 component out specification...

I asked Sony Japan the following question:-
What is the “ITU” standard that describes this component video output?

Sony replied:-
"The ITU standard is IT-R BT.709 and the factory says there is no recommended setting value of Digital Standard". (Sony Japan)

I'm waiting on more info......

Thanks you,
David Farland

Karel Bata · March 16th, 2005, 08:34 AM

A very interesting thread here...

And a little amusing too. Already we are getting used to the notion of employing a focus-puller on video shoots when the final product is meant for theatrical projection, and now we might even bring back the equivalent of the 'video-assist' playback operator!

So I took a look at what equipment playback operators currently use on film shoots.
This is the Omega deck (notice the removable hard drives)
The Digiclam
The Digi Combo
and a software version, Cinelog which can be used with proprietary hardware

So what you're aiming at is something not too dissimilar to one of these systems, right? But with a much higher throughput of data to allow the recording of component HD video.

You could also go a step further and build in some of the features that are on these systems such as mixing images (for critical line-ups) or variable speed playback.

Of course not everyone who owns an HDV camera would want one, nor - I think - would many HDV owners who'd have a use for it want it on every shoot. But it opens up the possibly of building a dedicated system (like some 35mm video assist operators already do) which can then be rented out to shoots.

In the UK this looks tempting...

As to this question of a high shooting ratio eating up disk space: well, again you go back to something like traditional film practices. You record everything, including rehearsals, log the 'selected takes' (the old continuity girl's job (I liked her - let's have her back!)) and then delete everything you don't want, making room for the next set up. Meanwhile - if you choose - you can also record everything using the camera's own tape transport to give you a back-up if you have a catastrophic failure on your hard drive recorder.

The director has to think in terms of a limited amount of memory - like a limited amount of film stock.

At the end of the day all the hard drives (which are removable) are taken to the editor.

Batteries: as long as it is understood that a mains supply is required either at studio / location, or via a genny, this is not an issue. But a proper reccy may be needed at each location by a competent electrician (big hotels for instance will exhibit a voltage drop and spikes when all the ovens go on mid morning). Some kind of mains supply cleaner or buffer (not my strong point) would be needed.

Karel Bata · March 16th, 2005, 09:24 AM

Just realised (oh silly me!) that of course the natural person to push the record button on this thing would be the sound recordist - so you don't need an extra member of crew after all.

(The poor Video Playback Op was always the first to go...)

Thomas Smet · March 17th, 2005, 05:12 PM

Would the chroma on the Z1 really be reduced right away? It seems like it would like many SD cameras but then I was thinking about how the camera would do it based on different output formats.

If you shoot HD you are getting 4:2:0
Now if you shoot DV or DVCAM you get 4:1:1

How can the camera switch the entire chroma output of the block based on what format you are using?

To me it seems if the chroma was reduced it was only be down to 4:2:2. This would be an easy point for the camera to get to either 4:1:1 or 4:2:0. If the block only did 4:2:0 where would the extra 1 come from for 4:1:1. The same is true if the block outputs only 4:1:1. The camera would have no way of bumping up to a 2 for 4:2:0.

I then thought well maybe during SD shooting the 0 turns to one since only 1 field is used. Well this would work for 480p mode but not regular everyday NTSC video. The two fields for 480i video would have to come from the same alternating fields from the HD block or else the fields would be interpolated. This means that unless the DV from the Z1 is only 4:1:0 the block must output 4:2:2.

I then thought about well maybe they kill the chroma near the component output. Well this would mean the signal would have to be run two different methods of chroma reduction based on the format. This seems like it would be hard and rather complex in a camera this small.

I could be wrong about all of this. Just my boring and rather useless thoughts on the subject.

R Geoff Baker · March 17th, 2005, 05:42 PM

4:1:1 and 4:2:0 are both the same 'amount' of chroma data -- one quarter the luma resolution -- just differently sited. 4:2:0 describes a chroma 'block' that is two pixels wide and two pixels tall; 4:1:1 describes a chroma rectangle that is four pixels wide and one pixel tall. This is a simplified description, but the salient fact is that both are derived quite easily from the same source chips, as they are -- but for a math trick -- the same.

IIRC PAL DV is already 4:2:0 instead of 4:1:1 -- this was in recognition of the 'extra' vertical resolution of PAL.

I believe the chroma downsampling is done at the imaging block before being sent to the encoder.

GB

Douglas Spotted Eagle · March 17th, 2005, 08:56 PM

I'll chime in here and say that anyone who'd buy an uncompressed card prior to NAB 2005 (between now and then) is acting out of impulse more likely than sensibility. You'll see several wonderful solutions at NAB. I'm testing one now....but can't say more. But it is sweet and stunning!

Thomas Smet · March 17th, 2005, 09:04 PM

So you are saying there is a software code hardwired into the camera that will change the way the chroma is output based on what format you are selecting? It then does this before hitting the encoder block? Wow if that is true SONY put a lot of effort into dumping down the live video from the camera as to not compete with the higher end gear. I know how the two chroma formats work, I just didn't think SONY would go to all that trouble to make the chroma dump thing complex enough to switch based on the format chosen.

R Geoff Baker · March 17th, 2005, 10:13 PM

No, I'm saying that the chroma downsampling is the same for both as far as the imaging block is concerned, and whether the downsampled chroma gets encoded as 4:2:0 or 4:1:1 makes no difference to the imaging block ... Either way the encoder gets a chroma downsampled source, how it chooses to manage that downsampled chroma becomes a codec choice.

GB

Alex Raskin · March 8th, 2006, 12:02 PM

Dustin, David et al:

With Decklink HD + Decklink Multibridge... have you had a chance to compare the quality of the video captured off Sony's Component out vs. MPEG (firewire/tape)?

Does the improvement in quality warrant a $2,600 extra hardware cost?

Most importantly, have you seen an improvement in green screen keying? (Any chance of screen grabs...)

Alex Raskin · April 3rd, 2006, 11:20 AM

OK, seem slike no-one has implemented this yet.

So I decided to bite the bullet and build a uncompressed ingest system.

(Thanks to everyone and especially David Farland for inspiration and info!)

Results and MPEG vs Uncompressed HD comparison photos are posted on my site: www.PrimeHD.com

I'm now looking for a Varicam to check if our system works with it, in practice. If you have a Varicam in NY or Northern NJ area, please let me know (my web site has a contact form...)

January 28th, 2005, 06:40 AM	#16
Christopher C. Murphy Trustee Join Date: Sep 2003 Location: Boston, MA Posts: 1,707	This is great information, you guys rock! __________________ Christopher C. Murphy Director, Producer, Writer

March 17th, 2005, 08:56 PM	#26
Douglas Spotted Eagle VASST Join Date: Jan 2004 Location: Stockton, UT Posts: 5,648	I'll chime in here and say that anyone who'd buy an uncompressed card prior to NAB 2005 (between now and then) is acting out of impulse more likely than sensibility. You'll see several wonderful solutions at NAB. I'm testing one now....but can't say more. But it is sweet and stunning! __________________ Douglas Spotted Eagle/Spot Author, producer, composer Certified Sony Vegas Trainer http://www.vasst.com

March 8th, 2006, 12:02 PM	#29
Alex Raskin Trustee Join Date: Sep 2003 Posts: 1,435	Uncompressed Component for compositing Dustin, David et al: With Decklink HD + Decklink Multibridge... have you had a chance to compare the quality of the video captured off Sony's Component out vs. MPEG (firewire/tape)? Does the improvement in quality warrant a $2,600 extra hardware cost? Most importantly, have you seen an improvement in green screen keying? (Any chance of screen grabs...)

January 28th, 2005, 09:48 AM	#17
R Geoff Baker Major Player Join Date: Jan 2005 Location: Ottawa, ON Posts: 471	There is of course no chance that the component outputs are 'compressed', as analog outputs can't be -- but the question is has the output video been through the compressor & back out again -- is it a video output of decoded compressed video. The simple answer seems to be no -- the component output from a live signal has not been compressed & decompressed ... however, it has been chroma down sampled so it is NOT pristine, 'uncompressed' in the sense that it is full quality. Is there a gain if the component output is recorded using a higher quality recorder? Yes, in that there is no mpeg compression-decompression cycle and so no mpeg artifacting. But not as good as one could wish, and certainly not at the standard of 10 bit, 4:2:2 chroma. GB

January 29th, 2005, 01:57 AM	#18
David Farland Regular Crew Join Date: Dec 2004 Location: Sydney Posts: 32	Don’t want to have arguments of what exactly what ITU standard or effective bit depth/colour space the live component out is until Sony Japan gets back to me with their engineering specification on the output. Suffice to say capturing the component should remove mpeg artifacts, provide more robust editing/compositing which will ‘make’ the solution for a few people. Is it 4:2:2 or 4:2:0….dunno. Currently I’m looking at lithium-ion battery packs to power the capture system for a couple of hours. Pre-built battery arrays seem to range from $1000~1500. 100watts of battery weighs the same as a 3.5” disk unit (.6kg)probably need 6 plus controller boards for 2 hours shooting. http://www.ocean-server.com/battery_packs.html. Here is one supplier, Jon Crowell who knows his stuff when it comes to powering pc’s with batteries. Thank you, Dave Farland

February 3rd, 2005, 03:00 AM	#19
Thomas Smet Trustee Join Date: Mar 2004 Location: Milwaukee, WI Posts: 1,719	Can the Z1 or FX 1 output from the component jacks a SD signal? If so can it do it while shooting HD or does the camera have to be in DV mode? The equipment costs wouldn't need to be as high then for storage. Many of us will still be doing SD projects for some time yet. You may also be able to get by with a fairly portable capture system. You could use a high end laptop with Liquid Edition 6 pro. The LE 6 pro break out box connects to a USB2 port and captures from component uncompressed video. You would then only need to lug around a laptop, external G-raid, and the small LE6 bob.

February 3rd, 2005, 06:40 PM	#20
David Farland Regular Crew Join Date: Dec 2004 Location: Sydney Posts: 32	Very good idea Thomas but unfortunately you can't down-rez the component output to SD while recording in HDV. Sure you can on play back though. Blackmagic sells it’s Decklink SD ($295) card which can down rez HD to SD but they recommend a HD platform http://www.blackmagic-design.com/site/65support.htm to support it. Not sure the minimum BM spec for a HD to SD capture only system as BM talk about their Decklink SD/ HD host system replaying HD footage in SD which wouldn’t be required here. Thank you, David Farland

February 4th, 2005, 01:39 AM	#21
David Farland Regular Crew Join Date: Dec 2004 Location: Sydney Posts: 32	Little more on the FX1 component out specification... I asked Sony Japan the following question:- What is the “ITU” standard that describes this component video output? Sony replied:- "The ITU standard is IT-R BT.709 and the factory says there is no recommended setting value of Digital Standard". (Sony Japan) I'm waiting on more info...... Thanks you, David Farland

March 16th, 2005, 08:34 AM	#22
Karel Bata Regular Crew Join Date: Oct 2004 Location: London, Antarctica Posts: 199	A very interesting thread here... And a little amusing too. Already we are getting used to the notion of employing a focus-puller on video shoots when the final product is meant for theatrical projection, and now we might even bring back the equivalent of the 'video-assist' playback operator! So I took a look at what equipment playback operators currently use on film shoots. This is the Omega deck (notice the removable hard drives) The Digiclam The Digi Combo and a software version, Cinelog which can be used with proprietary hardware So what you're aiming at is something not too dissimilar to one of these systems, right? But with a much higher throughput of data to allow the recording of component HD video. You could also go a step further and build in some of the features that are on these systems such as mixing images (for critical line-ups) or variable speed playback. Of course not everyone who owns an HDV camera would want one, nor - I think - would many HDV owners who'd have a use for it want it on every shoot. But it opens up the possibly of building a dedicated system (like some 35mm video assist operators already do) which can then be rented out to shoots. In the UK this looks tempting... As to this question of a high shooting ratio eating up disk space: well, again you go back to something like traditional film practices. You record everything, including rehearsals, log the 'selected takes' (the old continuity girl's job (I liked her - let's have her back!)) and then delete everything you don't want, making room for the next set up. Meanwhile - if you choose - you can also record everything using the camera's own tape transport to give you a back-up if you have a catastrophic failure on your hard drive recorder. The director has to think in terms of a limited amount of memory - like a limited amount of film stock. At the end of the day all the hard drives (which are removable) are taken to the editor. Batteries: as long as it is understood that a mains supply is required either at studio / location, or via a genny, this is not an issue. But a proper reccy may be needed at each location by a competent electrician (big hotels for instance will exhibit a voltage drop and spikes when all the ovens go on mid morning). Some kind of mains supply cleaner or buffer (not my strong point) would be needed.

March 16th, 2005, 09:24 AM	#23
Karel Bata Regular Crew Join Date: Oct 2004 Location: London, Antarctica Posts: 199	Just realised (oh silly me!) that of course the natural person to push the record button on this thing would be the sound recordist - so you don't need an extra member of crew after all. (The poor Video Playback Op was always the first to go...)

March 17th, 2005, 05:12 PM	#24
Thomas Smet Trustee Join Date: Mar 2004 Location: Milwaukee, WI Posts: 1,719	Would the chroma on the Z1 really be reduced right away? It seems like it would like many SD cameras but then I was thinking about how the camera would do it based on different output formats. If you shoot HD you are getting 4:2:0 Now if you shoot DV or DVCAM you get 4:1:1 How can the camera switch the entire chroma output of the block based on what format you are using? To me it seems if the chroma was reduced it was only be down to 4:2:2. This would be an easy point for the camera to get to either 4:1:1 or 4:2:0. If the block only did 4:2:0 where would the extra 1 come from for 4:1:1. The same is true if the block outputs only 4:1:1. The camera would have no way of bumping up to a 2 for 4:2:0. I then thought well maybe during SD shooting the 0 turns to one since only 1 field is used. Well this would work for 480p mode but not regular everyday NTSC video. The two fields for 480i video would have to come from the same alternating fields from the HD block or else the fields would be interpolated. This means that unless the DV from the Z1 is only 4:1:0 the block must output 4:2:2. I then thought about well maybe they kill the chroma near the component output. Well this would mean the signal would have to be run two different methods of chroma reduction based on the format. This seems like it would be hard and rather complex in a camera this small. I could be wrong about all of this. Just my boring and rather useless thoughts on the subject.

March 17th, 2005, 05:42 PM	#25
R Geoff Baker Major Player Join Date: Jan 2005 Location: Ottawa, ON Posts: 471	4:1:1 and 4:2:0 are both the same 'amount' of chroma data -- one quarter the luma resolution -- just differently sited. 4:2:0 describes a chroma 'block' that is two pixels wide and two pixels tall; 4:1:1 describes a chroma rectangle that is four pixels wide and one pixel tall. This is a simplified description, but the salient fact is that both are derived quite easily from the same source chips, as they are -- but for a math trick -- the same. IIRC PAL DV is already 4:2:0 instead of 4:1:1 -- this was in recognition of the 'extra' vertical resolution of PAL. I believe the chroma downsampling is done at the imaging block before being sent to the encoder. GB

March 17th, 2005, 09:04 PM	#27
Thomas Smet Trustee Join Date: Mar 2004 Location: Milwaukee, WI Posts: 1,719	So you are saying there is a software code hardwired into the camera that will change the way the chroma is output based on what format you are selecting? It then does this before hitting the encoder block? Wow if that is true SONY put a lot of effort into dumping down the live video from the camera as to not compete with the higher end gear. I know how the two chroma formats work, I just didn't think SONY would go to all that trouble to make the chroma dump thing complex enough to switch based on the format chosen.

March 17th, 2005, 10:13 PM	#28
R Geoff Baker Major Player Join Date: Jan 2005 Location: Ottawa, ON Posts: 471	No, I'm saying that the chroma downsampling is the same for both as far as the imaging block is concerned, and whether the downsampled chroma gets encoded as 4:2:0 or 4:1:1 makes no difference to the imaging block ... Either way the encoder gets a chroma downsampled source, how it chooses to manage that downsampled chroma becomes a codec choice. GB

April 3rd, 2006, 11:20 AM	#30
Alex Raskin Trustee Join Date: Sep 2003 Posts: 1,435	OK, seem slike no-one has implemented this yet. So I decided to bite the bullet and build a uncompressed ingest system. (Thanks to everyone and especially David Farland for inspiration and info!) Results and MPEG vs Uncompressed HD comparison photos are posted on my site: www.PrimeHD.com I'm now looking for a Varicam to check if our system works with it, in practice. If you have a Varicam in NY or Northern NJ area, please let me know (my web site has a contact form...)