View Full Version : uncompressed output of FX/Z1, HVX200 and HD100, no 1080p CCD's on any of the cameras?
Radek Svoboda June 6th, 2005, 01:50 PM http://www.dvxuser.com/articles/HVX200/
This is intersting report. The Panasonic camera will be excellent 24p camera, but there this new information:
>>Uncompressed Output:
All three cameras offer uncompressed high-definition output on the component video outputs. The Sony offers 1080i, the JVC offers 720/60p (which can also be cross-converted to 1080/60i), and the Panasonic offers native 1080/60i and 720/60p<<
What does it means? It means that camera CCDs output 1080i60 and 720p60. 1080p is not the CCDs' native output. If was, uncompressed 1080p output would be available.
Panasonic said they'll introduce 1080p cameras in 2007 or 2008, I think. It just not make any sense for Panasonic to offer true 1080p in 5,000 euro camera, if they don't offer in more expensive cameras. So my guess is they derive 1080p from non 1080p CCD's, just like Sony derives 1080p25 via CF25, from non 1080p CCD chipset.
Please correct me if wrong, but IMHO new Panasonic camera will not offer true 1080p because there are no true 1080p CCD's.
It may be best of three cameras, Z1, HD100, and naturally HVX200, but none of these cameras have true 1080p, not at this price point. Panasonic is likely derive 1080p out of 720p. Well, you can the same in post.
Please correct me if missing something. Or explain me why would Panasonic leave out uncompressed 1080p if chipset was capable of this output.
Altasens has, or was planning have 1/2" chipset that was to be used by Ikegami's 3-chip POV camera. It too had 720p, 1080i output, but not 1080p.
Radek
Radek Svoboda June 6th, 2005, 02:00 PM So basically Sony is 1080i50-60 camera, JVC is 720p24-30 camera with 720p60 chipset; Panasonic is variable frame rate 720p4-60 and 1080i50-60 camera. Panasonic is most versatile, will likely better quality 1080i output than Sony and has 2x fps of JVC, at 720p, but none of the cameras have 1080p CCD chipset, so can't claim true 1080p.
Correct me if wrong, please.
Radek
Steven White June 6th, 2005, 02:48 PM This is totally a guess, but I imagine they don't have the internal processing power/bandwidth to deal with 1080p60.
None of us know the specs of the chipset... It seems unlikely that it's 1920x1080P but we'll find out. They can (and will) certainly claim it's "true 1080P" just as Sony claims 1440x1080i with pixel shifting from 960x1080i is "true 1080i".
The actual truth is that 1080p and 1080i are badly enough defined throughout the industry that they're all right and can get away with sub 1920x1080 square pixel resolutions and chipsets.
-Steve
Radek Svoboda June 6th, 2005, 03:08 PM This is totally a guess, but I imagine they don't have the internal processing power/bandwidth to deal with 1080p60.
The camera offers only 30p max. at 1080p, no 60p. 60p would require 200 Mbps; 1080p30 requires same Mbps as 1080i60 and that in DVCPROHD is 100 Mbps at 1280x1080 pixel resolution.
Uncompressed analog output is before compression, gives good indication of what is coming out CCD chipset ADC; 1080p is definitely not coming out.
Radek
Radek Svoboda June 6th, 2005, 03:14 PM I thought since Panasonic is coming out with true 24 fps 1080p camera, so will Canon. Now I don't know about Canon. It is just as easy do 1080i50 as 1080p24. But manufacturers are saving that for more expensive cameras.
Radek
Barry Green June 7th, 2005, 12:39 AM What does it means? It means that camera CCDs output 1080i60 and 720p60.
No, it means you misunderstood what was said there. The CCDs output progressive and interlaced. You're confusing two items -- you're confusing the analog component output signal with what happens at the CCD level.
The CCDs are progressive-scan. They do output a genuine 1080/24p and 1080/30p signal.
The thing is, the progressive-scan images will be recorded and carried within an interlaced data stream. So DVCPRO-HD will record and output 60i, and the 1080/24p and 1080/30p signal will be carried within that 60i signal. This is exactly how the DVX and XL2 and SPX and SDX all derive and record their progressive-scan images. It's also almost exactly the same way the Sony HDCAM records its progressive-scan -- the F900 CineAlta cannot record true progressive-scan, it can only record interlaced, so it breaks progressive frames into interlaced data for the purposes of recording it (which they then call PsF, for Progressive: segmented frame).
It just not make any sense for Panasonic to offer true 1080p in 5,000 euro camera, if they don't offer in more expensive cameras.
I know what you're trying to say and trying to infer from the article, but let me assure you you're not on the right track. They ARE going to offer it, whether it "makes sense" or not -- and they are almost definitely going to add it to their other cameras too. They've already hinted at a forthcoming VariCam II, and I would strongly suspect that it will offer 1080/24p. And it will do so in the exact same way (carrying progressive frames within an interlaced stream) as the HVX will.
So my guess is they derive 1080p from non 1080p CCD's, just like Sony derives 1080p25 via CF25, from non 1080p CCD chipset.
Nope -- 100% incorrect. The CCDs in the DVX are capable of both progressive and interlaced, and the CCDs in the HVX will be the same way.
Please correct me if wrong, but IMHO new Panasonic camera will not offer true 1080p because there are no true 1080p CCD's.
Consider it corrected -- the HVX will introduce 1080p CCDs.
Panasonic is likely derive 1080p out of 720p. Well, you can the same in post.
Nope -- it's done off the chips, not out of some up-rezzing algorithm.
Please correct me if missing something. Or explain me why would Panasonic leave out uncompressed 1080p if chipset was capable of this output.
Because DVCPRO-HD doesn't record 1080p natively. It supports 1080i, not 1080p. But then again, neither does DV -- DV can't record progressive-scan images, but Canon and Panasonic have made it do so, and do so very well. And it's the exact same technique that they will use in the HVX.
Steven White June 7th, 2005, 08:39 AM Nope -- it's done off the chips, not out of some up-rezzing algorithm.
Are you confirming here that the chips indeed have 1080 lines, or are you using the whole 'chip is analog' argument?
I still have yet to read an argument (from Google, Jan or otherwise) to convince be that the resolution of a CCD is actually analog (otherwise, claiming a "960x1080" CCD or some other configuration is meaningless) - if you have an article that makes this explicitly obvious, please share. Yes, the voltages of the potential wells in the CCDs are analog in the classical sense use of the word (not talking about electron-level quantization)... but that doesn't mean the spatial resolution is.
The chips are progressive chips, but they may also be capable of being read as interlaced chips. Unless the chips have 1080 lines, reading an interlaced signal doesn't make any sense. In-camera conversions may well take a 60p image (required for true 720p60 acquisition), and split each frame into fields in a 1080i image.
If the chips have 1080 lines, then they MUST be sampled at 1080p60 prior to image conversions to be capable of 720p60 output - otherwise, there will be interlace artifacts in the 720p60 signal (the 1080i signal will be equivalent from either 1080i60 acquisition or 1080p60 acquision).
Clarify if I've said anything wrong.
As a side note, these discussions are only meaningful at the 60i/p rates. Any 24p or 30p functionality requires that the chips be sampled progressively at 24 Hz or 30 Hz respectively. Whether the signal is STORED as fields is irrelevant to how it was SAMPLED, and how it can be re-converted to be displayed. I assume we are all comfortable enough with 2:3 and 2:3:3:2 pull-downs to understand that TRUE 24p can be stuffed into a 60i STREAM and still be EXTRACTED as TRUE 24p with the only lossess resulting from the compression algorithm.
-Steve
Radek Svoboda June 7th, 2005, 02:28 PM Barry,
Sorry, but we talking apples and oranges, therefore your arguments don't apply. I would like to hear answer form Jan.
You have CCD chipset, then ADC, then tee. One branch goes to uncompressed analog output, other goes to compression circuits and then signal gets recorded.
It does not any difference if it is recorded nativaly in 24p or with pulldown. Either way can get original stuff before pulldown by removing pulldown.
What is intersting is that uncompressed output is either 720p or 1080i. Why is 1080p missing? It either does not exist at this point or Panasonic decided not to make available, which not make sense. Therefore certainly apperas that 1080p is created form 1080i or 720p, the two modes available before compression.
Radek
Dylan Pank June 8th, 2005, 11:02 AM 1080p is "missing" because there is no analogue compatible stream for it (if you like) in a component video output, just like there is no such thing for SD. In the SD world there is 25fps/50i and there is 30fps/60i. There is no 24p. Within the digital MPEG world there IS 24p (for mpegs 1, 2 and 4), but before it can be shown on a standard Def TV (with the exception of specific progressive scan DVD players and TVs) it must be converted from 24p to 60i.
To do this it inserts a pulldown.
the HVX will do the same thing when shooting 24p and outputting/recording 60i.
Radek has stated that the 24p will be derived from 60i, it's the other way around, as it is in the DVX and the Varicam. 60i (or 60p in the case of the Varicam) is derived from 24p.
In the "50Hz" (old PAL region) version there will most likely only be 25p and 50i, but it will be 25p and not CF25-like.
Thomas Smet June 8th, 2005, 07:52 PM You will always get better quality making interlaced from progressive chips opposed to trying to make progressive from interlaced chips.
What do we know...
the HVX-200 will have native progressive chips. This is because of the 720p mode. This means no matter what those chips are progressive scan. Unless the camera has two seperate chip blocks nothing can change this.
the 720p is a true 60p which means the chips scan at 60 fps.
Based on this it is actually very easy to make a perfect 30i stream from 60p by taking every other line from the 60p and alternating every other frame.
We know based on the natural 720p that the chips are progressive no matter how they are sampled to make 1080.
It seems kind of silly to convert a progressive stream to interlaced and then convert back to progressive again. It is much easier to keep the stream progressive and stick it inside of a 1080i stream either as 30i, 30p, or 24p. This is the best way to keep those three formats inside of the same output stream. All three can work together and fit in well with any type of digital or analog display device. How many people can really view a natural 24p 1080 stream anyways? If the HVX-200 were to have a natural 24p output it would have to be a whole new output method seperate from the standard 1080i output device. This would not only complicate the device but jack the price way up.
720p is easy to deal with because no matter what every 720 format is progressive. 1080i has to deal with two different beasts. 1080 needs to deal with both interlaced and progressive video. Instead of making the 1080 mode on the HVX-200 way too complex for that price point all 1080p is placed inside of the 1080i stream. This way they can use the same ouput device for all 1080 video not to mention make it easier to use with any type of equipment including LCD, CRT, Plasma, 1080i capture cards.
I don't really understand the confusion. This is exactly the same way the DVX-100 works. Are you trying to say that for the past few years we have all been duped by Panasonic and the DVX-100 isn't really 24p?
Radek Svoboda June 10th, 2005, 09:46 AM I don't really understand the confusion. This is exactly the same way the DVX-100 works. Are you trying to say that for the past few years we have all been duped by Panasonic and the DVX-100 isn't really 24p?
No confusion on my part. Are you telling that there is uncompressed analog signal available in DVX written to interlaced stream?
You normally write to interlacad stream after compression, not before.
Just because new camera has 720p off of chipset, and 1080i, does not mean it has 1080p available. Please don't teach me how cameras work.
Radek
Jack Zhang June 14th, 2005, 06:32 PM 1080p is definitely not coming out.
And the war of the formats continues! I say, until a fast enough encoder comes out (maybe a Cell Encoder) and a fast enough DSP for the CCDs, 1080p60 would be the dream of many people (myself included) in their portable HD cams. Loosly compressed H.264 might be the cure to the 1080p60 unacceptance fever, and the migration to a HDCAM SR-like DV sized tape would definitively make all the major companys to work with 1080p60 because of it's higher metal particle density. But CCD DSPs is where everything stops. The war will continue until the world's first native 1080p60 CCD or 3CCD system is created with a lightning fast DSP.
The answer might come in the 2008-2009 year of NAB. Until then, the cannons will keep firing in this war.
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