Jan Crittenden livingston
Forum Replies Created
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This is the Varizoom controller. We put that up on the advice of Varizoom, and they are now promising delivery at the end of December.
Best,
Jan
Jan Crittenden Livingston
Product Manager, DVCPRO, DVCPRO50, AG-DVX100
Panasonic Broadcast & TV Systems -
[toke lahti] “Well, this wasn’t so friendly. I’ve said many times that I know ccd’s are analog and it wouldn’t make any difference regarding the spatial offset if we were talking about “digital” cmos chips.
Hi Toke, Sorry, you are right, it wasn’t friendly, but I have to say that your wording of things are not so friendly either. There is a tone that feels like somehow we are trying to pull a fast one, that somehow the spatial offset is a bad thing. Even though I said that it is hard to explain without pictures, I have tried. And because you couldn’t understand it you say that the reason you didn’t understand it is because I didn’t explain it very well. I have said that it was not scaling as the information that the red and blue chips see is information that the green one can not see. It is an additive process, you come back and say it is scaling. No I haven’t found this discussion very friendly at all. So I guess I snapped. Sorry.
The fact is, Toke, that because they are analog, it would make a difference if we were talking about CMOS chips as they work very differently.
>Constructing the final YCbCr-image from offsetted rgb-chips is anyway done in after ad-converter, isn’t it?
No it is not.
>It would have been nicer if you would have pointed out those things from my explanation of spatial offset that you think are wrong.
I have tried, but you just turn around and say I am wrong.
>You are not giving any arguments or explanation to support your statement.
It isn’t an argument, I have tried to explain. It is an additive process. I will save any more words for the blog.
Best,
Jan
Jan Crittenden Livingston
Product Manager, DVCPRO, DVCPRO50, AG-DVX100
Panasonic Broadcast & TV Systems -
[toke lahti] “Am I right or missing something, anyone?
Is this conversation boring or does not give any new or additional knowledge about camera technology?”Actually you are missing something. An understanding of 1. the fact that the CCD is an analog device. 2. how spatial offset works.
You will have to wait and see it on Tosh’s blog, because I cannot explain it here well enough for you to know that neither of your look-ups degfine what is going on in spatial offset.
Later,
Jan
Jan Crittenden Livingston
Product Manager, DVCPRO, DVCPRO50, AG-DVX100
Panasonic Broadcast & TV Systems -
Michael,
A 1/3″ 1080 X1920 cip would have no low light capability and no dynamic range. In geneal it would be a bad idea at best. It is a progressive chip set, the DSP captures the signal as a 1080P/60 signal. Then based on how you have the camera set up to record, it wil down convert or cross convert to that format.
As I said before it is a progressive chip set.
Thanks,
Jan
Jan Crittenden Livingston
Product Manager, DVCPRO, DVCPRO50, AG-DVX100
Panasonic Broadcast & TV Systems -
[Michael Brennan] “>.
I understand that the TV industry have used the progressive word but in light of the inappropriate use of the word the Sony ad men are not incorrect, as all ccds are progressive at the face.”
Well according to the engineers that I know, some chips cannot take the full picture as it does not have the ability to look at the entire picture, only half of the array can light up. The words are used to describe what is happening and what can come off of the chip set. If it cannot produce that progressive capture at the output, it should not be marketed as progressive. Otherwise then all chips could be marketed as progressive and the poor customer would be left in a confusing mess. Which one really is progressive? No the terminology should reflect what the chip set is able to deliver.
[Michael Brennan] “>.>Progressive clocking defines the description. Yes we need to use a phrase that desribes the above “progressive clocking chip” would exclude Z1s?”
No there are interlace chips and there are progressive ones.
[Michael Brennan] “>.To be clear, you are saying the ccd on the 200 can output true 1920×1080 60p ie where all 1080 lines are clocked from the ccd well at a rate of 60 frames per sec?”
The signal that is captured from the CCD is a 1080P signal. The CCD is an analog device. There is not a line for line readout in any CCD camera. The CCDs on the HVX200 are not 1080 X 1920, the performance in low light would be unacceptavble. However the output is captured at 1920X1080 and then is converted to the format that is needed, like 1080i or 720P or SD. The 1080P signal only gets recorded in the 2 1080P progressive formats of 24P and 30P and these are segmented frames in a respective pulldown to 1080i. All of this happens before compression and subsampling to bring the signal to DVCPRO HD.
[Michael Brennan] “>.To be clear I am saying that since all ccds are inherently progressive. ie Light hits all the pixels and all pixels are dumped to the well in an instant we need to refine the term.”
The problem is that there are interlace chips and progressive ones and you will have a very difficult time convincing the engineers otherwise. And frankly the convention of saying that the chip is progressive, has in the past and should for the future, defines a CCD that is able to capture and output a full progressive picture. An interlace CCD is one that cannot.
Best,
Jan
Jan Crittenden Livingston
Product Manager, DVCPRO, DVCPRO50, AG-DVX100
Panasonic Broadcast & TV Systems -
[toke lahti] ”
You are telling why it is done, not how..”Toke, the how is with a spatial offset. The Red and Blue chips see information that the green cannot see, and thus when the signals are combined their sum of information is greater. Maybe this will be one of those posts for the Tosh board cause I need pictures to fully explain this. But you can add to the resolution significantly by doing offest. We pioneered the offset back in 1987 with the introduction of our WV-F300 camera and it has been consistantly improved ever since.
[toke lahti] “Scaling means altering pictures resolution.
Eg. when you have 2 ccd’s with 1280×720 resolution and v&h spatial offset, they will create a picture with resolution of 2560×1440. Then pixels are interpolated so that missing subpixels are filled and then picture is scaled down to final resolution.
How can you say that the last action is not done?”Scaling is taking a signal and telling a 960 X 1280 to become 1920 X 2560 with no additional information. It interpolates information to do so. This is not what happens at all, nothing is made up, it is taking information that is there and using it. That is why I am saying that it is not scaling. The camera starts with a 1080P resolution and from there it is scaled down to the other formats and that is the only scaling the camera does.
[toke lahti] “[Jan Crittenden Livingston] “But then you do nothave to be disappointed because it does use horizontal and vertical spatial offset.”
Ok, thank you for leaking this information. Japanese advertising was misleading by saying that it has 1080p-chips.”Unfortunately the only way that you were able to read it was that AltaVista translation and there isn’t a good translation for Japanese into English, the nuance of the Japanese Kanji is subtle. What it said was that the images are captured at 1080P and it works into the various formats from there. BTW, I did leak information on the H & V Spatial Offset, I have stated this before somewhere.
[toke lahti] “I hope the initial capture can also be 1080p24/25/30, since the motion blur of combined 1080p60 frames cannot match the film cadence. You also get more light into the chips with longer exposure time and that means less noise from the chips.”
Well of course if the camera is at 24P capture the motion blur will match that of a 24P capture.
Best,
Jan
Jan Crittenden Livingston
Product Manager, DVCPRO, DVCPRO50, AG-DVX100
Panasonic Broadcast & TV Systems -
Hi,
>Definition of progressive has been made very unclear by marketing of interlace cameras that have processing of the interlace image to create a progressive frame.
You are correct, but frankly it isn’t Panasonic that has marketed that confusion.
>Someone correct me if I’m wrong but as I see it All ccds are progressive at the ccd “face”
No not all CCDs are progressive at the face. Some are interlace, like those on the Z1 camera are interlace. Some chips do not have the ability to light up the entire surface,and clock the output at a progressive rate. Some do. Some can only “take” a picture of half the info. Interlace chips can only do interlace and interpolate to progressive. A progressive chip is more expensive and can take in the entire picture and clock it out at 60 frames.
>A “true” 25p or 30p frame comprises all of the vertical lines from a single exposure/readout of the ccd. Ditto 720 60p. The HDC 1500, Genesis and D20 are cameras that do “true” 1080 60p. (as I understand it)
Actually we can add to that list of cameras with real progresssive imagers starting with the DVX100 series of cameras, in its progressive modes, the SDX900,the SPX800, and the VariCam.
>Sony are calling their new HDCAM XD a progressive camcorder. But the progressive picture is made after the interlace processing!
Well then this is the source of confusion. Calling a camera progressive when it starts as an interlace picture is confusing. And Canon is calling their HDV camera a 24F camera 24F because they know the difference and are being truthful about the engineering. Progressive capture is a marketing hot button, it really means something and to use it on a product that isn’t really, seems like a deceptive practice. When Panasonic uses it, it is what were are doing.
>How will Panasonic use the the p word in relation to the 200?
The camera starts with a progressive chip, a 1080/60P chip. In its 24P or 30P modes, or its variable frame modes, it will change to that time base for capture, but it starts as a progressive chip capture and then makes the conversion, cross conversion or down conversion from there. It is a true progressive chip set and will make progressive pictures, not marketing, but rather, engineering.
Hope this helps,
Jan
Jan Crittenden Livingston
Product Manager, DVCPRO, DVCPRO50, AG-DVX100
Panasonic Broadcast & TV Systems -
Toke:This is where you go wrong. Spatial offset uses fundamentally scaling.
I have a feeling this is another one of those discussions that we will never come to agree as frankly it is not scaling. It is using information that is there and using all of it without making the pixels so small that it suffers in low light or has no dynamic range.
>If you would like to get a rgb-picture as an end result, like with digital cinema cameras (viper/hdcam-sr),
And we would be using a much larger chip set and it would be a completely different camera then, wouldn’t it? In working with the camera we are bringing to the market, one has to engineer to get the best out of the parameters given, 1/3″ chip set, HD capable lens and prism, DVCPRO HD recording, and under $10,000. Big diff from a viper or HDCAM SR or VariCam for that matter.
>And again there’s also no benefit for spatial offset with full resolution chips, because you already have full rez rgb-components, you can’t use more resolution to the YCbCr-components. Because 2/3″ ccd’s are usually full rez chips they don’t use spatiall offset.
Actually in Standard Def 2/3″ cameras it is used, which is why specs for them offer higher res off the camera head than what can be recorded as well.
>Then again 1/3″ chips are so small that for them it is better to use non-full rez ccd’s to get larger area per pixel in the chip so the chip remains more sensitive. And that’s why I’m a bit dissapointed if hvx200 does not use vertical pixel shifting.
But then you do nothave to be disappointed because it does use horizontal and vertical spatial offset.
>Only logical explanation that I can come up on why no vert pixel shift is that it would be more difficult to use with interlaced picture. So interlacing, the great ghost of the analog age, still haunts us…
Since the initial capture from the chip set is a 1080p/60 capture and it downconverts or crossconverts from there, there is not the limitation that you suggest here.
>I think that as long as we are recoring in YCbCr-format, we could always benefit from spatial offset and it would be good idea to Panny to build next varicam with vert&horz pixel shifting 1280×720 chips to produce great 1080p-picture.
We already have a 1080i camera, this is the HDX400.
Best,
Jan
Jan Crittenden Livingston
Product Manager, DVCPRO, DVCPRO50, AG-DVX100
Panasonic Broadcast & TV Systems -
[toke lahti] “Jan, could you enlighten me, why would full res ccd cam (like 2/3″ hdcam) use offset?”
Actually Toke that particular camera does not. Note that I said most, and the 2/3 HD cameras are different, but many of the SD cameras do and probably most of the 1/3″ cameras do.
[toke lahti] “Isn’t it better that you get all color primary subsamples registered at the same spot, both in the ccd block and eg. in the hd-sdi feed?”
See this is where you keep thinking that the signal coming from the CCD is a dgitial signal. It isn’t. It is light transformed to energy, which eventually is transformed to digital after the Black Shading and White Shading circuitry.
[toke lahti] “Why would you displace these subpixels when there is no scaling? “
Because this is not how it works. A spatial offset takes the red and blue chips and covers the non-photosensitive areas of the green chip. This allows a chip set to produce more resolution than what a single chip could do all on its own. These signals make an additive gain to the overall performance of the camera.
An example would be to look at the XL-1 camera. It worked with a CCD assembly that had spatial offset. There are 270,000 pixels in that chip, yet it had better resolution than the competive cameras that had 310,000. How did they do that? With spatial offset. It is not scaling, it is not cheating, it is engineering. It is taking advantage of the techology and the fact that it is an analog signal, it is not a pixel for pixel match up on the recording, it is an analog signal.
Hope that helps,
Jan
Jan Crittenden Livingston
Product Manager, DVCPRO, DVCPRO50, AG-DVX100
Panasonic Broadcast & TV Systems -
Hi,
I am going to direct this back to Paul. I have been over to the City website, and I find nothing that confirms that they will be supporting DVCPRO HD. Do you have a specific link?
Best,
jan
Jan Crittenden Livingston
Product Manager, DVCPRO, DVCPRO50, AG-DVX100
Panasonic Broadcast & TV Systems