Noise comparison: 35/4:2:0 vs. 180/4:2:2

[Mark Job]

Originally Posted by Dan Keaton

Dear Friends,

As I understand it, there are three flavors of Sony XDCam:

XDCam HD, 1440 x 1080 4:2:0
XDCam, 1920 x 1080 4:2:2
XDCam EX, 1920 x 1080 4:2:0

.....Dear Dan: I have to tell you that no High School, Community College, or especially ANY University will accept written papers or essays with citations from Wikipedia, because Wikipedia is often presenting erroneous data as factual and accurate.

According to Sony's White Paper data: XDCAM HD is 1440 x 1080 AND 1920 x 1080
**XDCAM = Standard NTSC Definition @ 720 x 480, or 486 and PAL Spec ONLY.
The Nano Flash therefore *must possess a Sony hardware encoder of the XDCAM HD 4:2:2 persuasion. The XDCAM HD spec can ALSO do Standard NTSC Definition. EDIT: XDCAM is 4:2:0 and XDCAM HD is 4:2:2
-------------------------------------------------------------------------------------------------- [/QUOTE]

[Alan Emery]

Hi Dan,

I am out of my league here, but as I understand the principle, the nanoflash pulls the signal from the HD SDI stage and so circumvents the compression by the camera, thus giving the option of compression to the nanoflash. I realize this is a bit of an oversimplification because not all HD SDI signals are the same.

The key to the puzzle would presumably be to compare the HD SDI signals from the XDCAM EX and the XDCAM HD cameras (not the final codecs). If the HD SDI signals are the same, then the request seems to be to have the nanoflash compress the signal from 1920x1080 to 1440x1080.

At that point I am lost because I am not sure why you would do that....???

Alan

[Mark Job]

Hi Dan:
Another reason why I am thinking the Sony hardware encodrer in the Nano/XDR is of the XDCAM HD 4:2:2 verity, is because the XDCAM regular encoder *cannot ALSO do XDCAM EX. Only the more modern XDCAM HD 4:2:2 encoder can do the extra XDCAM EX 4:2:0 codec as well.

[Dan Keaton]

Dear Mark,

For each quote, I referrenced the source, Many of these were from official Sony websites.

I am well aware that Wikipedia has errors.

Sony's labeling is confusing.

In any case, I listed what the nanoFlash can do.

Whether you want to call it Sony XDCam, XDCam HD, or EXCam EX does not really matter.

I have listed the modes that we can do, which includes the formats used by the Sony PDW-330, 350, and 355, and the modes used by Sony XDCam EX (EX1, EX1R, EX3, PMW-320 and PDW-350), and the modes used by the Sony PDW-700 and PDW-F800.

Thus we handle the 1920 x 1080 and 1440 x 1080 as well has 720p 1280 x 720.

Would you like to include a link to the Sony White Paper you reference?

[Dan Keaton]

Dear Alan,

We added the 1440 x 1080 mode, to match the output of the PDW-330, PDW-350, and PDW-355 cameras at the request of a major Hollywood studio.

[Mark Job]

Originally Posted by Dan Keaton

Dear Mark,
Would you like to include a link to the Sony White Paper you reference?

Dear Dan: Yes Dan I would. You can download the white paper from http://pro.sony.com/bbsccms/assets/f...itePaper_F.pdf

[Piotr Wozniacki]

The document confirms what I had been saying many times - that for 50i, 25p the GOP length should be 12, not 15.

[Mark Job]

Originally Posted by Dan Keaton

Dear Mark,

Sony's labeling is confusing.

Yes. I agree it is.

Originally Posted by Dan Keaton

In any case, I listed what the nanoFlash can do.

Yes you did, but I found your post confusing.

Originally Posted by Dan Keaton

you want to call it Sony XDCam, XDCam HD, or EXCam EX does not really matter.

...Yes I think it does, because depending on which one it is, it can neither do HD or XDCAM EX 1440x 1080 codec. (Regular XDCAM can't). XDCAM HD 4:2:2 hardware encoders *implement one pass realtime VBR encoding.

Originally Posted by Dan Keaton

have listed the modes that we can do, which includes the formats used by the Sony PDW-330, 350, and 355, and the modes used by Sony XDCam EX (EX1, EX1R, EX3, PMW-320 and PDW-350), and the modes used by the Sony PDW-700 and PDW-F800.

....You listed the Sony PDW-F800. OK, but that's a well known XDCAM HD 4:2:2 camera, and this is part of what I find confusing.

Originally Posted by Dan Keaton

Thus we handle the 1920 x 1080 and 1440 x 1080 as well has 720p 1280 x 720.

...OK, and you also can do regular SD and HD .MPG, which is also a cool feature.

[Mark Job]

Originally Posted by Piotr Wozniacki

The document confirms what I had been saying many times - that for 50i, 25p the GOP length should be 12, not 15.

Hi Piotr: I wonder if this is yet another reason why Avid Media Composer has difficulty recognizing the Nano/XDR recorded CF card media in AMA mode ? Avid does not *see* the file structure of XDCAM HD files as the same as XDCAM HD files recorded on discs out of the XDCAM HD cameras.

[Piotr Wozniacki]

I have no idea whether this is the reason, Mark, but wanted to thank you for finding out this white paper.

At least now we can start talking facts here, not suppositions, assumption, and wishes...

I hope CD will catch up. Dan is absolutely right when saying that no matter what the names are for standards and codecs, nanoFlash is capable of full raster, 422, at high bit rates (other formats aside). But if this is so (and we all know for the fact it is), this means the nanoFlash codec is in fact the XDCAM HD one - and thus can be fine-tuned and optimized (more optimal GoP lengths, VBR in addition to CBR, etc.).

I really think it's time for some official declaration from CD now.

[Piotr Wozniacki]

Originally Posted by Dan Keaton

The nanoFlash uses XDCam, 1920 x 1080, 4:2:2 at all bit-rates 50 Mbps and higher.

Dear Dan,

I read again through your summary of formats/codecs, and I think where you went wrong in your above statement, is when you correctly quoted the PDW-700/F800 as using "XDCAM HD", but interpreted it as XDCAM instead (I have underlined the key fragments of your own quote):

Originally Posted by Dan Keaton

The Sony PDW-700 and PDW-F800 are "XDCam".

The Sony PDW-700 is titled:

"PDW700 Sony Professional XDCAM®
HD Camcorder"

The Sony PDW-F800 is titled:

"PDWF800 Sony Professional XDCAM®
HD422 Camcorder".

AFAIK, XDCAM was the first, Standard Definition, incarnation of the XDCAM "Optical" technology (using Professional disks). The cameras using it have been the PDW-535p or 510p.

And obviously, as the nanoFlash is capable of the 422 HD at bitrates of up to 280, it clearly is of the "XDCAM HD" flavor (and not XDCAM, as you stated earlier).

Also, It's been mentioned many times before that CD recorders use the same encoding chips as the 700 and 800 cameras do.

So all in all, I think all that the article linked to by Mark says is applicable to the nanoFlash - including the VBR option viability.

[Mark Job]

Originally Posted by Piotr Wozniacki

Dear Dan,

I read again through your summary of formats/codecs, and I think where you went wrong in your above statement, is when you correctly quoted the PDW-700/F800 as using "XDCAM HD", but interpreted it as XDCAM instead (I have underlined the key fragments of your own quote):

...I also think it *must XDCAM HD hardware encoder, because the regular XDCAM hardware encoder **cannot do the XDCAM EX codec @ 1440x1080,"" which is also an HD format of course.

Originally Posted by Piotr Wozniacki

AFAIK, XDCAM was the first, Standard Definition, incarnation of the XDCAM "Optical" technology (using Professional disks). The cameras using it have been the PDW-535p or 510p.

....This statement is correct.

Originally Posted by Piotr Wozniacki

And obviously, as the nanoFlash is capable of the 422 HD at bitrates of up to 280, it clearly is of the "XDCAM HD" flavor (and not XDCAM, as you stated earlier).

....Your deductive reasoning is quite correct.

Originally Posted by Piotr Wozniacki

Also, It's been mentioned many times before that CD recorders use the same encoding chips as the 700 and 800 cameras do.

...Yes. This is what threw me for a loop as well. These are well known XDCAM HD 4:2:2 hardware encoding cameras, so why does Dan list them and seem to be see, this proves it ??

Originally Posted by Piotr Wozniacki

So all in all, I think all that the article linked to by Mark says is applicable to the nanoFlash - including the VBR option viability.

...I thank you Piotr for getting to the heart of the matter here. It doesn't matter about listing a whole bunch of XDCAM cameras, or going into what the Nano Flash does- ***The heart of the matter is does the Nano Flash (and by extrapolation, the XDR) possess an XDCAM HD 4:2:2 Full Raster hardware encoder, and thus the Sony specification calls for the implementation of realtime hybrid V B R encoding. Will CD enable this feature ?***

[Alan Emery]

Hi Piotr,

If I understand correctly, you anticipate that reducing the number of pictures in the GOP will reduce the shimmering you observe because the reference image will be renewed more often. Have you observed this shimmering in the final 1920x1080 product? Is it mostly on shiny objects? I am not sure what to look for.

What problem will the variable bit rate solve?

Many thanks,
Alan

[Piotr Wozniacki]

Dear Alan,

If you read the entire thread, you will find answers to both your questions. The VBR encoding superiority over CBR can also be studied in numerous Internet sources. The 12 frames long GOP has long been the industry standard for 50i/25p/24p.

One thing I'd like to add: While I understand CD is currently very busy with maintaining the current firmware quality and reliability (and hopefully, also with introducing the long promised features like card hot-swapping or SDI-embedded + analog audio mixing), I still hope that once they're done with this (and the "important project" they've chosen never to discuss on this official forum of theirs), they will look into optimizing the code so that the maximum quality is squeezed out of the Sony encoding chips.

Piotr

[Lance Librandi]

Hi Piotr,
During my testing of the NanoFlash I also observed the same shimmering when recording Mpeg Long Gop 1920x1080. The same scene was also recorded in I-Frame and the shimmering was no longer an issue, now I record everything in 100Mbps I-Frame as standard.