Green Frames? That G5 render is not as good as your Intel does in ProRes.

[gary adcock]

Since I was asked this question in another thread, rather than hijack the HDCam offline I will post this info as part of something new.

[gary adcock] “You do know that prores software encoded on a non intel machine does not have the same level of quality as the same file processed in the same way on an intel machine.

“ProRes was designed to be an intermediate codec to keep the postproduction workflow data at 10bit quality, yet at a low enough bandwidth to be usable. It is considered to be a variable bit rate codec, where the amount of compression varies based on frame rate, inter-frame differences and the like. Much like h.264 for iTunes, it operates as a scalar codec, with the ability for full frame playback previews from ½ or ¼ size frame data, lowering the data throughput while maintaining quality”
(from an article I wrote on prores).

So, on a non intel machine, because of ProRes’s ability to handle data in VBR, means that differences between encoding on various CPU’s. ProRes did not even originally run on non intel machines, and it nearly impossible to directly capture to without the intel’s sheer number crunching power. Hence the reason so many post here lately have been lamenting the “green frames” on playback issue.

Those frames are a hiccup in the CPU’s processing that causes the compression skip. On Non intel machines my tests on 4 different G5 config’s showed not one was using anything but the 1/4 rez playback. You can see this for yourself if working on a kona card- open the Kona control panel and look at the frame buffer indicator – if the word ProRes is indicated in red- you are NOT getting full frame playback.

OK here you go. Gary’s rules for ProRes

1) Use it- it is by far the best codec FCP has ever had, it blows DVCPROHD out of the water in post.
it wants a new machine if you are not on intel- it’s about time.

2) ProRes HQ should only used when Captured Via Hardware when creating it from any camera except RED and the PHANTOM. Those are ONLY 2 Tapeless cameras that can actually use the advantages that ProRes HQ offers when working in a tapeless system since they actually record more than 10 bits as data.

3) Software Conversions from previously captured materials or data transfered formats do not need anything more than the Standard Version on ProRes. The reason for this is that camera formats are 8bit, ProRes is 10bit. With the HQ version the CPU is actively interpreting all 256 levels of grey on encode but passing that back out re-interpreted with all 1024 levels on output, that is one HUGE Mathematical Processing task.

4) With the Standard version of ProRes, that data is not re-interpreted on output until the process actually asks the CPU to handle the content in 10bit by adding filters, efx, or color correction. So normal playback of your timeline is unaffected until you do something to it.

5) Every thin raster camera (both HDV & DVCPROHD) will deliver better results when they content is played out via the camera mfg’s hardware- because the video has to be SMPTE compliant, the process using specifically customized decompression tools will ALWAYS beat a software conversion of the same content.

On a suitably powered intel machine I have had no issues with ProRes, I have ingested over 100TB (NOT a typo) in my testing of ProRes and I can gladly say it is the best thing Apple has done for Post Production since buying Key Grip from Macromedia….

FYI
all of these test are not just me making moral judgments I do not trust what my eyes tell me, I trust what the scopes tell me, that kind of hardware is less biased than I can be. So all of the tests were carried out with scopes and analytical tools to calibrate, process and monitor the images.

gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows

Inside look at the IoHD
https://library.creativecow.net/articles/adcock_gary/AJAIOHD.php

[Sean ONeil]

It would be interesting if someone did an AE “difference matte” test comparing the same scene, one captured on Intel and one with PPC.

Sean

[gary adcock]

[Sean ONeil] “It would be interesting if someone did an AE “difference matte” test comparing the same scene, one captured on Intel and one with PPC”

I did on some of the files, but the analysis hardware can do that for me and I get an analytical look at the image degradation without the bias in interpolation.

Let me also say that I am looking at this issue with a more critical eye than necessary.

I can say that I saw much more of an issue rendering ProRes on a G5 vs. Intel than I did looking at the difference between the Standard and HQ versions of the same file as captured, which in the test were repeatably within .5% ( one half of 1 percent) of each other analytically, or about 1/10th the margin of error in the computations.

gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows

Inside look at the IoHD
https://library.creativecow.net/articles/adcock_gary/AJAIOHD.php

[David Roth Weiss]

[gary adcock] “You can see this for yourself if working on a kona card- open the Kona control panel and look at the frame buffer indicator – if the word ProRes is indicated in red- you are NOT getting full frame playback. “

Gary,

Did you test by capturing HDV to ProRes via firewire? Because there’s is nothing similar to what you describe that is indicated on the Kona control panel when dealing with ProRes captured using that method.

I can send you a small file to test if that was not otherwise part of your earlier testing.

David

David Roth Weiss
Director/Editor
David Weiss Productions, Inc.
Los Angeles

POST-PRODUCTION WITHOUT THE USUAL INSANITY ™

A forum host of Creative COW’s Apple Final Cut Pro, Business & Marketing, and Indie Film & Documentary forums.

[Jeremy Garchow]

Thanks, for this info, Gary.

[gary adcock] “Those are ONLY 2 Tapeless cameras that can actually use the advantages that ProRes HQ offers when working in a tapeless system since they actually record more than 10 bits as data. “

Can you throw AVC-Intra in to the mix on that one?

[gary adcock]

[David Roth Weiss] “Did you test by capturing HDV to ProRes via firewire?”

yeah, how else could I test it.

[David Roth Weiss] “Because there’s is nothing similar to what you describe that is indicated on the Kona control panel when dealing with ProRes captured using that method.”

FW does not touch the kona control panel, the red indicator only shows when you playback the content via the kona hardware.

my tests were done using OSX 10.5.4, QT 7.5 FCP v6.0.4.

gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows

Inside look at the IoHD
https://library.creativecow.net/articles/adcock_gary/AJAIOHD.php

[David Roth Weiss]

[gary adcock] “FW does not touch the kona control panel, the red indicator only shows when you playback the content via the kona hardware. “

Yes, I got that. But, on my Kona LH I get no red indicator.

David Roth Weiss
Director/Editor
David Weiss Productions, Inc.
Los Angeles

POST-PRODUCTION WITHOUT THE USUAL INSANITY ™

A forum host of Creative COW’s Apple Final Cut Pro, Business & Marketing, and Indie Film & Documentary forums.

[gary adcock]

[Jeremy Garchow] “Can you throw AVC-Intra in to the mix on that one? “

When these test were started AVC-Intra did not play in FCP.

the difference between AVC-Intra and the other 2 tapeless codecs is that they are actually 12 (Red) and 14 bit ( Phantom) formats whereas AVC-Intra is mpeg compressed at 10bit.

On that note do you think that AVC-Intra on the 1/3 vs 1/2 vs 2/3 is going to show a noticeable difference? Compression levels of this type will really benefit from using Panasonic’s proprietary decompression algorithms, maybe not as much as DVCProHD does (because of scaling).

That being said, I saw no difference in my tests between standard and HQ from Panny’s 10 bit codec other than the file being about 25% smaller for the standard version.- so for me it is all about utilizing
bandwidth efficiently, with standard ProRes being playable on many more machines.

FYI
One of these days I need my camera chart back, I guess really need to walk to your place and pick it up.

ga

[Jeremy Garchow]

[gary adcock] “When these test were started AVC-Intra did not play in FCP. “

RIght, but I am talking about converting a 10-bit in camera format and not an 8-bit format to ProRes or HQ. WOuld it be worth ProResHQ if you need it, similar but different to phantom or red in that’s it’s higher than 8bit natively, but different than all other tapeless formats.

[gary adcock] “On that note do you think that AVC-Intra on the 1/3 vs 1/2 vs 2/3 is going to show a noticeable difference? “

No doubt.

[gary adcock] “FYI
One of these days I need my camera chart back, I guess really need to walk to your place and pick it up. “

I can drop it off dude. You around? Hit em up off list.

Jeremy

[gary adcock]

[Jeremy Garchow] “RIght, but I am talking about converting a 10-bit in camera format and not an 8-bit format to ProRes or HQ. WOuld it be worth ProResHQ if you need it,”

My reason for ProResHQ for the higher bit depth cameras is to allow for optimal control in post since the cameras I mention both require larger amounts of color correction due to the nature of working in a Raw non-managed colorspace. AVC-I only operates in the REC 709 color space, so it by its nature has / needs / cares about the subtly needed for pulling life out of image with a gamma of 1.1

What did you own tests show? Both versions of ProRes are 10bit, so there is infinitesimal amounts of loss when switching to one or the other.

I guess for nearly everyone not doing efx or green screen, that S-ProRez would suffice, its still 10bit, holds up well for multiple generations, and is something on the order of 30% smaller file size than HQ ProRes.

HOWEVER….
The one point I avoided there was anyone (like you) running a computer fast enough to decode AVC-Intra on the fly should be able to handle ProRes HQ without issue. \: }

But that means that for the best handling of ProRes- try the Standard version FIRST- it’s really really good and handling anything you can throw at it, and it will not break the bank or your spirit with loathsomely mysterious “green frames” tossed in for good measure.

Most people here say they want the best but they are not willing to put in the time,effort and a lot of cash to get there.

I say try the “generic” ProRes Standard version and be just as happy with a lot less hassle.

gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows

Inside look at the IoHD
https://library.creativecow.net/articles/adcock_gary/AJAIOHD.php