Pro Res: Did I Miss Something?

[Tim Wilson]

I’m the sort-of author, which is to say, the articles were composed entirely by copying and pasting threads from the dozen+ forums where ProRes conversations were happening.

That said, the things you’re asking about are among the very few I know about myself. 🙂

[Rapscallion] “so when he says that PRORES is actually higher data rate, and therefore indisputably the best codec with the most headroom I’d have to say, “huh?”.”

That’s the exact opposite of the data I gathered. 🙂

Although out of the whole article, this was one of the parts I feel I actually know something about, and wasn’t just copy-pasting.

The comparison of ProRes and uncompressed is to SD, not HD. That’s a comparison that Apple makes, as well as the one that Avid has been using for several years with their DNxHD, which ProRes is clearly modeled on. And indeed, 8-bit uncompressed NTSC SD is around 200 megaBITS/sec., that is, 200 megaBITS.

Which is why the ProRes data rate of 220 megaBITS for 1080i/60 is indeed jaw-dropping.

The other megaBIT numbers I cited were for:
HDCAM = 140 megaBITS
DVCPRO HD = 100 megaBITS

My point there is that calling ProRes 145 “lightweight” ONLY makes sense in comparison to 1:1 HD. It’s heavier than HDCAM and DVCPRO HD, much MUCH heavier than HDV.

I also point out that, because of the strains of compressing ProRes in real time, ProRes is simply a no go as a capture codec for the vast majority of FCP customers — even for G4 FCP-ers who are capturing 10-bit uncompressed HD just fine. That’s because 1:1 HD isn’t processor-intensive. It’s drive-intensive, both for space and speed. But if you have the drives for it, uncompressed HD editing has been working fine for a long time now.

Part 2 of the article focuses on HDV, which has some special issues – ProRes offers some advantages even though it’s 5-ish times heavier than HDV.

I know that’s not your workflow, but the point is that I say many, many times that ProRes offers DISadvantages of space and performance, maybe even dealbreaking performance as a capture format.

The primary advantages are for 1:1 HD production, and for cleanliness of renders in HDCAM, DVCPRO HD, HDV, and others that were designed as capture formats, not production formats.

All of this is why I’d never call ProRes indisputably the best codec. The primary observation of the two articles is that too many people are jumping on ProRes because it’s new and sounds cool, without looking at the best ways to use it…if indeed its worth using for them at all.

I think, used properly, that it’s more useful than not for most people. I was also straight up with some criticisms, notably, that lack of 4:4:4 and RGB makes it useless for film or graphics work, among others.

That’s one reason I don’t, and doubt Apple would, call it “indisputably the best codec.” Even if Apple did, they’d get some collegial pushback from Avid, who shipped the same technology (same DCT compression, same data rates, even the same marketing language)years earlier.

And yes, ProRes 220 at megaBITS per second is very, very compressed compared to uncompressed HD. 🙂

I hope this helps!

Best,
Tim

[Tim Wilson]

Part 1 is an overview of what ProRes IS, what ProRes is NOT (10-bit, lossless, RGB, cross-platform, etc.), performance, use, challenges, real-world system use, and more. You can find it here.

Part 2 starts with follow-up Q&A from part 1, then dives into HDV, Color, 24P, and every combination of these. It also has even more on real-world systems using ProRes. You can find that one here.

While I’m at it, I’ll remind folks that we have a shiny new tutorial and article index that you should really check out. It makes finding your way through our nearly 1000 articles a breeze. You can click on the “Tutorials & Articles” link in the header above, or just click here.

Thanks,
Tim

[Oliver Peters]

I’ve done side-by-side comparisons of Avid’s DNxHD at 145Mbps and FCP’s ProRes422 (normal at 145Mbps) against each other and against uncompressed 8-bit 1080i (the source clip). I used a Difference function to blend the clips – both in their respective NLEs and using exported frames in Photoshop. Both codecs are essentially equivalent and show very minor artifacts due to compression. They are more than adequate for mastering broadcast content.

Sincerely,
Oliver

Oliver Peters Post Production Services, LLC
Orlando, FL
http://www.oliverpeters.com

[Sean Oneil]

[Tim Wilson] “The other megaBIT numbers I cited were for:
HDCAM = 140 megaBITS
DVCPRO HD = 100 megaBITS

My point there is that calling ProRes 145 “lightweight” ONLY makes sense in comparison to 1:1 HD. It’s heavier than HDCAM and DVCPRO HD, much MUCH heavier than HDV.”

It is assumed you are comparing it to 1:1 HD. Comparing ProRes to those other codecs you listed is like comparing apples to oranges. They are very lossy camera codecs and they can’t withstand multiple generations of re-compression. The compression is meant to take place one time only – within the camera itself. This why mastering to regular HDCam or DVCProHD is vastly inferior to making masters with D5 or HDCamSR. People shouldn’t render to those formats, and they should never be used as an intermediate codec (like when sending Quicktime files to a graphic artist). With lossy camera codecs, you are supposed to capture and edit them natively (i.e. over firewire), or you capture, edit, and render to a codec which falls into a completely different category.

That category is a lossless or near-lossless codecs. Uncompressed, ProRes, Sheer, DNxHD, Cineform, JPEG2000, Animation, M-JPEG, P-JPEG, etc. These formats should not be compared to DVCProHD, HDV, and HDcam. Apples and oranges.

So with that in mind, comparing apples to apples, ProRes is indeed a lightweight codec. Especially when you conder the fact that prior to ProRes, the only lossless/near-lossless option in Final Cut sanctioned by Apple was Uncompressed. Which of course is many times larger.

[Uli Plank]

I’m getting fantastic results when capturing to ProRes live from the HDMI of a Canon HV-20

[Tom Wolsky]

How are you doing this Uli? Into a MacPro with a second drive? Or something else?

All the best,

Tom

Author: “Final Cut Pro 5 Editing Essentials” and “Final Cut Express 2 Editing Workshop” Class on Demand “Complete Training for FCP5” and “Final Cut Express Made Easy” DVDs

[Chuck Spaulding]

Making the comparison between the data rates of ProRes [HD] and uncompressed SD is just BS marketing hype that has caused way too much confusion.

Which codec you choose depends on what you hope to accomplish with it.

If, for example you wanted to film out then obviously uncompressed is the way to go. But as you pointed out the data rates are around 192 MEGABYTES per second/11GB’s per minute. For many the cost associated with that amount of data is too high.

SheerVideo, which is a lossless codec providing about 2 to 3:1 compression including an optical [embedded] alpha channel, supports RGB and 4:4:4, and is platform and application agnostic. versus uncompressed, this is much more cost effective work flow if you want to master to film or digital cinema.

If your mastering for broadcast there’s Cineform and ProRes, both are lossy offering approximately 5 to 10:1 compression. However, Cineform works on both Mac’s and PC’s, not only is ProRes Apple only its FCP only, also, neither supports alpha channels. The lack of an embedded alpha channel means that compositing requires two streams of data for each overlay instead of just one, exacerbating the already painful disk thrashing problems associated with such large data rates. So although the data rates of the SheerVideo codec are higher it is still probably a better choice if you are doing much compositing.

As the battle for NLE supremacy continues there is no single or right answer. I think the best we can hope for at the moment is to not get locked into a work flow that we can’t easily change.

If you can’t [or don’t want to] afford working with uncompressed HD and you are a single artisan always working on the same system with direct attached storage then ProRes might be the right solution for you.

But if the projects you work on are spread across multiple artisans on different systems with various applications then the ProRes work flow is probably NOT the right way to go and you should test both the SheerVideo and Cineform codecs.

I’m sure there will be more debate regarding work flow as people experiment with codec other than DVCProHD. All of this may be confussing but at least we are beginning to have some choice.

[Uli Plank]

Yes, into a MacPro with three extra drives RAIDed (we are using them uncompressed too) and Blackmagic’s Infinty. Works like a charm, we are using it for chroma-keying.

Who would have imagined this only two years ago?

Regards,

Uli

Director of the Institute of Media Research (IMF) at Braunschweig University of Arts