AVC Intra vs ALL-I

H

Hugh DiMauro

Well-known member
Hello Forum:

I'm hoping to have a Panasonic expert field my inquiry. I used to own the Panasonic HPX-170, HPX-250 and AG HPX-370, all recording AVC-Intra 50 and AVC Intra 100 codecs with an MXF wrapper 10 bit, 422 onto P2 cards. Panasonic refers to this codec as "archival quality." Now I own the Panasonic GH5 and GH5s, recording H.264 ALL-I (intraframe) at 400 Mb/s (UHD), 200 Mb/s at HD, both 10 bit 422. Here is my question:

1) AVC Intra (intraframe) on the P2 cameras is an HD, H.264 codec (MXF wrapper) that shoots 10 bit 422 50 Mb/s and 100 Mb/s.

2) The ALL-I HD internal codec (intraframe) on the Panasonic GH5 is also H.264, (.MOV wrapper) 10 bit 422 at 200 Mb/s.

Question: Even though the internal codec within the GH5 does not call itself "AVC Intra" but still shares the same technical aspects of AVC Intra, could I assume the GH5 HD internal codec at 200 Mb/s outperforms the AVC Intra HD 100 Mb/s in the abovementioned cameras and even the newest Varicam when set to AVC Intra 100?

Thank You.
 
This is probably still the best answer... https://www.dvxuser.com/forum/hdslrs...ity-comparison

No matter what they call it or how good of a codec there is, a small chip camcorder could only provide so much quality. Same on the other end; a professional cinema camera with very dedicated resources to processing and image quality might have an old codec but could look better (or pleasantly different) than a newer stills camera that shoots video with a very new codec.

These are mostly just names assigned to technology, and everything depends on the actual technology and how it's working.

A drone shooting ProRes does not look like an Alexa shooting exactly the same licensed ProRes.
 
NorBro, you mentioned something interesting in your earlier post:

"The idea of grading ProRes was only made famous by ARRI (and later Blackmagic) since no other cameras ever offered it until many years later after those two. Atomos jumped on the opportunity but 99% of the world grades H.264 or H.265 because that's what most cameras have today (and RAW)."

I had no idea 99% of filmmakers grade H.264 and H.265! From what I've read, H.264 and H.265 is strictly a "finishing" codec and does not hold up well to any manipulation and assumed I always needed an external recorder with ProRes to avoid H.264 and H.265 as an acquisistion codec. But you are saying many pros use H.264 and H.265 and are okay with that as an acquisition codec and okay putting it through some light post processing which is what many professionals in the industry now do?
 
99% applies to like everyone in the world using a camera, but at certain levels the percentage is much less e.g. a production being shot with RED cameras which then it's 0% because they are definitely using REDCODE RAW.

But, yeah, a lot of those other cameras have the high-quality H.265 and H.264 options and that's more than enough for many.

And those options might be considered "finishing" codecs yesteryear, but times have changed and that concept doesn't apply the same way it once did. Because when critically thinking about it, if we want to use a specific camera then we take whatever the companies offer us and we grade that (we have no other choice). And computers today are powerful and fast enough to handle most offerings and you can edit and finish with whatever you'd like, especially in a YouTube world.

It's like what's the difference if it looks good and post isn't painful, you know?

___

I used to be pretty obsessed with external recorders and recording ProRes to bypass the H.264, but at some point around 2017/2018 I noticed a new generation of camera quality with the 4K models that started looking really good, much better. They weren't the 5D Mark IIs and what not anymore, but higher-quality chips that had more resolution and better processing and additional flexibility to push the image around. Not drastically but enough.

As far as professionals...if you're strictly speaking about professionals working with/for specific companies and under certain guidelines then they have to use certain tech. Sometimes those finishing codecs might be accepted and sometimes not. Sometimes they would be able to use cameras like the GH5, but usually never. Really depends.

But if any person who makes a living with a camera is a professional...yes, many are more than okay putting H.264/H.265 through some light post processing, especially if the quality is truly indistinguishable from some of the better options and you save a bunch of card space. [At some point, with the ProRes external recording, many of us realized it was a waste of time and space because there was almost no practical difference at all compared to the internal recording.]
 
Hugh DiMauro said:
Hello Forum:

Question: Even though the internal codec within the GH5 does not call itself "AVC Intra" but still shares the same technical aspects of AVC Intra, could I assume the GH5 HD internal codec at 200 Mb/s outperforms the AVC Intra HD 100 Mb/s in the abovementioned cameras and even the newest Varicam when set to AVC Intra 100?
Click to expand...

There are so many variables that can affect the choice of codec. Complexity of scene, motion, the complexity of that motion and the bit depth, 8, 10, 12 bits used, and ultimately the data rates used. Maybe have a look at this video. As a general rule, I find what Kurtenbach Film says and demonstrates in the following video to be broadly applicable across Canon, Panasonic and Sony H.264 based codecs regardless of the profiles and levels used in the cameras. His video covers the major differences between RAW, Long GOP Intra and I-Frame codecs. Along with some pretty detailed examples. His final statements basically sum up my impressions, having used all both Long GOP and I-Frame quite extensively ever since they were first introduced by Sony back in 2013 with the F55 and F5. It's long but sit down with a coffee or beer, and it may throw some light on the subject for you. For me, this video came as a confirmation of my own experiences and conclusions using the various codecs.

Chris Young

 
NorBro and CYVIDEO, thank you. I have the coffee. Watching the video now. My end game here is to just be able to streamline my run-and-gun video assignments in a way to maximize quality while allowing me to save time as a one man band shlepping equipment all over creation on video shoots. You might just be interested on how I've configured my setup!
 
Just watched the video! FABULOUS! Thank you. I never had any interest shooting raw nor V-LOG before this video and still feel the same now. So, in essence, you helped galvanize my workflow to what I've been doing all along. I am content with how the GH5 natural picture profile and ALL-I, 24p, 10 bit, 422, 400Mb/s UHD looks and my editing system can easily handle that along with the Apple ProRes files from my Ninja V and BMPCC4K. I guess I'm in a good place after all. Thank you, gentlemen.
 
H.265 is more decoding intensive than H.264 since it is more compressed for the same quality. I-frame or not, it requires a lot more processing resources to decode in real time for editing making proxy editing a must for modestly priced computers. The H.xxx containers insure streaming compliance over say MXF camera file containers. But the underlying video is still some version of MPEG4. Recompression of H.xxx originals for delivery will typically suffer more degradation than a DI codec like Prores, DNX or Cineform or any of the raw original formats.
Recording in Prores has become a common in camera option on new cameras if one is prepared to deal with the file sizes.
 
Hugh DiMauro said:
Hello Forum:
Question: Even though the internal codec within the GH5 does not call itself "AVC Intra" but still shares the same technical aspects of AVC Intra, could I assume the GH5 HD internal codec at 200 Mb/s outperforms the AVC Intra HD 100 Mb/s in the abovementioned cameras and even the newest Varicam when set to AVC Intra 100?

Thank You.
Click to expand...

It is a good question. Time seems to be very important with codecs. The evolution of encoding efficiency and quality has been pretty quick since the start of the HD era. While the AVC-Intra 100 was strong for its day, I would expect newer implementations to outperform. I am not sure how set in stone the AVC codecs are as they persist in current Panasonic cameras. So I wonder if they have any wiggle room to update them.

One other view is that the GH5 is not from the broadcast division and by many accounts, the different divisions do not communicate as much as one would think. So the GH5 codec is coming more from a consumer background which might be hinderance. NorBro is speaking to general end image quality imho and I think we all can agree that most everything looks very good these days. Since you can't use AVC-Intra in the GH5, it is kind of a moot point anyway. 10bit 4:2:2 with "enough" bitrate is probably more important anyway.
 
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