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Andrew Reid

New information regarding H.265 on the Panasonic GH5

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The main question is - Does Premiere Pro handle H.265 with same efficiency as H264?
(guess the second question is FCP...)

really thinking to transcode 4k H.264 to H265, only worrid that my machine brley handles the h264 when editing in ppro//

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7 minutes ago, frosti7 said:

The main question is - Does Premiere Pro handle H.265 with same efficiency as H264?
(guess the second question is FCP...)

really thinking to transcode 4k H.264 to H265, only worrid that my machine brley handles the h264 when editing in ppro//

Premiere CC 2017 handles the NX1 H265 files just fine.

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If H265 is really better than H264 in achieving no less quality for about half the bitrate, if H265 can be used for intra, if most editors are now fully ingesting H265, and if Intel chips are ready for H265 (and I think all of this is true), then why is Panasonic not using H265 for all its frame rates? And why is in fact anyone trying to defend not using H265 and accepting the bogus arguments of the Panasonic spokesperson? Somehow the BBC is suspect, which has no commercial interest, but not Panasonic?

This statement makes no sense: "Since the AVC Ultra up to 30p is 400Mbps, it makes sense to be H.264." The point is it could be 200 Mbps and get the same quality using H265.

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2 hours ago, theSUBVERSIVE said:

Since the AVC Ultra up to 30p is 400Mbps, it makes sense to be H.264.

As for 48p, it doesn't look like it's 10-bit 422, a H.264 400Mbps All-I codec wouldn't be enough for 48p, for AVC Ultra it would be around 640Mbps and even at a lower bitrate codec like Sony's XAVC-I, you would still need 480Mbps. Since there is no mention of 500-700Mbps All-I codec, I doubt that 48p will be All-I 10bit 422.

On the other hand Panasonic could very well provide a 200-240Mbps IPB 10-bit 422 codec for 4K60p if they wanted.

Of course it's enough for H.264 at 400Mbit (4K 48p) - it may be half the bitrate of MJPEG for 60p 4K on the 1D X Mark II, but H.264 is a much more efficient codec so will maintain image quality at half the bitrate.

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10 minutes ago, Andrew Reid said:

Of course it's enough for H.264 at 400Mbit (4K 48p) - it may be half the bitrate of MJPEG for 60p 4K on the 1D X Mark II, but H.264 is a much more efficient codec so will maintain image quality at half the bitrate.

Andrew, can you confirm 48p 4k 10bit has been confirmed by Panasonic? The chart really doesn't point to that 

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Can't really confirm it. The chart is open to interpretation with the yellow shading. The camera is only still in pre-production, nothing is locked down yet.

On second glance at the chart it looks like the DCI 4096 x 2160 at 48p is 150Mbit 8bit 4:2:0 if you follow the row and boxing lines, whilst 24p is 10bit 400Mbit

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Even if it only records C4K at 8bit north of 30p, I believe it can output 60p 10bit via HDMI. 

 

I'm curious however what the specs are of the "6K" h.265 video mode. Nick Driftwood said it can record up to 30m at 30p. The exit indicates it's 10bit and 200Mbps which sounds promising!

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3 hours ago, Tai Klyce said:

Even if it only records C4K at 8bit north of 30p, I believe it can output 60p 10bit via HDMI. 

 

I'm curious however what the specs are of the "6K" h.265 video mode. Nick Driftwood said it can record up to 30m at 30p. The exit indicates it's 10bit and 200Mbps which sounds promising!

But it also says 10-bit 420, so it doesn't look like it's 10-bit 422 for now.

6 hours ago, Andrew Reid said:

Of course it's enough for H.264 at 400Mbit (4K 48p) - it may be half the bitrate of MJPEG for 60p 4K on the 1D X Mark II, but H.264 is a much more efficient codec so will maintain image quality at half the bitrate.

I know it's not MJPEG but I based my arguments on AVC codecs we have. Sony offers XAVC-I 480Mbps for 4K48p and Panasonic offers AVC Ultra 640Mbps for 4K48p, sure it's possible to get it by 400Mbps and still have a good quality, but it doens't look like Panasonic is going to do that. Following the chart and getting 400Mbps All-I 10-bit 422 kind of confirms to me that Panasonic is following similar specs to what they already have in the AVC Ultra, they probably will just change the wrapper.

Sure it's still in pre-production but there is not much open to interpretation about the chart. You just follow the lines and you get 4K48p 150Mbps 8-bit 420, the yellow highlight is simply to say what's coming via FW.

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I think it's important to remember that h264 has many flavors for different applications, and at this point they are all pretty mature, and have been tweaked and tuned and tested for almost a decade now to their maximum potential; some for consumer applications where low bitrate/easy en/de-coding is priority over IQ, and some for prosumers/pros who demand quality and have the hardware/software to work with the higher profiles and bitrates. Look at the difference between stock GH2 and the mature hack settings; both are h264, but the tuned settings are undoubtedly better quality.

h265 is new and mostly the only implementations I know of outside of the NX1 have been video chat, mobile platforms etc where again low bitrate and easy en/de-coding are the priority. The NX1's h265 implementation seems decent for a first go, certainly better than early h264; but the bitrate hacks have shown it can be improved, and (AFAIK) the present hacks are only allowing a higher bitrate, not tuning/altering the encoding itself. So when the camera companies' engineers (and hopefully hackers, if they are able to get deep into the NX1 or another h265 camera) start going to a higher bitrate and tuning/tweaking the encoding implentation itself: I think there could be big gains made.

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This h.265 "same quality for half file size" slogan is just true about ridiculously low bitrates, above 100Mbps you gain nothing over h.264 quality wise. 

Kaby Lake encodes/decodes it with full-hardware acceleration, but we don't know yet how efficient it performs the job compared to doing the same with h.264. and just because hardwares are ready, doesn't mean softwares are also ready to use them to their full potential.  

I think 400Mbps is not enough for 48fps. since its ALL-I, for every frame there is only 1MB room. Its a bit low for a 9 megapixel image. 

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@aldolega @Eric Calabros

I completely agree with Aldo, and you main not gain nothing over H264 quality wise,but you gain smaller files, less SD cards, great speeds with lesser (and cheaper) SD cards. These are not small things, while with faster, more expensive cards, 200Mbps are achievable in NX-land. For a high end consumer camera like the ones NX1 competed back then, to get 2 64GB cards, in the price of one faster one, is already a gain, also a gain in smaller hard drives, etc. 

When I shoot multi camera projects, it is just amazing how much space per project I save when I use 2 NX out of 4-5 camera setups.

160Mbps is very stable and great in NX1, a camera that is a little bit younger than the GH4, the issue is not H265, is the specific codec that Samsung put in the camera, which isn't very advanced by today standards.

H265 is the next generation, it is made by the H264 people, I do not see them creating a codec for the next 10 years, worst than the one that created 10 years ago, that would be counter productive one could say..

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9 hours ago, Eric Calabros said:

Kaby Lake encodes/decodes it with full-hardware acceleration, but we don't know yet how efficient it performs the job compared to doing the same with h.264. and just because hardwares are ready, doesn't mean softwares are also ready to use them to their full potential....

Software support is obviously required and this often lags hardware by years. E.g, Intel's Quick Sync hardware-assisted H264 encoder was introduced with Sandy Bridge in 2011. To my knowledge Premiere Pro only recently started supporting that -- and for Windows only, not Mac. That was roughly a six-year gap.

Skylake's Quick Sync has HEVC/H265 support for 8-bits per color channel but Kaby Lake will be required for HEVC at 10-bits per color channel. Hopefully it won't take Adobe six more years to add support for that.

I think nVidia's NVENC has HEVC hardware support starting with Pascal and AMD's VCE with Polaris, but the software development kits, APIs and drivers must be available and stable for application developers to use. So there is a difference between raw hardware availability (in silicon) vs being able to harness that from the application layer, which can require stable and tested SDK and driver support. 

Traditionally there has been concern over image quality of hardware-assisted encoding, but FCPX has used Quick Sync for for years (single pass only) and it looks OK to me. But I don't think it has H265 hardware support yet.

Lots of people want H265 because the file sizes are smaller, but you don't get something for nothing. H265 requires vastly greater computational complexity which means the CPU burden to encode/decode is much greater. In this paper, VP9 was 2,000x slower to encode than x264, and H265 was 3x slower than VP9 (or 6,000x slower than x264). So it took thousands of times more computation to save at most about 50% in size. This is just a single paper and algorithms and efficiencies are improving but it illustrates the basic principle.

iphome.hhi.de/marpe/.../Comp_LD_HEVC_VP9_X264_SPIE_2014-preprint.pdf

If that computation is done in hardware (IOW you essentially get it for free) then it may be a worthwhile penalty. But if only software encode/decode is used for H265, it may be impractically slow. Also if full and high quality software support at the SDK level is not available, the fancy silicon doesn't help much.

For the iPhone it is affordable for Apple to use H265 for Facetime. They completely control both hardware and software, and quantities of scale mean any design or fabrication cost is amortized over 50 million phones per year. If it costs a little more to add H265 logic to a corner of a SoC (System on a Chip) that already has 3 billion transistors, it's no problem.

For a software developer like Adobe, they must deal with three basic H265 hardware acceleration schemes, NVENC, VCE and Quick Sync, some of which have multiple versions, each having varying capability and features. So maybe that explains the delay on Quick Sync in Premiere Pro.

H265/HEVC has also been hampered for years by disputes over royalties and intellectual property, which is one reason Google is pushing VP9 which has roughly similar capability but is open source and royalty free. However VP9 itself will probably be replaced by the similar but improved royalty-free AV1: http://www.streamingmedia.com/Articles/Editorial/What-Is-.../What-is-AV1-111497.aspx

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4 hours ago, joema said:

Software support is obviously required and this often lags hardware by years. E.g, Intel's Quick Sync hardware-assisted H264 encoder was introduced with Sandy Bridge in 2011. To my knowledge Premiere Pro only recently started supporting that -- and for Windows only, not Mac. That was roughly a six-year gap.

Skylake's Quick Sync has HEVC/H265 support for 8-bits per color channel but Kaby Lake will be required for HEVC at 10-bits per color channel. Hopefully it won't take Adobe six more years to add support for that.

I think nVidia's NVENC has HEVC hardware support starting with Pascal and AMD's VCE with Polaris, but the software development kits, APIs and drivers must be available and stable for application developers to use. So there is a difference between raw hardware availability (in silicon) vs being able to harness that from the application layer, which can require stable and tested SDK and driver support. 

Traditionally there has been concern over image quality of hardware-assisted encoding, but FCPX has used Quick Sync for for years (single pass only) and it looks OK to me. But I don't think it has H265 hardware support yet.

Lots of people want H265 because the file sizes are smaller, but you don't get something for nothing. H265 requires vastly greater computational complexity which means the CPU burden to encode/decode is much greater. In this paper, VP9 was 2,000x slower to encode than x264, and H265 was 3x slower than VP9 (or 6,000x slower than x264). So it took thousands of times more computation to save at most about 50% in size. This is just a single paper and algorithms and efficiencies are improving but it illustrates the basic principle.

iphome.hhi.de/marpe/.../Comp_LD_HEVC_VP9_X264_SPIE_2014-preprint.pdf

If that computation is done in hardware (IOW you essentially get it for free) then it may be a worthwhile penalty. But if only software encode/decode is used for H265, it may be impractically slow. Also if full and high quality software support at the SDK level is not available, the fancy silicon doesn't help much.

For the iPhone it is affordable for Apple to use H265 for Facetime. They completely control both hardware and software, and quantities of scale mean any design or fabrication cost is amortized over 50 million phones per year. If it costs a little more to add H265 logic to a corner of a SoC (System on a Chip) that already has 3 billion transistors, it's no problem.

For a software developer like Adobe, they must deal with three basic H265 hardware acceleration schemes, NVENC, VCE and Quick Sync, some of which have multiple versions, each having varying capability and features. So maybe that explains the delay on Quick Sync in Premiere Pro.

H265/HEVC has also been hampered for years by disputes over royalties and intellectual property, which is one reason Google is pushing VP9 which has roughly similar capability but is open source and royalty free. However VP9 itself will probably be replaced by the similar but improved royalty-free AV1: http://www.streamingmedia.com/Articles/Editorial/What-Is-.../What-is-AV1-111497.aspx

Interesting, I've been looking for someone with enough knowledge of HEVC to ask a few questions, so if you have the time, I would appreciate. But before that, from what I've read, VP9 wasn't really as efficient as HEVC, being closer to AVC than HEVC but I don't know how much it has improved since then.

Does HEVC have All-I encoding or just IPB? If it has All-I, how much less tasking would it be compared to the usual IPB? Is there advantages of having an All-I H.265 encoding?

I fully understand that NLEs and computers haven't caught up with HEVC yet but since Panasonic GH5 is already capable of encoding it, I don't see why it shouldn't have H.265 for 4K as well, even if RIGHT NOW most people wouldn't be able to take fully advantage of that.

Well, simply because some people would and as time passes, more and more people would, H.265 is after all the codec of the future and having a camera like a GH5, that is already making some splashes, using HEVC, that by itself would help the industry move forward faster since it would help creating a demand for that. Otherwise we will be stuck and simply waiting for Manufacturers and Software to start supporting whenever the feel like and since there is not much demand, why would that be a priority for them?

So even if I can't personally take full advantage of HEVC now I would like Panasonic to think forward and implement it, if Photo 6K already uses it and if Anamorphic Hi-Res will also use it, I can't see why they couldn't be able to implement it for 4K or even create a 5K video mode. 6:9 5K is 4800px and DCI would be 5120px - which is why this is much more like Photo 5K than Photo 6K, what an unnecessary marketing BS.

Anyway, I'm all for pushing technology forward. C'mon Panasonic, just give people the option to record in H.265 10-bit 422 - since Photo 6K seems to be 10-bit 420 for now.

 

 

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13 hours ago, theSUBVERSIVE said:

...Does HEVC have All-I encoding or just IPB? If it has All-I, how much less tasking would it be compared to the usual IPB? Is there advantages of having an All-I H.265 encoding?...since Panasonic GH5 is already capable of encoding it, I don't see why it shouldn't have H.265 for 4K as well, even if RIGHT NOW most people wouldn't be able to take fully advantage of that...H.265 is after all the codec of the future....a GH5...using HEVC...would help the industry move forward faster...

I'm not an expert in this area, so some of this could be wrong. Panasonic says the GH5 uses HEVC/H265 for 6k stills which would imply it's theoretically usable for All-I (intraframe) video compression. However there could be performance factors (even with hardware assist) that preclude this.

H264 is sometimes described as being usable for All-I, but I don't understand how that is very different from JPG compression of a still. If confined to a single frame or still image, there are major limitations to improving compression at the higher bit rates and file sizes typical of quality photos and video. It's true that newer intraframe algorithms like JPG 2000 can obtain better image quality at low bit rates, but at higher bit rates and and larger file sizes there is less difference. So it seems there's no magic algorithm that can vastly improve compression of a single frame at those bit rates. It may be that Panasonic is using H265 for 6k stills because there's some modest compression improvement over JPG and they've already got the hardware logic on the camera to handle the compute-intensive H265 algorithm. There are more compression gains available with interframe or GOP compression, which is how H264, H265, etc. are generally used. 

Re whether the GH5 supports H265 for 4k video, it may eventually do that, but these things are not easy. There are many factors in video encoding, compression and image quality. It's not like flipping a mode bit to enable it, with no more work required. As can be seen in the Tom's Hardware article from 2011, merely assessing the various parameters and image quality factors of different hardware-accelerated video encoding methods is complex: http://www.tomshardware.com/reviews/video-transcoding-amd-app-nvidia-cuda-intel-quicksync,2839.html

It's not Panasonic's responsibility to expend a lot of resources on a fringe feature when they are trying to launch a new camera and need to prioritize commonly-needed features, all of which require design and testing. It is unclear if H265 will be the codec of the future. It has been encumbered with various legal conflicts about licensing and royalties, which is why the evaluation version of Premiere CC does not have H265 support. Likewise I don't think the free version of Resolve has it. It costs you $1000 if you want to edit H265 content with Resolve. No matter what Panasonic does with the GH5, as long as those royalty and licensing issues exist there will be a major impediment to the widespread adoption of H265. It may be that AV1 will be the codec of the future. Supposedly Youtube will be converting to AV1 as soon as possible: https://en.wikipedia.org/wiki/AOMedia_Video_1

 

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I don't see why 6K Photo would have to be intraframe. The GH4's 4K Photo is IPB.

I would prefer AV1 to take the lead, it is supposedly more advanced/efficient, and it seems restrictions in NLE's like mentioned above would end, as it is free.

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Panasonic is promoting it's 400Mbps=50MB/s All-I H.264 firmware update for the GH5 for some time in "summer". Maybe later. Who knows.

I just looked up what ProRes would have as a bitrate here.
After all ProRes was what people asked for. DNxHD would have been fine too if Panasonic didn't want to pay license fees to Apple.
Prores 422HQ (10Bit 4:2:2) for an UHD image at 25fps would be 734 Mbit/s=330 GB/h=92MB/s.

So my existing, external 10bit Recordings of the current GH4, done with an Atomos Ninja Flame are still at twice the bitrate compared to what Panasonic is promoting for the GH5 maybe at some point in summer?
Remember that H.264 in All-I mode is terribly inefficient because it doesn't use any P or B frames. These are what allows the usual, high H.264 compression ratios.

The existing Sandisk Extreme Pro UHS-2 SD-cards I already use for FullHD raw-recording (1:3 lossless compression, 55MB/s) on both my Blackmagic Pocket Cinema Cameras offer up to 260MB/s write speed. (That's the maximum but shurely the minimum will not be below 100 here.)
Even the old Sandisk Extreme Pro UHS-1 cards had 90MB/s.
And Panasonic seriously claims that it can't go faster then 50MB/s due to the SD cards being too slow?

While having 2 SD card slots that can operate in parallel?

400Mbps is just slightly better then Prores 422LT in terms of bitrate (360Mbps). It's seriously lower then ProRes 422 (489Mbps) and can't compare to the regular Prores 422HQ (not to mention Prores 4444 and 4444XQ as these are rarely used)

Of cause H.264 (Hi422P Intra profile) is a very different compression then ProRes but none of them perform any obvious miracles.

 

 

PS;

Obviously there is no or hardly any hardware acceleration for H.264 Hi422P Intra (10bit 4:2:2) as opposed to the usual 4:2:0 8bit.

(Thread regarding missing 10bit support in NVidia drivers although the hardware supports it.)

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