x265 HEVC Encoder

[Sagittaire]

Originally Posted by Motenai Yoda

I'd not be so enthusiast about Ryzen, as the only public comparison is still the amd charts one, and as bulldozer and its derivates are nothing better than intel's ones.

Also 7700k cost now about 340€ (maybe 320/300€ with the 10/15$ prices cut), sure not 400$, and 1700x is (yep) an esacore, but with castrated avx2 and few/no compiler optimizations.

6900k is the actual not plus ultra for a consumer pc so it's baldly overvalued.

There are here in France exclusive test on "CPC hardware magazine" since one month. The test CPU model is 3.15/3.3/3.5 Ghz 8C/16T sample (will be like R7 1700).

Overall benchmark for x264 HB encodaging 2K, x265 HB encodaging 4K, WPrime, PovRay, Blender, 3DMax 2015/Mental Ray, Coronna Benchmark

i7 6900K: 193.4
R7 3.15/3.3/3.5 Ghz: 168.7
i7 6800K: 152.5
i7 6700K: 137.3
i7 4790K: 127.7
FX-8370: 105.2
i5 6600K: 100.0

Make scaling for R7 1800X at 3.6/3.8/4.0 Ghz by yourself ... ;-)

[Sagittaire]

Originally Posted by NikosD

x264 is a lot different than x265 due to AVX2 optimizations.

Yes, I agree that using x264 RyZen is going to have a party.

But x265 has a lot of AVX2 optimizations and it's not possible for RyZen 7 to catch the performance of an Intel 8C/16T.

Rysen seem to have really good AVX/AVX2 implementation too ... Almost as good as Kaby lake

[NikosD]

I certainly don't believe that.

[nevcairiel]

Originally Posted by Sagittaire

Rysen seem to have really good AVX/AVX2 implementation too ... Almost as good as Kaby lake

Even AMD documentation says that AVX/AVX2 is implemented using 128-bit processing units (and not 256-bit), so they have about half the throughput as Intel - which would have quite a strong impact on x265 performance.

Anyway, we'll see actual believable results in a week or so, not "leaked" results or AMD marketing results.

[birdie]

March the 2nd is really close, it's just four days from now. I guess we can all stop and wait for the official benchmarks. Also, there are rumors that AMD has already shipped a million Ryzen CPUs so we'll have a lot of data to chew on.

[LigH]

I'll be curious too. AMD used to be "notorious" for well optimized die designs vs. "brute force" preferred by intel. And even if RyZen is not as powerful as people may hope for, we still have to thank AMD for pushing intel (and Nvidia?) back to a solid ground, regarding price management ... — Thanks birdie for the link a page ago.

[pingfr]

Anyone could take a quick peek at these settings and tell me if I'm missing a tweak here and there, thanks?

C:\x26x>x265.exe --crf 18 --aq-mode 1 --ctu 64 --qg-size 32 --deblock -1:-1 --me star --bframes 6 --rc-lookahead 60 --ref 5 --b-adapt 2 --tu-intra-depth 4 --tu-inter-depth 4 --merange 92 --weightp --weightb --scenecut 40 --rd 4 --limit-ref 0 --limit-modes --tskip --rect --amp --max-merge 5 --subme 7 --b-intra source.y4m -o out.hevc

Thanks!

Edit: Also what about --cutree ?

[aymanalz]

Originally Posted by pingfr

Anyone could take a quick peek at these settings and tell me if I'm missing a tweak here and there, thanks?

C:\x26x>x265.exe --crf 18 --aq-mode 1 --ctu 64 --qg-size 32 --deblock -1:-1 --me star --bframes 6 --rc-lookahead 60 --ref 5 --b-adapt 2 --tu-intra-depth 4 --tu-inter-depth 4 --merange 92 --weightp --weightb --scenecut 40 --rd 4 --limit-ref 0 --limit-modes --tskip --rect --amp --max-merge 5 --subme 7 --b-intra source.y4m -o out.hevc

Thanks!

Edit: Also what about --cutree ?

merange 92 is insanely high. What is the video resolution?

[divxmaster]

Originally Posted by pingfr

Anyone could take a quick peek at these settings and tell me if I'm missing a tweak here and there, thanks?

C:\x26x>x265.exe --crf 18 --aq-mode 1 --ctu 64 --qg-size 32 --deblock -1:-1 --me star --bframes 6 --rc-lookahead 60 --ref 5 --b-adapt 2 --tu-intra-depth 4 --tu-inter-depth 4 --merange 92 --weightp --weightb --scenecut 40 --rd 4 --limit-ref 0 --limit-modes --tskip --rect --amp --max-merge 5 --subme 7 --b-intra source.y4m -o out.hevc

Thanks!

Edit: Also what about --cutree ?

I would add
--rskip --no-sao --no-open-gop
and I prefer
--psy-rdoq 1.1

Cheers,
Divxmaster

[troica]

Hello guys is this x265 and HM reference model the same?

[Selur]

they both implement the same standard, but x265 has lot of optimizations.
HM = example on how it could be done for academic purposes
x265 = real world implementation which is a lot faster and usable

[WhatZit]

Originally Posted by pingfr

Anyone could take a quick peek at these settings and tell me if I'm missing a tweak here and there, thanks?

I'm constantly amazed why people keep pursing gigantic strings of parameters to try and solve a problem that's already been solved.

--tune grain, along with its built-in rc-grain algorithm, fundamentally changes the encoding decisions x265 makes by weighting towards quality over compression (aka high-frequency retention).

The settings contained in these presets...



...retain more detail the slower you go. So much so that you can easily drop your non-grain CRF's BACK one or two notches at the slower presets.

I suspect that most people who don't understand tunegrain have just left the rest of their options at "veryslow CRF18" when "slow CRF20" would probably produce comparable visual quality, faster encodes and smaller filesizes.

This is my current command line, which replaced something 20+ parameters long:

--profile main10 --tune grain --deblock=-6:-6 --no-strong-intra-smoothing

Note that I haven't included the CRF or preset? That's because preset+CRF is ALL I change to adjust speed/filesize whilst still retaining quality for ANY encode, depending on the source.

Now, I'll admit that tunegrain could still undergo some tweaks for speed, and others have suggested the parameters to do that. Myself, I couldn't be happier about ditching the pursuit of endless quality experiments with this-command-line and that-command-line.

[troica]

Originally Posted by Selur

they both implement the same standard, but x265 has lot of optimizations.
HM = example on how it could be done for academic purposes
x265 = real world implementation which is a lot faster and usable

Are they both programmable using visual studios? My thesis is about wireless video transmission using HEVC with HM, but I dont really know how to start using visual studios

[Selur]

not sure what you understand under 'programmable', but both can be compiled with MSVC and iirc both have an API and can be compiled as libraries.
-> no clue how to best start

[troica]

Thanks. I wanted to do generate a log file using HM model that takes the difference in the SNR, quantization parameter etc per frame, ctu, and slice number. Is there such a thing, or should I code manually to do such thing?

[Boulder]

Originally Posted by WhatZit

Now, I'll admit that tunegrain could still undergo some tweaks for speed, and others have suggested the parameters to do that. Myself, I couldn't be happier about ditching the pursuit of endless quality experiments with this-command-line and that-command-line.

This. What I've done is choose --preset slower --tune grain --CRF 21 as the baseline, then picked some recommended settings to tune performance (--limit-refs 3 --limit-tu 3 --rskip) and some quality-related ones from the bottom two presets (--tu-inter-depth 4 --tu-intra-depth 4 --max-merge 4). Produces 10-30% smaller files than x264 with my preferred settings at CRF 18, and seems to keep detail better.

[pingfr]

Originally Posted by aymanalz

merange 92 is insanely high. What is the video resolution?

1920x1080.

[pingfr]

Originally Posted by divxmaster

I would add
--rskip --no-sao --no-open-gop
and I prefer
--psy-rdoq 1.1

I suppose --rskip stands for the "recursion skip", however both veryslow and placebo presets have the value set at 0. I suppose that means they are kind of --no-rskip?

Also I would assume --no-sao disables SAO setting it to 0, whereas every preset excepted for ultrafast and superfast have the value set to 1, makes me to actually WANT the SAO.

Now can some kind soul explain what is the rdoq-level? why is it set at 2 and how to make sure to keep it set at 2 from the command line args?

Thanks.

[froggy1]

@pingfr

you don't want SAO. It blurs things so if you want to preserve detail as much as possible, disable it and disable strong-intra-smoothing as well

[pingfr]

@froggy1: Noted. Any idea why the "best presets" have it enabled then?