What settings do you recommend for SVT-AV1

[ShortKatz]

I only have experiences encoding my movie collection to HEVC. Now I want to start and get a bit more experiences with AV1. I use HandBrake to encode which uses SVT-AV1 (v.1.7.0). After a bit of experimenting I think preset 5 or 4 would be good for movie archiving. 4 takes around double as long as 5. I was wondering, is 4 that much better then 5 to invest the longer encoding time? What preset do you use?

For HEVC I put together a set of parameters to pass to the encoder to improve quality, size and speed to my needs. For AV1 and would need to do this all again. Or is this not needed for AV1? A quick search in the internet gave me some parameters that are often used:

enable-overlays=1:scd=1:enable-tf=0

.
What do you think, is this useful? This flags do increase file size a little bit. Or what do you recommend?

[charliebaby]

hi I'm in the same situation as you, personally I do preset 4 at 5000kb/S it's magnificent and preset 4 is much better than 5 but 5 is not bad too it's up to you to see what you want is strange is that my 16 cores are only used at 30% I have to find a way to ensure that more CPU is used like at 80% like that the encoding time would be shorter

[benwaggoner]

Originally Posted by charliebaby

hi I'm in the same situation as you, personally I do preset 4 at 5000kb/S it's magnificent and preset 4 is much better than 5 but 5 is not bad too it's up to you to see what you want is strange is that my 16 cores are only used at 30% I have to find a way to ensure that more CPU is used like at 80% like that the encoding time would be shorter

Don't assume that using more cores will always improve quality, as a lot of threading techniques can sacrifice some quality. Bigger frames certainly can increase core utilization, but lower resolutions can struggle to find enough to parallelize.

[ShortKatz]

Originally Posted by charliebaby

hi I'm in the same situation as you, personally I do preset 4 at 5000kb/S it's magnificent and preset 4 is much better than 5 but 5 is not bad too it's up to you to see what you want is strange is that my 16 cores are only used at 30% I have to find a way to ensure that more CPU is used like at 80% like that the encoding time would be shorter

Thanks for your recommendation , I will try 4 at 5000kb/s and see. There I found another suggestion of using 4: https://forum.jellyfin.org/t-encodin...&mode=threaded

I also found this, and there seems just a little difference between 4 and 5: https://ottverse.com/analysis-of-svt...nd-crf-values/

The difference between 4 and 5 according to this table are "Filter intra", "Difference-weighted prediction", "Distance-weighted prediction" and "Restoration Filter - SG Filter": https://gitlab.com/AOMediaCodec/SVT-...hat-presets-do
But I have no clue what this is all doing.

[ShortKatz]

After some testing with different setting and sources, I'm now quite happy with the following settings in HandBrake:

Codec: AV1 10bit (SVT)
CRF: 26
Preset: 5
Profile: main
Level: auto
Additional parameter: enable-tf=0:film-grain-denoise=0:film-grain=8:mbr=10m (for 2D/3D animation change film-grain from 8 to 4)

The quality of the video is perfect (in some cases I like it more than the original), encoding is much faster than my x265 encodings and the file size is also smaller.

[Loomes]

Originally Posted by ShortKatz

Additional parameter: enable-tf=0:film-grain-denoise=0:film-grain=8:mbr=10m (for 2D/3D animation change film-grain from 8 to 4)

By setting film-grain-denoise=0 you are disabling film-grain=8, because film-grain sets the level of denoising and is not for preserving grain but the contrary, see https://gitlab.com/AOMediaCodec/SVT-.../Parameters.md . The name "film-grain" is very misleading here and it would have been much more user friendly if the level of denoise would be set directly in film-grain-denoise like e.g. film-grain-denoise=8.

Originally Posted by ShortKatz

The quality of the video is perfect (in some cases I like it more than the original), encoding is much faster than my x265 encodings and the file size is also smaller.

That's what I thought about preset 5 until I compared the result with preset 4 on my 48" OLED. Preset 4 is significantly better. Did you try some AV1 hardware encoding by any chance? I got a A380 last week and the results with highest quality settings and the encoding speed are stunning.

[quietvoid]

film-grain-denoise doesn't disable film-grain, it disables encoding from the denoised image.

[Loomes]

Originally Posted by quietvoid

film-grain-denoise doesn't disable film-grain, it disables encoding from the denoised image.

Okay, maybe I misread the parameter description but if film-grain-denoise=0 disables denoising and film-grain=n sets the level of denoising, what exactly would be the purpose of "film-grain-denoise=0 film-grain=8" ? Or in other words: How exactly would it effect the encoding result?

[quietvoid]

The denoising strength is still controlled by film-grain.
When disabling film-grain-denoise, it only encodes from the original image instead of the denoised result.

It would probably end up higher bitrate if the source video is noisy.

[Loomes]

Does this mean "film-grain-denoise=1 film-grain=8" would be 2-step process? First, film-grain-denoise=1 prepares a denoised image which is then encoded with film-grain=8 ?

[Loomes]

Thanks, I think I got it now. So film-grain foremost sets the level of grain in the video, which is also used as level for denoising if film-grain-denoise=1. Is that correct? If so, the parameter description is rather

FilmGrain: Enable film grain [0: off, 1-50: level of film grain, also used as denoising strength if film-grain-denoise=1]

Since there are levels from 1-50, it raises the question how to determine the level. Is this a pure subjective matter or is there some kind of technical indicator to determine the level? Thanks.

[quietvoid]

Usually the more noise there is, the higher film-grain would be.
I usually stay between 10-20.

[ShortKatz]

Setting film-grain-denoise=0 and film-grain=8 as a start is recommended in the SVT-AV1 CommonQuestions.
https://gitlab.com/AOMediaCodec/SVT-...rain-synthesis

As a general rule, a film-grain level of around 8 is sufficient for live action video with a normal amount of grain. Noisier video benefits from higher levels in the 10-15 range.

If grain synthesis levels can be manually verified through subjective evaluation or high fidelity metrics, then passing film-grain-denoise=0 may result in higher fidelity by disabling source denoising.

The effect of film-grain-denoise=0 can also be seen in this video starting at 9:00 min.
https://www.youtube.com/watch?v=5IV36FMpLqY

[benwaggoner]

Note that a lot of devices with AV1 decode don't support FGS, or have buggy implementations. It's not a safe "always on" feature at this point. Hopefully AVFG1 spec will catch on, and we can use FGS with VVC, and eventually a better version in AV2.

[Boulder]

Originally Posted by benwaggoner

Note that a lot of devices with AV1 decode don't support FGS, or have buggy implementations. It's not a safe "always on" feature at this point. Hopefully AVFG1 spec will catch on, and we can use FGS with VVC, and eventually a better version in AV2.

Then again, it is possible to remove the layer if it proves to be an issue.

[birdie]

Originally Posted by ShortKatz

After some testing with different setting and sources, I'm now quite happy with the following settings in HandBrake:

Codec: AV1 10bit (SVT)
CRF: 26
Preset: 5
Profile: main
Level: auto
Additional parameter: enable-tf=0:film-grain-denoise=0:film-grain=8:mbr=10m (for 2D/3D animation change film-grain from 8 to 4)

The quality of the video is perfect (in some cases I like it more than the original), encoding is much faster than my x265 encodings and the file size is also smaller.

Looks like you've never been interested in transparent encoding.

CRF 26 is a complete blurfest to me only useful for encoding anime.

[benwaggoner]

Originally Posted by Boulder

Then again, it is possible to remove the layer if it proves to be an issue.

Sure, but that can utterly change the look, as the source is denoised to use FGS, with FGS to replace the removed noise. Encoding for FGS but playing back without it can look really smoothed out and unnatural, and certainly wouldn't match creative intent.

If I can't count on FGS being used with AV1, I'd just encode AV1 without FGS. It'll increase the bitrate, but at least the visual appearance will be predictable.

AV1 and AV1 + FGS can almost be thought of as different codecs, and absolutely require different encodes.

[Boulder]

Originally Posted by benwaggoner

Sure, but that can utterly change the look, as the source is denoised to use FGS, with FGS to replace the removed noise. Encoding for FGS but playing back without it can look really smoothed out and unnatural, and certainly wouldn't match creative intent.

If I can't count on FGS being used with AV1, I'd just encode AV1 without FGS. It'll increase the bitrate, but at least the visual appearance will be predictable.

AV1 and AV1 + FGS can almost be thought of as different codecs, and absolutely require different encodes.

Unfortunately with modern codecs, everything is quite smoothed out without FGS no matter what settings you use. Believe me..I have attempted to remove all the filtering in both parameters and code and still there is horrible flat area banding left even at very low quantizers (like Q12 for aomenc). And I see people are using something like Q24, which must mean that there are no details left in the encoded video

FGS won't restore the details, in my opinion it just works very well at hiding the problems and fooling your brain into thinking that the material is sharper and more detailed than it is

[benwaggoner]

Originally Posted by Boulder

Unfortunately with modern codecs, everything is quite smoothed out without FGS no matter what settings you use. Believe me..I have attempted to remove all the filtering in both parameters and code and still there is horrible flat area banding left even at very low quantizers (like Q12 for aomenc). And I see people are using something like Q24, which must mean that there are no details left in the encoded video

Too much PSNR tuning, and to a lesser degree VMAF, can cause the flattening. This can generally be addressed with AQ tuning. It's an encoder limitation, not a codec limitation.

I've done comparisons between encoding AV1 with grain preservation without FGS versus FGS, and while grain preservation requires more bits than with FGS, with proper encoder and parameter tuning the perceptual results are pretty similar, and can match what's possible with x265.

FGS won't restore the details, in my opinion it just works very well at hiding the problems and fooling your brain into thinking that the material is sharper and more detailed than it is

FGS is best thought of as a creative intent preservation feature. If the source is supposed to have grain texture, the exact temporal and spatial location of each grain particle isn't important. So we can synthesize grain to preserve a similar creative intent and feel without having to encode the exact random locations of all those particles distributed randomly on any given frame.

And the metadata to describe the grain is a LOT more bitrate efficient than trying to encode all that high temporal and spatial frequency noise. For a premium quality experience, heavy grain can more than double the bitrate required compared the the same content without grain.

Content is going to look very different if it originally had heavy grain, but it was removed presuming it would be added back, but it was not.

There is one major flaw in the AV1 FGS implementation, in that grain particle size is rendered relative to display instead of content, so the size of a grain particle relative to the image changes. A fix for that is is in progress.

[ShortKatz]

Originally Posted by birdie

Looks like you've never been interested in transparent encoding.

CRF 26 is a complete blurfest to me only useful for encoding anime.

I'm very interested in transparent encoding. Seems we have different CRF 26, it's not a bluffest for me.