force transcode to av1 - Printable Version

force transcode to av1 - Printable Version

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+--- Thread: force transcode to av1 (/t-force-transcode-to-av1)

force transcode to av1 - Ember - 2023-08-11

is there a way to force the server to transcode to av1?
my upload speed is not great, so getting the client to request a more efficient format would be very helpful

RE: force transcode to av1 - toytown - 2023-08-11

I don't think so in the current version.

Also from the last tests i've seen (about 6 months ago) with hardware encoding Nvidia was practically the same quality with their H265/AV1 (Quality Profile 10Bit) encoding using Nvidia 4000 series.
On Intel (Quality Profile 10Bit) H265 actually offered better quality for the same bitrate over their AV1 Encoding in the Arc series cards. So at least with this generation of GPUs i don't think AV1 transcoding is worthwhile.

Of course software encoding will give better results, but the CPU requirements are off the charts.

RE: force transcode to av1 - bitmap - 2023-08-16

(2023-08-11, 11:45 AM)toytown Wrote: I don't think so in the current version.

Also from the last tests i've seen (about 6 months ago) with hardware encoding Nvidia was practically the same quality with their H265/AV1 (Quality Profile 10Bit) encoding using Nvidia 4000 series.
On Intel (Quality Profile 10Bit) H265 actually offered better quality for the same bitrate over their AV1 Encoding in the Arc series cards. So at least with this generation of GPUs i don't think AV1 transcoding is worthwhile.

Of course software encoding will give better results, but the CPU requirements are off the charts.

I mean quality isn't the metric that AV1 is made to compete on. It's quality for bitrate and AV1 wins almost every time, save for a few niche cases. Additionally, AV1 being an open codec is a huge plus over HEVC. There are flaws, and while I was just getting my x265 encodes pretty flawless (and fast with QSV), I've jumped ship to AV1 instantly looking at the quality, size, and knowing it's an open standard. Even though it's slow, with interesting tools like ab-av1, you get what you're looking for 100% of the time.

RE: force transcode to av1 - Venson - 2023-08-16

Hey @Ember
Short: no
Long: still no

The client decides on what and when to transcode and i am not aware of any client (apart from JMP trickery maybe) that allows you to force a specific codec to transcode to.

RE: force transcode to av1 - toytown - 2023-08-16

(2023-08-16, 08:12 AM)bitmap Wrote: It's quality for bitrate and AV1 wins almost every time, save for a few niche cases..

The Intel QSV AV1 hardware encoder loses to the Intel QSV H265 hardware encoder in almost all instances, not by much but still, no point in using it if its inferior. This doesn't mean the codec itself is worse, just with this interation of GPUs it might not be worth making the change (if you only care about transcoding quality)

https://imgur.com/a/61fyhgf (purple line is QSV AV1 10Bit Quality output vs QSV H265 10Bit Quality on Intel Arc)

RE: force transcode to av1 - bitmap - 2023-08-17

(2023-08-16, 11:19 AM)toytown Wrote:
(2023-08-16, 08:12 AM)bitmap Wrote: It's quality for bitrate and AV1 wins almost every time, save for a few niche cases..
https://imgur.com/a/61fyhgf (purple line is QSV AV1 10Bit Quality output vs QSV H265 10Bit Quality on Intel Arc)

I don't think there's enough info here to make the claim you've made but I'm also just getting into my own investigations. For *encoding* AV1 wins, hands down. On the fly is a different use case, however. Hardware encoders for AV1 are limited right now and my experience is zero as my A380 is still in the box waiting for me to get home from a business trip. This graph is an isolated use case without resolution, parameters, etc... or an attempt to limit what bias might be there. It may be correct data for 1080p 10-bit SDR at constant quality or something similar.

But when you take into account something like the flexibility of de-noising/film grain synthesis of AV1, the excellent compression you can get on 4K HDR or SDR content, the difference in how you approach the encoders versus x265, it becomes a little bit of a different ballgame and it's hard to compare apples to apples. It's also true that if you're looking to have 4K DolbyVision content, AV1 isn't your codec (yet?).

I guess I concede your main point that it's too early to really say, on the topic of transcoding, which codec wins the day. But with AV1 being new-ish, having very little support on the hardware encoding front, and still producing those pretty impressive results in comparison to a codec that has been around for an extremely long time, it seems like AV1 is without a doubt the direction of streaming media in the future.

RE: force transcode to av1 - Revv23 - 2023-08-17

It is my understanding that the client determines what the server serves, not the server.

Of course the server needs to be able to deliver what the client asks for.

The only client I am aware of that lets you force a certain type of transcode is the desktop client.

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