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AV1@Scale: Film Grain Synthesis, The Awakening

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Re: AV1@Scale: Film Grain Synthesis, The Awakening

#191

Post by liampulles »

The key point some people are missing here is that removing noise from a video before compression makes it more compressible. So if you compare a video compressed without denoising/degrading at bitrate X to a video that was filtered and then compressed at bitrate X with "fake noise" added later, then the latter will have edges and details that the former doesn't.

The principle of post-processing videos to add noise or sharpening is something that desktop media players have supported for years, some are even reasonably good at it.

Re: AV1@Scale: Film Grain Synthesis, The Awakening

#192

Post by fc417fc802 »

recursive wrote: post #168
fc417fc802 wrote: post #157

Earlier quoted context omitted.

TBF even as bloated as 48/24 FLAC is it's a rounding error at that point.

But FLAC is compressed. Don't forget 13 channels. Only the best! Probably 192 khz.

Lossless is lossless. But I shudder to imagine the file size of a 2 hour 13 channel 192/24 flac soundtrack.

However I notice a critical oversight on your part. You have assumed a channel depth of merely 8 bits when the minimum for a decent workflow is 12. Thus rather than 3.9 TiB (ie 4.3 TB) we arrive at 5.9 TiB.

Of course a modern feature length film is likely closer to 2.5 hours (7.3 TiB). Lossless HEVC should get that down closer to 2.5 TiB. At approximately 290 MiB per second that's going to demand dropping an SSD in the mail as the only practical method of distribution and playback.

Re: AV1@Scale: Film Grain Synthesis, The Awakening

#193

Post by PaulHoule »

As a mirrorless photographer I use a lot of processing to create a unique look. If I at all can, I set the aperture really small, use denoising, sharpening and color grading. If people think my photo came out of an old book that’s great.

I have looked at various “film look” filters and so far haven’t found one I like. When I think “film grains” I think of irregular shaped crystals, but most of the fake film grain I’ve seen makes a square pixel grain which doesn’t convince me at all. My understanding is the grain already exists before the image is shot in the sense that the films has irregular “pixels” which respond more or less because of shot noise and variation of the grain and I haven’t found anything that really simulates this.

Re: AV1@Scale: Film Grain Synthesis, The Awakening

#194

Post by FireInsight »

jedbrooke wrote: post #2

> This grain, formed from tiny particles during the film’s development, is more than just a visual effect. It plays a key role in storytelling by enhancing the film’s depth and contributing to its realism. I never understood the “grain = realism” thing. my real eyes don’t have grain. I do appreciate the role of grain as an artistic tool though, so this is still cool tech

It's funny, because I've always had a subtle visual snow that looks like a film grain on top of everything I see, and for a long time I thought everybody had it and that that's why artificial grain is added, to make pictures appear more realistic.

I've since learned that not everybody sees the world like I do, but I still do love to see grain and noise in pictures. Only RGB noise I often find dreadfully ugly when looked at up close, which is a shame, since that is exactly what most color cameras include.

Re: AV1@Scale: Film Grain Synthesis, The Awakening

#195

Post by barbazoo »

jedbrooke wrote: post #2

> This grain, formed from tiny particles during the film’s development, is more than just a visual effect. It plays a key role in storytelling by enhancing the film’s depth and contributing to its realism. I never understood the “grain = realism” thing. my real eyes don’t have grain. I do appreciate the role of grain as an artistic tool though, so this is still cool tech

Honestly to me it reads like a solution looking for a problem. I’ve never considered non deterministic imperfections that happen during recording of the movie to be essential to storytelling.

Re: AV1@Scale: Film Grain Synthesis, The Awakening

#196

Post by sneak »

UltraSane wrote: post #55
sneak wrote: post #38

Earlier quoted context omitted.

grain and 24fps and widescreen trigger certain contextual emotions around the movie-watching experience. remove them and your brain contextualizes the video very differently. this is likely the result of ~100 years of film-based filmmaking and projection. hell, we still call it filmmaking.

Yes, it is only the result of familiarity. We could gradually increase the frame rate of movies made in a year by 1 fps per year and then no one would even notice after 24 years every new movie would be 48fps.

No, it would take a lot longer than that. You’re fighting 100 years of tradition.

Re: AV1@Scale: Film Grain Synthesis, The Awakening

#197

Post by dylan604 »

account42 wrote: post #172
wbl wrote: post #86

Earlier quoted context omitted.

Movies are best enjoyed in the theater.

What, cramped into a room with tons of other people who can't help themselves from making noise or moving in front of you while you only have limited and overpriced snack options. As nice as a big screen and professional sound equipment is the downsides make the experience strictly worse than a big OLED + half decent soundbar.

You must live alone. Even at home, you have people called family or friends that do not necessarily sit idle while watching TV. Watching with kids at home is worse than at the movies because they are at home and don't have the same social rules to follow. People at home are also not under the social rules of not using their devices, and second screening has become the norm.

Yes, a theater probably holds more people than your typical viewing experience at home. Unless you go to the movies during the week and avoid crowds. The last movie I saw at the theater was on a Tuesday after opening weekend as 4pm. There might have been 2 other people in the entire theater. It was amazing.

Re: AV1@Scale: Film Grain Synthesis, The Awakening

#198

Post by dylan604 »

notpushkin wrote: post #143
rainworld wrote: post #74

Earlier quoted context omitted.

And yet here we are: DNR -> fancy grain -> DNR -> basic, approximated grain. Because noise doesn’t compress. And you get compression artifacts even in Blu-ray releases. What’s the point of applying fancy grain when what a lot viewers end up seeing is an ugly smudge?

I think at some point studios will give de-grained versions to Netflix directly.

At some point, it would not surprise me for Netflix to require this to be provided. While not negating what you concluded, I just think the impetus for the result is important to distinguish.

Re: AV1@Scale: Film Grain Synthesis, The Awakening

#199

Post by lossolo »

account42 wrote: post #186
lossolo wrote: post #105

When I watch an 80 GB 4K movie from Blu-ray, the last thing I want is film grain, which makes it look like a VHS recording from the 90s.

Film grain (real or artificial) is nothing like VHS artifacts.

It was an analogy. What I meant is that when I'm watching something in super high quality like a 4K Blu-ray, the presence of heavy film grain feels like a step backward visually, kind of like how VHS looked compared to today's standards. It takes away from the clean, sharp image I expect from that format.

Re: AV1@Scale: Film Grain Synthesis, The Awakening

#200

Post by UltraSane »

sneak wrote: post #196
UltraSane wrote: post #55

Earlier quoted context omitted.

Yes, it is only the result of familiarity. We could gradually increase the frame rate of movies made in a year by 1 fps per year and then no one would even notice after 24 years every new movie would be 48fps.

No, it would take a lot longer than that. You’re fighting 100 years of tradition.

You would notice 1 fps more per year?
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