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Comment by nsxwolf | Hacker News Reader

I don't have much physical media since finally going 4K HDR, but so far my experience hasn't been great. I purchased the Mission:Impossible boxed set, and it came with a download code to use on iTunes.

The discs look like trash. Noisy, grainy, just bad. The iTunes versions look phenomenal.

It would be nice if there was a way to know how good the quality of a particular release is before buying it. Reviews I read don't seem to go into a lot of detail. I realize it's probably somewhat subjective and hard to put into words how an image looks.

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Wow, that's really surprising and disappointing. Usually the disc is considered the ideal "canonical" way to watch the movie, but I guess not always. I think blu-ray.com has user reviews that are focused on the quality of the disc specifically, but I usually don't look at them. I looked at MI:1 and they talked a lot about the grain, but seemed to see it as a stylistic choice.

Film grain from pre-digital era movies is a divisive issue. All older movies originally had some amount of film grain from the analog film. Some people like it and want it there on purpose. Some people prefer the movie run through a de-noise filter. The pro-grain people claim this removes fine detail. The anti-grain people say why the hell would you want it there on purpose. Some modern movies even add film grain on purpose. See Disney's Luca as an example. I personally don't care for it but it usually doesn't bother me as long as it's not extreme.

"Noisy, grainy, just bad."

AKA, it was shot on film. Film has film grain, which can only be removed by Digital Noise Reduction. DNR removes film grain, but also scrubs away detail and can leave waxy faces among other artifacts, as well as a fairly artificial and non-cinematic look. Film grain compresses very badly over streaming, so DNRing the streaming version before compression is probably what you are seeing. In this case, you prefer the DNR - but if you read online forums, most collectors hate it and consider it a crime against humanity to have ever been invented.

Which explains the downvotes I'm getting. I've apparently angered the cinephiles.

Edit: I'm bemused that my subjective personal preferences have made multiple people this upset.

Or maybe you're getting downvoted because you were denigrating other people's personal preferences when you called the disc version "trash." You're guilty of what you accuse others.

I think you're getting downvoted because the solution to your issue was one "why does my bluray look grainy" search away, yet you chose to stay uninformed on purpose and complained about it in a public forum without understanding the mechanics.

It’s funny if the poster is actually complaining about grain. Digital compression, like the one that Netflix uses, will often clean up the image of grain as a secondary effect of the compression algo.

Essentially grain is a lot of detail that video compression algorithms have been taught to ignore/remove. H.264 was notorious for virtually removing all grain making it impossible to have authentic film grain on YouTube for years. (I work in advertising).

Exactly like you said - grain is a common first victim of video compression.

The other curious thing - modern movies that are shot on film / have grain actually get it removed during VFX stages. You have to do it so you can integrate CGI - grain is usually “sampled” first by the compositing software (The Foundry’s Nuke in 99% of occasions) and removed since the CGI image won’t have any grain from the CG renderer so you have to integrate it onto a denoised image. You then re add it at the end!

Using the same software you then re-add the sampled noise back onto the image, and since you’ve now integrated the CGI, the noise goes on top of everything helping it all get integrated.

Just saying this because you are right - using noise reduction to remove film grain for release is considered a sin (I myself would agree with the sentiment). Yet actually most films today will go through some denoise stage in VFX. Which is an interesting thing to think about - we actually remove the grain for a lot of the work then re add to keep the filmic texture.

I wonder: If film grain never existed, would we invent it? If we had originally developed film technology where everything looked completely clean, would anyone have thought "Hey I've got a great idea, let's figure out how to make this look grainy"?

I doubt we would invent it. But there are artefacts of the analogue age that have more value than people think. My understating is that “grain” on vynil is perceived as increased resolution to the brain (or so I’ve read). Thus giving some scientific reason for the preference of audiophiles. It would be interesting to know if there’s a similar effect to grain in film but I don’t know.

The other interesting thing is how beautiful and different grain is when it’s from silver halvide film. I’d dare say it’s truly gorgeous to watch. Such film was used in the 1900-1930s age and if you watch a great print or restoration of that time the effect is quite stunning. I believe John Ford’s Stagecoach is a good example that should be relatively easy to find.

unfortunately I think the same epoch has lost immense amounts of film due to the flammability of the materials (which is extremely high, as seen in Tarantino’s Inglorious Basterds). Which is why every once in a while you’ll get a huge fire in some film archive and so much of it is lost.

If film grain never existed, would we invent it?

Yes, but it wouldn't be used across an entire film. Likely just in flashbacks and other dramatic scenes, the way it's applied to digital productions today.

Similar to how in the 2000's, hipster bands added photographic pops and crackle to their tracks as an artistic measure.

They added those things to indicate age my mimicing older formats. They wouldn't add those effects to mimic older formats if older formats never existed.

I don't think we'd recreate film grain, but I think some form of artifacts would exist and people would eventually grow a taste for them.

Modern digital music can be completely clean and flawless. But it can also have some weird artifacts that can only exist digitally, like aliasing, stuttering from a corrupt file or skipping CD player, compression artifacts while streaming or from very low bitrate sources.

And nowadays we're seeing genres like Hyperpop, Glitch Hop, and Future Bass which all play with these artifacts.

Flume even has a song[0] where you can hear the distinctive whine of an improperly grounded USB audio interface. It's inserted into a silent part of the song, so it is 100% intentional and not an accident in the recording. I like to think he's giving a little wink-wink to other music producers.

It's on the "My Name is Flume Mixtape" album, which itself is a great example of intentional digital artifacts in a creative use. There's lots of aliasing on things that shouldn't, and things that "should" alias like square waves sliding into the 10khz range are perfectly alias free.

[0] Amber at 1:51. The ringing sound that comes in after the first bass hit is also some sort of ground noise, but very distorted.

https://youtu.be/RM2cNhVep40

Agree, just thought I'd mention that there are zillions of plugins to add these kinds of distortion/noise (like vinyl noise, ground noise, tape distortion, etc). Eg Devious Machines Texture, U-He Satin, etc, etc.

Also most modern synths have noise oscillators for this purpose (eg Serum, Pigments, etc, etc).

Things just sound too clean and perfect/boring if you don't use some kind of saturation/noise or distortion for ear candy.

As an aside, I'm pretty sure Skrillex puts CamelPhat on his master bus. The music video for one of his songs was his Ableton set and it was shown in there.

Good point, I should have emphasized that it can be perfectly clean, but it often sounds like it's missing something, so it's usually made dirtier afterwards.

I just wonder if the reason it sounds like it's missing something is because subtle noise and saturation sound objectively better to human ears, or if it's just because that's the precedent that's been set and we've grown fond of it. Early music was recorded to tape by necessity, and the digital era tries to bring those subtle distortions back to sound like it. Even a teen who has never listened to older music recorded to tape still listens to modern music that tries to sound like it was recorded to tape or passed through saturating transformers.

I think the uptick of intentional digital artifacts in music shows that we grow fond of what we're used to experiencing, even if it's considered a negative in an objective sense. But we can't ever really prove that without a separate society that somehow skipped the entire analog music (or film) era.

Also yeah Skrillex really breaks all the typical rules but his mixes sound fantastic (or garbage, depending on your opinion. His stuff is really divisive). The hosts of The Mastering Show podcast thought his youtube video was fake because of how much saturation and limiting he uses. I'm pretty certain it's totally real.

I think it's because we've evolved in nature to appreciate natural sounds, which always have distortion, harmonics and noise.

There's nothing that would generate perfect sine/sawtooth waves or perfect, undistorted echoes. So anything else just sounds unnatural/robotic.

I think it's the same with film grain, looking at flat perfectly polished surfaces can seem boring and unnatural to the eye.

Perhaps. Eyes do have "film grain" in low light conditions.

> H.264 was notorious for virtually removing all grain making it impossible to have authentic film grain on YouTube for years.

In the YouTube case, the low encoding bitrates make it really difficult to encode fine detail. (Blu-ray discs use H.264 as well, and at those bitrates it reproduces film grain well.)

> Which is an interesting thing to think about - we actually remove the grain for a lot of the work then re add to keep the filmic texture.

This is a great point. Even with older "remastered" movies, analog artifacts like film grain are sometimes removed during cleanup and then recreated during mastering.

They will 100% remove grain for restoration. It’s the same process as VFX really, essentially restoration involves a lot of what’s called “cleanup” work in the industry. In a Marvel movie cleanup will be removing wires from actors, in restoration it’s scratches and other issues.

It sounds like movies need to start including gpu shaders with them to add grains or other effects regardless of the compression.

Not literally a gpu shader but AV-1 now has film grain synthesis as part of the decoding process:

https://waveletbeam.com/index.php/av1-film-grain-synthesis

Netflix removes the film grain in compression then adds it back in: https://www.slashcam.com/news/single/Netflix-removes-movie-n...

Aren't films usually shot at higher resolutions (5K to 8K) so DNR or not you are going to throw away information during the editing/mastering process even with 4K output.

I'm not a collector, but I hate vaxy faces. Which is also the reason I could spot CGI for years, until we had the ability to simulate even a pores of skin, but then again it were tuned to 11 and I could spot it again.

It's not just extra DNR applied, modern image and video compression formats almost make it a point to erase all detail and texture from images.

For example, compare the WebP and AVIF (VP8/AV1) compression artefacts with JPEG (and MPEG).

With WebP and AVIF all textures and low contrast details tend to be erased or smoothed out, preserving only high contrast parts of the image.

The JPEG image may have some visible ringing and block edge artefacts, but at least the textures and fine details are preserved!

I've noticed that too with cwebp (and other libwebp-based tools) encoding for darker images. My guess was that they their difference function is using the wrong colorspace so it does not match the perceptive difference. My quick tests of cjxl fared much better so all hope is not lost.

But essentially, losless compression is all about throwing away impercetible details. Noise is an interesting case here because the presence and fequency of the noise (the texture) is significant to the viewer but having the noise match 1:1 is not. Which is why newer codecs remove the noise and then re-add generated noise during decoding.

On the other (semi-unrelated) hand, film can be much, much better than digital for some applications. For example, a transmission electron microscope that uses an emulsion film to capture the image compared to a digital capture device - the film can be magnified again with a light microscope later for much more magnification than may be accessible when all of the information is registered to a single pixel.

Just something to remind us that there are pros and cons to everything.

There are sites who do this exact kind of review.

https://www.google.com/search?q=review+picture+quality+blura...

Film grain is a funny topic... if it was the original look then it can be considered highest quality/fidelity to retain it. Filtering it makes for easier video compression.

This is a totally uninformed question. Are you sure the bad quality from the discs is the fault of the discs rather than your blu-ray reader? I'm assuming you've had good quality from the reader for other discs??

It's a digital signal, either it reads and works or it doesn't. You don't lose quality because a "bad" player.

That's oversimplifying things. Players and TVs can and do apply their own processing and then there are sometimes parts (e.g. Dolby Vision) that are just ignored by non-supporting players.

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