The VideoLAN Forums

A "film grain" filter that adds noise would dramatically improve the perceived quality of live-action movies with a minimal amount of CPU cycles. Is there a reason why such a simple and useful video filter hasn't been implemented? MPEG-4 and even DVD video often have trouble compressing film grain effectively, resulting in blocky areas that could be smoothed out by adding a light amount of noise.

Some quick examples of what I mean, without grain:



And with grain, which brings the image closer to how it would've looked when it was originally projected from film:



You can also enable Noise in FFDshow in Media Player Classic (select Mplayer Noise and turn everything else off) to get a better idea of how this looks in motion.

It's called post processing and there are 6 levels.

It's called post processing and there are 6 levels.

Post processing takes out compression artifacts. I am talking about adding noise to bring back to the appearance of actual film. I edited the original post to make that somewhat more clear.

Hmm! Thanks but no thanks!

Even the film manufactures are trying to do away with this and slowly doing a rather good job of it too. I suppose you still like vinyl disks too?

It isn't too hard to implement. There are open source filters for that. But there are also needs for other filters (lancoz resize, blur, sharpening etc).

Hmm! Thanks but no thanks!

Even the film manufactures are trying to do away with this and slowly doing a rather good job of it too. I suppose you still like vinyl disks too?

Actually what is being worked on is to signal to the encoder that the picture grain is intentional and that is should not be removed in the pre-processing filter. To carry the information in-band for the decoder to actually retain the "film grain" that was intended as part of the artistic work involved in the picture.

Considering Vinyl audio disks are now more than 20 years since there production they are historic so we should keep the scratches an a part of the historic remembrance of a by gone era??? This is just to weird for me to consider! While there may be some who actually want this, I am not one of them! Next someone will be saying, (as interlaced video disappears) that we should not provide deinerlace filters because it takes away from the nostalgia of a by gone era.

Considering Vinyl audio disks are now more than 20 years since there production they are historic so we should keep the scratches an a part of the historic remembrance of a by gone era??? This is just to weird for me to consider! While there may be some who actually want this, I am not one of them! Next someone will be saying, (as interlaced video disappears) that we should not provide deinerlace filters because it takes away from the nostalgia of a by gone era.

Do you even watch movies in a theater? Do you even listen to music from the analog era? It is not about preserving superficial flaws like dust and scratches, but retaining the original texture of the recording as the director/producer intended. Even a simulation of it is perceptually more pleasing than blocky artifacts and/or smeary post-processing. Film grain is not going anywhere; watch any of the HD trailers on Apple's site to see that. Even movies shot in digital have grain added to make them appear more cinematic.

I practically grew up on the TBS lot in Burbank CA and have helped build production and post production facilities round the world. While I'm not old enough to remember silent pictures, I do know that cinematographers, producers and or directors do NOT want film grain or scratch sounds (noise that was not intended) on their product. The notion of preserving this is just foolish by people that believe the hype and jive of Hollywood and or want (love) nostalgia.

I'd rather have film grain than pixellation any day, unless you can give me a way to use a ccd the size of a large screen tv so that I can record something with quality enough so you can't see pixels or processing on a big movie theatre screen.

That said, adding fake film grain to a digital image is silly. You cannot make it look as it originally did because pixels are square. Sure, it would be nice to have as a teaching tool, but the film grain is most likely there in what you are watching, you would just have to have a much much much higher resolution digital version in order to see it.

So what are we supposed to do, run all of our film through noise reduction algorithms so that everything looks like a smeary, digitally perfect mess? You seem to be quite the contrarian about what would be an optional, user-selectable feature that would be more useful than the "psychedelic" filter. The point is merely that noise is a viable and simple post processing option and one that ffDshow has already had for a long time now.

I didn't intend this to turn into some useless debate on vinyl versus CDs.

I'd rather have film grain than pixellation any day, unless you can give me a way to use a ccd the size of a large screen tv so that I can record something with quality enough so you can't see pixels or processing on a big movie theatre screen.

That said, adding fake film grain to a digital image is silly. You cannot make it look as it originally did because pixels are square. Sure, it would be nice to have as a teaching tool, but the film grain is most likely there in what you are watching, you would just have to have a much much much higher resolution digital version in order to see it.

I'm not really sure what world your living in?? If the film manufactures were not constantly improving the quality of their product they would have lost all of their clients who presently do most of the post processing digitally and the end product is put back on a film chain. It's easy to see poor film in the newer resolutions. Even with all this in place many of the productions you watch now are being shot digitally and have never seen film until the mastering process.

So what are we supposed to do, run all of our film through noise reduction algorithms so that everything looks like a smeary, digitally perfect mess? You seem to be quite the contrarian about what would be an optional, user-selectable feature that would be more useful than the "psychedelic" filter. The point is merely that noise is a viable and simple post processing option and one that ffDshow has already had for a long time now.

I didn't intend this to turn into some useless debate on vinyl versus CDs.

I'm not sure what world your living in either or what you are watching. If it weren't for the newer HD resolutions film manufactures would have no need to continue to improve their emulsions. Some years ago TI created DLP projectors for Digital Theater and demonstrations of this technology swept Hollywood, Film lost. We would have Digital Theater if it weren't for the cost. However there are some (65 or 70 last count I heard) theaters world wide. But most of the production houses do use this technology and there is no film involved. Today we have cameras that shoot the scenes digitally and more and more productions are being done this way as it is more cost effective than film and the product or creativity does NOT suffer because of the use of it. In fact it benefits for many reasons like avoiding the Telecene process in which the Telecene artist had to match film batches to keep the color consistent throughout the project. This was (still is) an expensive difficult task which must take place when film is used to guarantee that special effects can be matched and editors can freely edit the product. Part of the Teleciene process is keeping the film clean. This means Low noise with the least amount of film grain possible. One of the first things a cinematographer does at the beginning of a new project is call the post house and asks about the latest advances in film stock. This is of coarse dependent on if the producer has chosen to shoot the project is using film, as this is becoming more rare as the cameras continue to improve each year.

I have re-read this post and perhaps I was a bit to harsh in expressing my opinion even though I feel strongly about the topic. With each new technology there are hold outs who prefer the older technology and really, there is nothing wrong with this as it ends up a personal preference. In general a film look is softer with not as much detail. This is being proved in mega pixel ratings for still cameras, yet some don't see the difference and don't care to pay the higher price. Adding noise or film grain however, just seems to be moving to far back in time. But, of coarse the source code is available and changes, additions and or patches are always welcomed here.

OK.

Please stop fighting on that issue

This filter could be a good idea if you want to code it. But, as DJ says, a lot of developers don't seem to be interested in this. So, coding filters is not so difficult, please, code it, and give us the patch on the vlc-devel mailing list and if it fits the quality needed, it will be incorporated in VLC.

I have all respect for those in the industry trying to perfect movie quality. They should pursue that route.

However, when watching movies made in the late 70s / early 80s, somehow you get 'into' the movie due to the grain caused by the equipment used in recording/processing it. Much like a 60s song (even remastered on a CD) can 'take you back'. A Beatles song sounds the way it does largely due to the amplifier technology available then.

Both industries know this, and many try to emulate it. Special effects scene material is intentionally degraded to not become too obviously perfect and fake. 60s amplifiers and mixing boards command a high price to 'get that guitar sound'.

But that's not the point here, I think.

1. Not all movies are perfectly encoded, resulting in smearing and pixelation, especially on computer screens of high quality. (VLC is a computer app, remember? )
2. For example, Star Wars episodes 4-6 have been so polished as to rob it of its magic - sets and effects are so perfectly reproduced as to not give the illusion of reality that was originally intended - 'hey, nice styrofoam beam / plastic crate".
3. tonsofpcs mentioned emulating the original film grain is impossible, "because pixels are square". Not so. Lots of movie editing software have algorithms to emulate different kinds of cameras, as do 3D rendering packages used in the movie industry. Now why (FCOL!) are those filters there?

The gist of it I guess is that some people dislike artifacts and would like a possibility to mask them/make the overall impression more forgiving with a film grain. Not-perfectly-encoded films just look better that way. I'd say 50% of the DVDs of movies made in 1985 have awful encoding.

I registered and posted this because I feel strongly about the experience of being sucked into a film, rather than a watcher of it.

I'm a strong advocate of VLC player (because it 'just works!'), and I thought it was obvious that the leading movie player would have such a filter, at least third party. I was let down.

Patches are welcome

I mean it. No developers is against any filter addition. We just don't have the time to do all of them. So, 3rd party submitting is the way to go

Great to hear

I don't consider myself skilled enough in cpp or filter algorithms, or I would do it myself. Let's hope a coder sees this thread and sees both viewpoints. And agrees with me and the original poster

You might be interested in this thread: viewtopic.php?f=2&t=39321&p=122560#p122560 . I'd appreciate comments on the general look and feel of the snapshots mentioned in the last post.