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Realtime GPU Audio
CowboyRobot writes "Two researchers at San Francisco State University has successfully implemented hardware acceleration for realtime audio using graphics processing units (GPUs). 'Suppose you are simulating a metallic plate to generate gong or cymbal-like sounds. By changing the surface area for the same object, you can generate sound corresponding to cymbals or gongs of different sizes. Using the same model, you may also vary the way in which you excite the metallic plate — to generate sounds that result from hitting the plate with a soft mallet, a hard drumstick, or from bowing. By changing these parameters, you may even simulate nonexistent materials or physically impossible geometries or excitation methods. There are various approaches to physical modeling sound synthesis. One such approach, studied extensively by Stefan Bilbao, uses the finite difference approximation to simulate the vibrations of plates and membranes. The finite difference simulation produces realistic and dynamic sounds (examples can be found here). Realtime finite difference-based simulations of large models are typically too computationally-intensive to run on CPUs. In our work, we have implemented finite difference simulations in realtime on GPUs.'"
What does it sound like when you strike a neutered cat with graphene carrots of varying length?
Something to do with all those GPUs when ASIC mining of Bitcoin takes over. It's going to get noisy.
" simulate nonexistent materials or physically impossible geometries"
the sound of one hand clapping
When will you people LEARRRNNNN???????
Maybe when there is something to learn? Both forms are in common use, including physics textbooks and papers.
resonant frequency n. Physics a frequency at which resonance (of any kind) takes place.
1897 L. Bell Electric Power Transmission x. 393 When the [electrical] oscillations are strongly damped by the presence of iron, the total resonant rise is considerably diminished, but it varies less rapidly as the resonant frequency is departed from.
1934 J. P. Den Hartog Mech. Vibrations ii. 52 The forced frequency coincides exactly with the natural frequency... This important phenomenon is known as ‘resonance’, and the natural frequency is sometimes called also the ‘resonant frequency’.
2001 S. Hawking Universe in Nutshell ii. 52 (caption) Just like the strings on a violin, the strings in string theory support certain vibrational patterns, or resonant frequencies, whose wavelengths fit precisely between the two ends.
Looks like you need some GPU acceleration to handle realtime first posting.
I think what's most important is now we have the mathematical models in place that allow us to simulate convincing sounds rather than "sample and include". For the creative types, this will save a ton of effort and money. It also has implications for games, e.g. with the given environment model, be able to produce convincing sounds in real-time rather than taking sound samples mixing them with reverb, attenuation, positioning, etc.
Careful with names containing L slashdot.org/~AiphaWolf_HK slashdot.org/~AlphaWoif_HK slashdot.org/~AiphaWoif_HK
You just need to parse the sentence correctly --- perhaps the name of the university is "Two Researchers At San Francisco" State University.
Actually I think this is pretty cool. It's always bothered me how repetitive sounds can get in games, it would be a neat trick if you could model object's for sound the way you model them for graphics. Each door, window, rock, etc, could have a subtly different sound from the one next to it. I'm sure they're not to that point now, but they are spelling out the possibilities.
What do they mean by "physically impossible geometries"? Are they talking about things that have a higher or lower number of physical dimensions (eg: a 4 dimensional object or a 2 dimensional object)? A weird combination of Euclidean and non-Euclidean geometry?
Dear anonymous moron,
Established use of a term is what gives it definition. That's how language works. if we decided that "cow" is a small bird that's delicious, then that's what a cow would be.
News at 11.
Now that definitely sounds like the most interesting application of this technology. Organic-sounding-artificially-made sound effects.
This just in: paper author commits suicide now that slashdot poster not interested in his life's work.
I'm an Engineer, and this is the first time in my life I've heard "Resonance" and "Frequency" in that order.
I studied that stuff for a while. Had some tests on it. Read some books on it. Look into it at work.
I'm also a bit of a musician.
I'm not saying you're incorrect -- I've just never heard that phrase before.
---
ECHELON is a government program to find words like bomb, jihad, plutonium, assassinate, and anarchy.
I'm also excited by this. Especially as to what this could mean for Text to Speech. Generating more organically modeled TTS could really push it out of the uncanny valley. Currently if you ask a tts engine to say a word or phoneme, it is identical to the last time it was made. What if it were generated in realtime with the same variances as a human voice.
Because you can - or because you should?
One of the fundamental problems with computer based music production is that we're still, unless we're working with synthesized music, limited to pre-recorded samples.
Vienna Symphonic Library, for example, is well over several hundred gigabytes in size, many of those samples covering various articulations (playing techniques) of the same instrument.
One set of violins playing legato. One set of violins playing pizzicato. Marcato samples etc. etc. With virtual instruments that is no longer necessary. We can just "tell" the virtual musician where to place his fingers and how to do that and cconfigure a bunch of presets for the composer to use as he wishes.
One fundamental problem at the moment is dealing with smooth transitions from one note to another in sequence. For example the violas of a real orchestra playing a transition from one note to another would slide between them smoothly. This CAN be simulated by changing the note pitch digitally, but that loses authenticity.
VSL solves this by pre-recording the musicians playing the most common note transitions. This is a huge undertaking and takes up a lot of space as you have to record C to C#, C to D, C to D# etc. etc.
If we can simulate the instruments without relying on samples we can do away with all that and create some truly amazing things for musicians. I suspect that in the future we will have synthesized orchestration packages so that we can do away with samples entirely.
I was thinking that it would be good for mapping out real "surround sound" similar to how complex reflection and/or ray-tracing is done.
Even if the initial sounds themselves are canned, the sound through a wooden hallway, a hallway with a carpet, or a large open room would be different. Combine that with digital surround and it could be quite useful.
I think what's most important is now we have the mathematical models in place that allow us to simulate convincing sounds rather than "sample and include". For the creative types, this will save a ton of effort and money. It also has implications for games, e.g. with the given environment model, be able to produce convincing sounds in real-time rather than taking sound samples mixing them with reverb, attenuation, positioning, etc.
Yes, absolutely! I see it as analogous to vector graphics vs bitmapped graphics. Vector audio is THE holy grail of accurate sound reproduction.
If these guys can pull this off, it will be the literal (digital) equivalent of having your own live performance - every time! You will have software based models of various instruments that will play music for you by playing their respective instruments for you real-time. The possibilities of this are actually astounding. You would record or store music not as digital samples (lossy, lossless, notwithstanding) but in terms of *how* each instrument is played. You have now turned the problem on its head - you are constrained by the accuracy of your software/mathematical model of each instrument, and by how well you are able to control it to become more nuanced. At a hardware level, if you assume infinite processing power, the challenge would be to accurately play these software instruments. You could again take a completely different approach - you could for example have an array of speakers where each speaker is dedicated to playing a specific instrument, and all the speakers are fed separate audio signals.
Contrast this to the currently audio setup - which would be a 2.0 or 2.1 or 5.1 or 7.1 stereo/HT setup - where each speaker tries (and fails) to accurately reproduce the entire audible frequency spectrum, or you have a mish-mash setup where different speakers divvy up the frequency spectrum between themselves (think sub-woofer and satellite speakers) so they can do a marginally better half-assed job.
If you look at the entire chain in a traditional setup, you have the speaker driver's mechanicals, the speaker crossover electronics, the speaker wire, the power amp, the pre-amp, the DAC, the player, the source audio signal (mp3, flac, redbook CD etc.), the recording mike, and the recording room - all of these links in the chain distort the music in their own way.
What I mentioned above is only my interpretation of how this technique can be used -there are a huge number of other possibilities - software defined objects, such as in games, can now have their own (genuine) sound, and that will sound different depending on how you interact with them. You could also have virtual instruments, unconstrained by the laws of physics, define their own physics and their own unique sound. You could even program room acoustics and have the instruments play sounds as if it was being played in open space, a large hall, a studio, on a beach etc.
Sigh.
...perhaps it would be easier to visualize it? The frame buffer is just one bit-throw away...
4wdloop
I could care less how many people tell me it is legitimate.
FTFY.
systemd is Roko's Basilisk.
You do realize this is research and not a product, don't you? As in, hey look what we discovered we can do!
If you want it ported to Linux using AMD GPUs, request the source code (since that's the only way it's provided) and port it yourself.
I void warranties.
They're not talking about processing in the sense of DSP, they're talking about synthesis of sound waveforms simulating physical models of the instruments. Any DSP would come after that.
I void warranties.
[Damp vs dampen (vs moisten)]
Look, I LIKE my sonic disturbances to come with a little added moisture, ok? Is that so wrong?!
Same with my inertia! Dry inertia is just erosive as hell, and very uncomfortable!
I don't *care* that those are both things that fudamentally cannot be made moist. I want to dampen them anyway!
(Lol!)
As a pedantic engineer, I beg to differ. A frequency can very much resonate, just not the way you're thinking. Ever seen any scary movie from before 1980?
"I WHOOOOOSH how many people tell me it is legitimate."
FTFTFTFY