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Show HN: Entire concerts algorithmically "reconstructed" from YouTube videos

switchcam.com

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Re: Show HN: Entire concerts algorithmically "reconstructed" from YouTube videos

#101

Post by jurre »

brettwelch wrote: post #34
angusgr wrote: post #3

Wow. Many thoughts arose: - Is this more, less, or equivalently legal (copyright-wise) to just posting the youtube videos on youtube in the first place? It seems like the act of compositing them in this way would be significant, but maybe not? - The normalisation of audio could use some work. SwitchCam seems to do something (the youtube volume on each clip was different for me), but it didn't quite work. - I'd be rea…

Thanks! - I'm no lawyer, but the advice we've received is that we're good on the legal side. - You're on the money re: audio. It's miles better than it was 1 month ago, but we're still not 100% yet. - There is a human curation step (~5% of the process), but that is mostly for removing really crappy videos. Searching/Synching/Sequencing is automatic. - I dunno about next step(!), but i agree the idea is super interest…

Maybe this is something that has been mentioned before, but I would love it if I could select a fixed audio from one of the videos. For most videos theres one audio track thats clearly the best and it would be great if I could listen to that one the whole time while switching camera views. PS: Very cool stuff!

Re: Show HN: Entire concerts algorithmically "reconstructed" from YouTube videos

#102

Post by b1daly »

allbutlost wrote: post #80
jackpirate wrote: post #77

Earlier quoted context omitted.

If you haven't captured any frequencies above 15kHz (which an average cell phone mic is unlikely to do), no amount of averaging, filtering, or combining will get them back. I think this is technically not quite true. If two cell phones right next to each other are both sampling at 15kHz, in the best case you could combine their samples to get an equivalent sampling of 30 kHz. (Best case meaning phone 1 samples exactl…

This is unfortunately so unlikely to as to be practically impossible (currently!). If the microphones, ADCs etc on both phones are incapable of capturing frequencies of above e.g. 15Khz below a certain range, combining those signals definitely won't bring you any closer to the original signal. You may be able to cancel out a fair bit of noise given enough processing but you won't get back what hasn't been originally…

15khz is actually is very high frequency, most adults can barely hear it. The audio from phones is probably much more band limited than that. But that's the least of the challenges. People listen to and enjoy highly band limited music all the time: laptop speakers might have a frequency response of 500hz - 4khz.

The more challenging problem is the distortion from the phones being overloaded, crowd noise, built in limiters, different sample rates and compression. It is true that phase relationships from a single sound captured by multple sources can be very problematic.

However, the further the mics are away from the source the less this a problem at least with "phaseyness." This annoying artifact is a type of comb filtering , and it's based on the fact that two mics close to a sound source can be thought of really capturing the "same" sound at slightly different times. If the mics are far apart, the sound is no longer the same: it's picking up reflections from a myriad of sources, the phase relationships within the frequency spectrum have been smeared and shifted by traveling through air. This negates a lot of phase problems. The more likely problem is cancellation in the low frequencies which can be ameliorated with time alignment.

Re: Show HN: Entire concerts algorithmically "reconstructed" from YouTube videos

#103

Post by stuaxo »

baddox wrote: post #37

Cool idea, but I was sad that it wasn't finally an implementation of an idea I've had for a long time. My idea is to actually use video and audio information from distinct sources to create a single video/audio stream that is of better quality and/or completeness than any of the constituent parts. Essentially, my idea would do to video what Photosynth does for photos. http://photosynth.net/

I've been thinking the same thing about audio for donkeys years. ..

Re: Show HN: Entire concerts algorithmically "reconstructed" from YouTube videos

#104

Post by stuaxo »

joshu wrote: post #91
JonnieCache wrote: post #86

Earlier quoted context omitted.

>take multiple bad audio signals and combine them into one signal that's better The problem eventually comes down to the fact that "better" is subjective. We're in the murky realm of art here. Should your algorithm keep that fret noise or the squeaking of a vocalist's intake of breath? Are they "noise," or are they part of the performance? >I know nothing about audio processing Not wishing to be rude, but this much i…

Presumably one would get rid of per-device degradation and compression artifacts.

This is the main thing (also tricky)

Re: Show HN: Entire concerts algorithmically "reconstructed" from YouTube videos

#107

Post by transmit101 »

brettwelch wrote: post #34
angusgr wrote: post #3

Wow. Many thoughts arose: - Is this more, less, or equivalently legal (copyright-wise) to just posting the youtube videos on youtube in the first place? It seems like the act of compositing them in this way would be significant, but maybe not? - The normalisation of audio could use some work. SwitchCam seems to do something (the youtube volume on each clip was different for me), but it didn't quite work. - I'd be rea…

Thanks! - I'm no lawyer, but the advice we've received is that we're good on the legal side. - You're on the money re: audio. It's miles better than it was 1 month ago, but we're still not 100% yet. - There is a human curation step (~5% of the process), but that is mostly for removing really crappy videos. Searching/Synching/Sequencing is automatic. - I dunno about next step(!), but i agree the idea is super interest…

> There is a human curation step (~5% of the process), but that is mostly for removing really crappy videos.

Actually, I'd be tempted to make the process 100% automated, and open it up to the general public as soon as possible.

This has the potential to go extremely viral, and occasional "bad" videos could work in favour of this, by introducing an element of humour into the proceedings.

Re: Show HN: Entire concerts algorithmically "reconstructed" from YouTube videos

#108

Post by seats »

brettwelch wrote: post #34
angusgr wrote: post #3

Wow. Many thoughts arose: - Is this more, less, or equivalently legal (copyright-wise) to just posting the youtube videos on youtube in the first place? It seems like the act of compositing them in this way would be significant, but maybe not? - The normalisation of audio could use some work. SwitchCam seems to do something (the youtube volume on each clip was different for me), but it didn't quite work. - I'd be rea…

Thanks! - I'm no lawyer, but the advice we've received is that we're good on the legal side. - You're on the money re: audio. It's miles better than it was 1 month ago, but we're still not 100% yet. - There is a human curation step (~5% of the process), but that is mostly for removing really crappy videos. Searching/Synching/Sequencing is automatic. - I dunno about next step(!), but i agree the idea is super interest…

I wonder how possible it would be both technically and legally to use the audio from the various angles as inputs into an audio processing step where you distill just the true music audio and clean it up. Ideally you'd have one 'cleaned' version of the audio playing and switching views just switches video.

This may be more legally grey than just piping through audio since you are actually producing a derivative work (even if it is mechanically produced), but the net effect would be awesome. You'd end up with better audio than any one person could record, and the more angles you get the higher quality you can make the audio.

Definitely a great idea and very well done for the first cut. You just need some Wilco on there.

Re: Show HN: Entire concerts algorithmically "reconstructed" from YouTube videos

#109

Post by plytheman »

georgieporgie wrote: post #76

This is awesome for two reasons: 1) it's just plain cool and 2) it finally gives a reason to tolerate annoying people who hold up their cell phone cameras during concerts.

It's funny because watching a concert I thought how cool it was that when someone had a camera or phone in my line of sight I could simply switch to another unobstructed view. Then I realized the chances were good that my new view was coming from the very camera I switched views to avoid.

Re: Show HN: Entire concerts algorithmically "reconstructed" from YouTube videos

#110

Post by pbhjpbhj »

brettwelch wrote: post #34
angusgr wrote: post #3

Wow. Many thoughts arose: - Is this more, less, or equivalently legal (copyright-wise) to just posting the youtube videos on youtube in the first place? It seems like the act of compositing them in this way would be significant, but maybe not? - The normalisation of audio could use some work. SwitchCam seems to do something (the youtube volume on each clip was different for me), but it didn't quite work. - I'd be rea…

Thanks! - I'm no lawyer, but the advice we've received is that we're good on the legal side. - You're on the money re: audio. It's miles better than it was 1 month ago, but we're still not 100% yet. - There is a human curation step (~5% of the process), but that is mostly for removing really crappy videos. Searching/Synching/Sequencing is automatic. - I dunno about next step(!), but i agree the idea is super interest…

This certainly looks like a tortuous infringement in the UK (and I'd posit Europe). I didn't get a "only in the US" notice on YouTube though.

I can't see how this is possibly "fair use" - it's the complete work of music and the visual design of the set, choreography and show that is being reproduced in full in a commercial way. Unless the uploaders bought a license with their ticket to reproduce and distribute online and allow derivative works of those reproductions ...

Would be fascinated to read the letter from your IP lawyer justifying this?

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