Real-Time Music Visualization on the iPhone GPU

#1

Post by birslip » Wed, May 31, 2017, 11:14 AM UTC

Real-Time Music Visualization on the iPhone GPU
deezer.io

Re: Real-Time Music Visualization on the iPhone GPU

#2

Post by mpalmer » Thu, Jun 01, 2017, 3:52 AM UTC

This looks interesting but it's pretty hard to judge the quality of real time audio visualization with no audio.

Re: Real-Time Music Visualization on the iPhone GPU

#3

Post by bottled_poe » Thu, Jun 01, 2017, 6:01 AM UTC

mpalmer wrote: post #2

This looks interesting but it's pretty hard to judge the quality of real time audio visualization with no audio.

I wrote a very similar prototype a while ago. Here's a video - https://www.youtube.com/watch?v=oYZEDSzX7MU&feature=youtu.be

I didn't realise at the time, but the X axis is not in logarithmic scale, so most of the audible frequencies are bunched on the left hand side.

Re: Real-Time Music Visualization on the iPhone GPU

#4

Post by taylodl » Thu, Jun 01, 2017, 10:33 AM UTC

I'd be interested in seeing the power load of these visualizations - are they a battery drainer?

Re: Real-Time Music Visualization on the iPhone GPU

#5

Post by rlods » Thu, Jun 01, 2017, 11:17 AM UTC

mpalmer wrote: post #2

This looks interesting but it's pretty hard to judge the quality of real time audio visualization with no audio.

you're right, thank you for the feedback, we'll try to add video samples with royalty free audio content.

Re: Real-Time Music Visualization on the iPhone GPU

#6

Post by stiGGG » Thu, Jun 01, 2017, 11:49 AM UTC

bottled_poe wrote: post #3

mpalmer wrote: post #2

This looks interesting but it's pretty hard to judge the quality of real time audio visualization with no audio.

I wrote a very similar prototype a while ago. Here's a video - https://www.youtube.com/watch?v=oYZEDSzX7MU&feature=youtu.be I didn't realise at the time, but the X axis is not in logarithmic scale, so most of the audible frequencies are bunched on the left hand side.

Nice, do you share the code?

Re: Real-Time Music Visualization on the iPhone GPU

#7

Post by rocky1138 » Thu, Jun 01, 2017, 12:06 PM UTC

At first I was thinking "this isn't a big deal, Atari Jaguar CD did this back in 1995 on way less hardware," but then I realised it was a hackathon project and now I'm really impressed at how far they got in that short frame of time!

Re: Real-Time Music Visualization on the iPhone GPU

#8

Post by birslip » Thu, Jun 01, 2017, 12:11 PM UTC

taylodl wrote: post #4

I'd be interested in seeing the power load of these visualizations - are they a battery drainer?

There is definitely an impact on the battery. The FFT part is well optimised (thanks to the Accelerate framework). What is costly is mainly the shader... and it really depends on the shader. A very simple shader is usually less than 5% of the GPU usage (according the Xcode Instruments, and on a recent iPhone). However if you do a lot in your shader it's going to be much more costly.