coderofsalvation

Unix DSP processors (UDSP's)

Let's face it, non-realtime audio is as important as realtime audio.
UDSP's are a great offline alternative to realtime plugins, which allow for polyglot-scriptable synth & fx-chains.

crossplatform example UD

$ ./myudsp[.exe] [-o out.wav] [-n 60] [in1.wav in2.wav ..] # on unix/mac/linux

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#!/bin/sh 
# usage: 
#   1. put podi project;s in     /home/foo/projectname
#   2. to disable podboot create /home/foo/projectname/podi.stop
#   3. install service using './startpods install'
start(){
  apps="$(find /home/*/*/podi)"
  for app in $apps; do 
    test -f $app".noboot" && continue
    user=$(echo $app | awk -F'/' '{ print $3 }')

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// problem: it's bad   
  if( treshold > 0.0f ){   
        float avg = srcL + srcR;        
        if( avg > peak ) peak = avg;    
        buffer[i]   = (mp_sint32)( tanh(srcL*1.2) * 1.31 * max); // compand once
        buffer[i+1] = (mp_sint32)( tanh(srcR*1.2) * 1.31 * max); // compand once
        if( ZEROCROSSING(srcL+srcR,lastL) ){
          for( ; offset <= i; offset+=2 ){
            float L = (float)buffer[offset]*(1.0/max);
            float R = (float)buffer[offset+1]*(1.0/max);

coderofsalvation

#!/bin/bash
# the following mixes 2 FFT-expressions into a dry (FFT) signal
set -e
in=/tmp/somefile.wav
out="$in.ffmpeg.wav"
winsize=1024
fft_a_r="real='0'"
fft_a_i="imag='tanh(re / 8) * lt(b,4)"                     # bins 0-4
fft_b_r="real='0'"
fft_b_i="imag='tanh(re * 1.8) * gt(b,150) * lt(b,512)'"    # bins 150-512

coderofsalvation

#!/bin/bash
# usage:
#   * put this script in a folder (`./renderall` e.g.)
#   * chmod 755 renderall
#   * convert carboard camera pictures to same folder using this tool: https://github.com/AbosaSzakal/CarboardCamera-Converter
#   * run ./renderall
#   * voila..mp4 files are now in directory /out
fps=25
test -d out && rm -rf out
mkdir out

coderofsalvation

tiny servers: the serverpark killers

auto-suspend-wakeup webservices

stop wasting cpu/mem-resources on idling services:

#!/bin/sh
while sleep 1s; do
 set +e

coderofsalvation

#!/bin/sh
# usage:
#   ./myscript.sh foo bar
#   handler called: foo bar
#   i am foo

call(){ type on_$1 1>/dev/null 2>/dev/null && on_$1 "$@" || "$@"; }

on_foo(){
  echo before handler called: "$@"

coderofsalvation

#!/bin/sh
# usage: ./equi2lovr.sh equi.png
mkdir env 2>/dev/null          
ffmpeg -i $1 -vf "v360=input=equirect:output=c6x1" -y -vframes 1 $1.map.jpg
i=0
for face in px nx py ny pz nz; do 
  ffmpeg -i $1.map.jpg -filter_complex '[0:v] crop=(iw/6):ih:((iw/6)*'$i'):0,split=10[m][m0][m1][m2][m3][m4][m5][m6][m7][m8]' \
    -map '[m]' -s 1024x1024 env/$face.png   \
    -map '[m0]' -s 256x256 env/m0_$face.png \
    -map '[m1]' -s 128x128 env/m1_$face.png \

coderofsalvation

Useful cheap 3D animation tricks

water / fluids

• create a rotating plane
• create material with low roughness and high metallic
• assign a heightmap to the normals
• adjust the uv coordinates so that the heightmap is very zoomed in

coderofsalvation

Useful Lua Patterns/Functions

NOTE: for JS patterns see my JS patterns-page

Simple javascript-like template function

-- print( tpl("${name} is ${value}", {name = "foo", value = "bar"}) )
-- "foo is bar"
function tpl(s,tab)