JS_Inflator_to_VST2_VST3

JS Inflator, the copy of Sonox Inflator, in vstsdk

Now comes in two GUIs. The new GUI is made by Twarch.

How to use

1. Windows

Unzip Win.zip from latest release and copy to "C:\Program Files\Common Files\VST3".

2. MacOS(Intel tested, Apple Silicon not tested).

Unzip MacOS.zip from latest release and copy vst3 to "/Library/Audio/Plug-Ins/VST3" and component to "/Library/Audio/Plug-Ins/Components".

If it doesn't go well, configure security options in console as

sudo xattr -r -d com.apple.quarantine /Library/Audio/Plug-Ins/VST3/InflatorPackage.vst3  
sudo xattr -r -d com.apple.quarantine /Library/Audio/Plug-Ins/Components/InflatorPackage.component

sudo codesign --force --sign - /Library/Audio/Plug-Ins/VST3/InflatorPackage.vst3  
sudo codesign --force --sign - /Library/Audio/Plug-Ins/Components/InflatorPackage.component  

tested by @jonasborneland here

Linux not compatible.
This is my first attempt with VSTSDK & VSTGUI.
Some codes might be inefficent...

Licensing

Q: I would like to share the source code of my VST 3 plug-in/host on GitHub or other such platform.

• You can choose the GPLv3 license and feel free to share your plug-ins/host's source code including or referencing the VST 3 SDK's sources on GitHub.
• You are allowed to provide a binary form of your plug-ins/host too, provided that you provide its source code as GPLv3 too.
• Note that you have to follow the Steinberg VST usage guidelines.

https://steinbergmedia.github.io/vst3_dev_portal/pages/FAQ/Licensing.html

VSTSDK 3.7.7 used
VSTGUI 4.12 used

Built as VST3, but compatible to VST2, too.

Version logs

v1.0.0: intial try.
v1.1.0: VuPPM meter change(mono -> stereo, continuous to discrete), but not complete!
v1.2.0: VuPPM meter corrected!
v1.2.1: Channel configuration corrected. probably a bug fix for crashing sometimes.
v1.3.0: Curve knob fixed!!! and 32FP dither by airwindows.
v1.4.0: Oversampling up to x8 now works! DPC works.
v1.5.0: Band Split added.
v1.5.1: macOS build added. Intel x86 & Apple silicon tested.
v1.6.0rc: FX meter(Effect Meter) is added. Original GUI is now on high definition.
v1.6.0rc1: Linear phase Oversampling is now added.
v1.6.0: Linear knob mode is now specified, and GUI size flinching fixed.
v1.7.0.beta + beta 2

1. AUv2 build added. VSTSDK update to 3.7.9. Xcode 15.2, OSX 14.2 build.
2. Changed oversampling method from whole buff resample to each sample resample, for less crashes.
3. hiir min-phase resampler is no longer used, and implememted my own FIR resampler with SSE2 optimization.
4. Fir filter is now hardwired.
5. Bypass latency compensated.

Now up to date with latest RC Inflator form ReaTeam/JSFX repository.

What I've learned

• Volumefader

For someone like me, wondering how to use volume fader;
Use a RangeParameter!
param as normalized parameter[0.0, 1.0],
dB as Plain value,
gain as multiplier of each samples.
For normParam to gain, check ~process.cpp

ex)

param	dB	gain
0.0	-12	0.25
0.5	0	1
1.0	+12	4

param	dB	gain
0.0	-12	0.25
0.5	-6	0.5
1.0	0	1

• Resampling

Generally, the process goes as:

1. doubling samples
2. LP Filtering
3. ProcessAudio
4. LP Filtering
5. reducing samples

Filter choice is most critical, I think.
HIIR code used Polyphase Filter, which is minimun phase filter.
Has some letency, has some phase issue, but both very low.

Compared to 31-tap filter, polyphase has more flat frequency and phase response.

Meaning, HIIR is better at anti-alising.

• Linear Phase
  HIIR resampling is Min-phase resampler, meaning phase distortion at high freqs.
  For more natural high frequency hearing I Implemented r8brain-free-src designed by Aleksey Vaneev of Voxengo.
  Had some time with it trying understand how FIR works. I still don't know yet but it works.
  About weird choices for x4 and x8 - these resamplers have asynchronous latencies so downsampling starts little before upsampling starts.
  To fix it, I just changed Transition band for x4 and 24-bit for x8.
  Now it is free of Phase issuses.

• Comparisons
  1x

2x Min-phase

2x Lin-phase

4x Min-phase

4x Lin-phase

8x Min-phase

8x Lin-phase

• Latency Reporting

Naive implementaiton could use 'sendTextMessage' and 'receiveText' pair.

• Knob Modes

Specifying knob modes at 'createView' in 'controller.cpp' makes knobs work in selected mode.

setKnobMode(Steinberg::Vst::KnobModes::kLinearMode);

https://github.com/Kiriki-liszt/JS_Inflator_to_VST2_VST3/blob/v1.6.0/source/InflatorPackagecontroller.cpp#L339

references

1. RC Inflator
   https://forum.cockos.com/showthread.php?t=256286
   https://github.com/ReaTeam/JSFX/tree/master/Distortion

2. HIIR resampling codes by 'Laurent De Soras'.
   http://ldesoras.free.fr/index.html

3. r8brain-free-src - Sample rate converter designed by Aleksey Vaneev of Voxengo
   https://github.com/avaneev/r8brain-free-src
   Modified for my need: Fractional resampling, Interpolation parts are deleted.

Todo

• Preset save & import menu bar.
• malloc/realloc/free to new/delete change. -> stick with it.
• Oversampling options : Linear phase, Balanced.
• GUI : resizing, and HDDPI.
• GUI : double click to enter value.
• soft bypass latency.