BREAKING: Re-port MIDI, faster and lower memory, ESP32#790
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earlephilhower merged 3 commits intomasterfrom Oct 21, 2025
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BREAKING: Re-port MIDI, faster and lower memory, ESP32#790earlephilhower merged 3 commits intomasterfrom
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* Pull untouched upstream TinySoundFont Start from the upstream TinySoundFont by @schellingb at https://github.com/schellingb/TinySoundFont and rearchitect the MIDI processing. * Convert to PROGMEM-based SoundFont structures. This makes it much faster to access the SoundFont and also removes all the static RAM usage. The samples, the regions, the instruments are all now in ROM. Only the dynamic voices and related info takes up RAM. No caching. * (Re)convert to fixed point math. TSF upstream is built for systems with real floating point units (and produces great sound with it!), but processors like the Pico, ESP8266, and several models of ESP32 don't have one so emulate FP in *extremely* slow SW. Use fixed point (integer) represntations for the inner loop and wherever possible to avoid `float` math. For processors like the Pico 2 or original ESP32 with hardware FPUs this still increases performance since integer is still much faster. * Redo the example and add default SF2s Rewrite the 2 MIDI examples to use PROGMEM for both SF2 and MID file. It simplifies life for the casual user and me. * Breaking change The MIDI object now has a `midi::SetSoundFont(tsf *)` instead of a `midi::SetSoundfont(AudioFileSource *)`. It no longer supports reading SF2 from LittleFS or SD.
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Start from the upstream TinySoundFont by @schellingb at https://github.com/schellingb/TinySoundFont and rearchitect the MIDI processing.
This makes it much faster to access the SoundFont and also removes all the static RAM usage. The samples, the regions, the instruments are all now in ROM. Only the dynamic voices and related info takes up RAM. No caching.
TSF upstream is built for systems with real floating point units (and produces great sound with it!), but processors like the Pico, ESP8266, and several models of ESP32 don't have one so emulate FP in extremely slow SW. Use fixed point (integer) represntations for the inner loop and wherever possible to avoid
floatmath.For processors like the Pico 2 or original ESP32 with hardware FPUs this still increases performance since integer is still much faster.
The new TSF doesn't hit the compiler bug the earlier version did, so now Xtensa-based ESP32 boards can run MIDI
Rewrite the 2 MIDI examples to use PROGMEM for both SF2 and MID file. It simplifies life for the casual user and me.
The MIDI object now has a
midi::SetSoundFont(tsf *)instead of amidi::SetSoundfont(AudioFileSource *). It no longer supports reading SF2 from LittleFS or SD.