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~ focus

$ whoami
William Ho — Computer Engineering @ Cal Poly San Luis Obispo

$ cat focus.txt
I build firmware that makes hardware play hi-res sound —
multi-codec Bluetooth audio, real-time DSP, and the occasional
reverse-engineered codec running bare-metal on an ESP32.

$ ls ~/interests
hardware/software boundary   low-latency wireless audio   embedded DSP

• Now — multi-codec A2DP firmware for the ESP32 family: LDAC, aptX / HD / LL, LHDC V5, AAC, Opus, LC3plus, SBC
• Depth — real-time DSP: equalizers, bass boost, level meters, clock sync, packet-loss concealment
• Reach — Android companion apps (Kotlin / Flutter) that drive it all over BLE — EQ, codec selection, OTA, live visualization
• Learning — ESP-IDF internals, FreeRTOS scheduling, and squeezing hi-res codecs onto internal SRAM

> reverse-engineering

LHDC-V5-Decoder

I reverse-engineered the proprietary LHDC V5 hi-res Bluetooth codec — digging through binaries until it became a working decoder that runs on an ESP32, wired straight into the A2DP audio pipeline. A microcontroller playing hi-res audio nobody documented. 🎧

# stack

Languages    C  ·  C++  ·  Kotlin  ·  Dart
Embedded     ESP-IDF  ·  FreeRTOS  ·  Arduino  ·  CMake
Wireless     Bluetooth A2DP / BLE GATT  ·  ESP-NOW
Codecs       LDAC · aptX HD/LL · LHDC V5 · LC3plus · Opus · AAC · SBC
DSP          3-band EQ · Bass Boost · Level Meters · PLC · Clock Sync · Adaptive Buffering
Mobile       Android (Kotlin)  ·  Flutter
Tooling      Git  ·  Android Studio  ·  Logic / Signal Analysis

* featured projects

Project	Stars	What it is
🎚️ ESP32-S31-A2DP-Codecs		Multi-codec A2DP sink on ESP-IDF v6.1 — LDAC, aptX/HD/LL, LHDC V5, Opus, LC3plus, AAC, SBC — all on internal SRAM
🔊 esp32-a2dp-sink-with-LDAC-APTX-AAC		A2DP audio sink with BLE GATT control, DSP, level meters and LDAC
🎵 ESP32-A2DP-SINK-WITH-CODECS-UPDATED		A2DP sink with LDAC, aptX, aptX-HD & AAC codec support
🎼 LHDC-V5-Decoder		Reverse-engineered LHDC V5 decoder, integrated into the ESP32 A2DP pipeline
📱 BDK-AUDIO-APP		Android control app — DSP/EQ, codec selection, LED effects, OTA over BLE
🖥️ NVFLASH		Patched NVFlash supporting RTX 50-series GPU BIOS flashing

· browse all repositories ·

~ activity

🛠️ Most recently pushed to LHDC-V5-Decoder on 2026-07-25
LHDC V5 Decoder For ESP32's A2DP Integration
C

_{· auto-updates via GitHub Actions ·}

@ contact

_{$ echo "building things that make sound 🔊"}