TinyGPU for Arduino

I recently needed to add SLAM visualization to QGroundControl. The plan: render a map using a simple graphics library, then encode the output via H.265. That’s how I stumbled into writing TinyGPU—and it quickly became my new favorite tool for lightweight embedded graphics. TinyGPU is a lightweight, header-only C++ library for Arduino that handles RGB565 graphics, sprites, and even basic 3D wireframes on small screens. What Makes TinyGPU Different? Most Arduino graphics libraries try to Read more

By pschatzmann, ago

Bringing H.264 Video to the ESP32-S3 with Arduino

Working with the ESP32-S3 has always been about pushing boundaries—especially when it comes to multimedia. While audio on microcontrollers has become fairly common, video is still considered “out of reach” for most embedded setups. That’s what makes the lightweight H.264 support from Espressif Systems so interesting. Native H.264 Support on ESP32-S3 Espressif provides a compact H.264 encoder and decoder component as part of their ecosystem. This is a big deal: H.264 (also known as AVC) Read more

By pschatzmann, ago

ESP32 Arduino: Setting the Stack Size

I am getting old and usually forget the commands that I rarely use. My solution for this: Just ask AI ! Lately I was running into the issue that my ESP32 Arduino test sketches were crashing because there was not enough stack, but this time ChatGPT completely failed me. I finally found the correct answer in the examples provided by Espressif and it is smiple. Just add the following line to your sketch: // Increase Read more

By pschatzmann, ago

IEEE 802.15.4: Audio and Other Uses

IEEE 802.15.4 is a technical standard defining the Physical and Media Access Control layers for Low-Rate Wireless Personal Area Networks. It enables low-power, low-data-rate wireless connectivity for IoT, smart home, and industrial sensors, allowing devices to operate on batteries for years. Here in Europe it uses the Primary Sub-GHz Band: 868.0–868.6 MHz. It is used e.g. by the smart home protocols Thread/Matter and Zigbee. These smart home protocols are suited to control audio, but they are Read more

By pschatzmann, ago

AudioTools: Adding Support for the ESP32‐S3 AI Smart Speaker Development Board

Recently I found the ESP32‐S3 AI Smart Speaker Development Board on Aliexpress for around 15 USD. It has quite some interesting functionality: ES8311 Codec DAC Chip ES7210 Codec ADC Chip with stereo microphones SD Card 6 Neopixel Multicolor LEDs A PCF85063A Real Time Clock 3 User Definable Keys GPIO interface camera interface lcd interface This week I got this board in my mailbox and I expected it to be quite easy to be added to Read more

By pschatzmann, ago

Implementing a DLNA Control Point in Arduino

In my last blogs, I was showing how to create DLNA devices. In my final blog about this topic I will demonstrate how to create a DLNA Control Point (=Client) which uses the functionality of these devices. I will demo a simple Control Point for a Media Renderer which will start playing some music: The Arduino Sketch First we define the relevant objects: In the Arduino setup() we start the processing: We just start the Read more

By pschatzmann, ago

Implementing a DLNA Media Server in Arduino

After having demonstrated how to implement a DLNA Media Renderer in the last blog, I show that it is equally simple to define a DLNA media server. Here is the outline of a basic sketch: The logic for setting up and starting a server is basically the same like the one for the Media Renderer just using the DLNAMediaServer class: The key for this scenario however are two callbacks: one for preparing and the other Read more

By pschatzmann, ago

Walking an Entire Arduino SD Card Directory Tree: A Performance Guide

I was searching for the most efficient generic way to process the whole SD directory tree in Arduino: this can be helpful if you want to search for files or if you want to store the whole file system in a tree in RAM. The Standard SD API Way When using the API provided by the SD library, we need to open each file/directory to find it’s children. So to process all files in the Read more

By pschatzmann, ago

Building an Arduino DLNA Network Wireless Speaker

Im my last blog I was describing the DLNA Architecture. So we are ready now to dig into my first Arduino DLNA Sketch. By combining my arduino-dlna with the arduino-audio-tools library it is quite easy to build a Network Audio Renderer that can e.g. be controlled via an Android Application: I can recommend Hi-Fi-Cast that let’s you select the Music Sources and Playback Devices. When running this sketch you should find and entry named __ArduinoMediaRenderer__ Read more

By pschatzmann, ago

DLNA: The Architecture

The major advantage of the DLNA architecture is it’s clear separation of concerns. This split into specialized roles allows developers to create focused, efficient devices that, when combined, form a sophisticated whole-house audio system. The architecture is built around three core components: Media Servers, which store and distribute (e.g. audio) content; Media Renderers, which receive and play that audio; and Control Points, which act as the intelligent conductors, discovering devices and orchestrating playback between them. Read more

By pschatzmann, ago