The WM8960 based boards are quite popular as Audio Modules for the Rasperry Pi and I had one of these laying around. So I had it always on my to-do list to extend my AudioTools library to support this audio chip as well, so that it can be used in Read more…
I was looking for a simple midi file parser library, but I did not find anything that made me happy, so I decided to provide one myself. Here are my design goals: minimal RAM requirements for midi with 1 track incremental writing and parsing of data No external dependencies: compile Read more…
I always planned to support audio with 24bit values in my Arduino Audio Tools library, but I never actually tested the functionality and so far I did not have a clear understanding of how these values would need to be represented. To be prepared I already provided a draft implementation Read more…
I was never quite happy with my old implementation of the AudioEffects class because it was not very intuitive with the required type parameters and I thought it is about time to improve. So I finally managed to provide a proper Stream implementation that works like many other converting Streams, Read more…
So far I have provided some resampling functionality that was working with some integer factors to up- and downsample. After the work on the Pitch Shifting I realized that we can easily resample using a float based step size to achieve any resampling factor and determine the new values with Read more…
So far I never needed to use any of the ESP32 multicore functionality because all the examples are very simple and everything is fitting on a single core. However if you write some more complex scenarios which are e.g. updating a screen, process user input w/o impacting the audio, you Read more…
I had some pitch shifting effect on my to-do list for a long time now and finally managed to provide this in my Arduino Audio Tools Library. Pitch shifting is the functionality to change the pitch of an input signal w/o changing the length. If you use a higher pitch Read more…
MBROLA is a speech synthesizer based on the concatenation of diphones. It takes a list of phonemes as input, together with prosodic information (duration of phonemes and a piecewise linear description of pitch), and produces speech samples on 16 bits (linear), at the sampling frequency of the diphone database. Today Read more…
It was quite a challenge to convert eSpeak NG to an Arduino Library. In the meantime I managed to publish a first round of error corrections. The eSpeak NG is a compact open source software text-to-speech synthesizer for Linux, Windows, Android and other operating systems. It supports more than 100 Read more…
