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Minimy

This is a fork of Ken-Mycroft's code at: https://github.com/ken-mycroft/minimy

Overview

From Ken Smith - the original author:

"The goal of this project is to provide a run-time environment which facilitates the development of voice enabled applications. These voice enabled applications take the form of a 'skill' and are simply python programs which may do normal python things as well as call speak() and listen() and get called asynchronously when an utterance is matched to an intent the skill has previously registered."

From Mike Mac - author of this fork:

This code enables a device to play music by voice.

I worked with Mycroft since 2019, and was able to get a prototype music skill, based on mpc/mpd, working. But the company went bankrupt in 2023, so had to move on. :(( Thanks for all the hard work the Mycroft employees and contributors did to get us this far.

OVOS is a fork of Mycroft and Neon is another layer on top. I tried OVOS but was not able to get my music skill working after a couple weeks. I still haven't given up on it - no doubt it will only get better and easier to install.

Then I found Minimy, and was able to get it running in a few hours. Apparently, it was a project that hoped to save Mycroft from the fire but wasn't well received. Thankfully, Ken Smith put it on github, it was forked, and here we are. Ken has been a great help in answering my many questions - Thanks Dude! So I continue to try to give back to the community while standing on the shoulders of so many others.

This document describes how to get the solution running, and starts from the very beginning.

Here is a video of a beta version: https://www.youtube.com/watch?v=WRiqg0b-EPI

The build

The environment used to develop the code and write this document is a RasPi 4B with 4 GB of memory, running Ubuntu Desktop 22.04 inside an enclosure that is a retro-looking boombox. Later Raspberry Pi OS (aka Raspbian) versions 10 (buster) and 11 (bullseye) were tested. However, this code and these steps should be relatively portable to any hardware that can run any Linux.

The overall steps to build a Smart Boombox are:

  • Acquire the hardware
  • Flash Linux to a memory device
  • Connect the hardware
  • Install and configure Linux
  • Install and use ovos-tools
  • Test microphone and speakers
  • Install and configure Minimy
  • Start Minimy and use it!

Acquire the hardware

The recommended hardware is a Raspberry Pi (RasPi) 4B with 4 or 8 GB of memory. Yes, they're still hard to get, but not impossible.

A Rasberry Pi 400 is another option. It allows the CPU to be offboard which frees up space onboard to house batteries. The CPUs also run a lot cooler due to the massive heat sink.

Hopefully the RasPi 5 will be out soon and will be more powerful, run cooler, and be easier to procure.

For a microphone, a flat, disk type with a mute/unmute switch for visible privacy is recommended. Don't use a cheap one. It is best to move the microphone away from the speakers and closer to the center of the room.

You can start with just about any speaker(s) with a 3.5mm jack that will plug into the RasPi. I could start writing about DAC HATs and audio quality, but that's outside the scope of this document.

Flash Linux to a memory device

The RasPi boots from a micro-SD card that plugs into its underside. A 32 GB card or larger is recommended. You need to prime the pump and copy a Linux distribution to it.

The following three flavors of two Linux distributions are supported. Note that Raspbian has been renamed to Raspberry Pi OS but in many places the original name is still used.

  • Ubuntu 22.04.2 LTS
    • LTS stands for Long Term Support - Canonical promises to support it for at least five years.
  • Raspbian GNU/Linux 10 (buster)
  • Raspbian GNU/Linux 11 (bullseye)

You will need another computer (ideally running Linux) to copy the Linux image to the memory card.

Prepare on Linux

If you have a Linux box with an SD card port, you can use rpi-imager to copy the Linux image. To do so, perform the following tasks.

  • Put a micro-SD card into an SD adapter.

  • Plug the SD adapter into the card reader.

  • If you don't have it already, install the tool.

    sudo apt-get install -y rpi-imager

  • Run the tool.

    rpi-imager

    You should see a window as shown in the following figure.

  • To flash a Linux image to the card, perform the following steps:

    • Select one of three choices from Operating System.

      • Raspberry Pi OS (32-bit) Debian Bullseye with Desktop
      • Raspberry Pi OS (legacy) => Debian Buster with Desktop
      • Other General Purpose OS => Ubuntu => Desktop 22.04.2 LTS (64-bit)

    • Select the Storage device. You should see just one micro-SD card in the dropdown menu. If you don't see any entry, your SD card has not been recognized.

    • Click Write.

    • If you are challenged for credentials, enter the password of the current user.

You should see a progress indicator as the image is copied to the SD card. It should take around 5 minutes.

Prepare an SD card on Windows

If you only have access to a Windows system Install the Win 32 disk imager from https://sourceforge.net/projects/win32diskimager/

There is now a port of rpi-imager to Windows. See: https://downloads.raspberrypi.org/imager/imager_latest.exe

No further details are provided.

Connect the hardware

For the initial setup, a keyboard, monitor and mouse are needed. You can access the Internet using either Wi-Fi or with an Ethernet cable.

To connect all the computer hardware, perform the following steps:

  • Plug the micro-SD card into the back underside of the RasPi.
  • If you have wired ethernet, plug it in to the RJ-45 connector on the RasPi.
  • Connect the mouse and keyboard to the USB slots.
  • Connect the monitor to the RasPi with an appropriate micro-HDMI cable. The RasPi 4 two micro HDMI ports - only the left one sends output at boot time.
  • If you have a USB drive with music files on it, plug it in to a USB slot.
  • Now that all the other hardware is connected, plug the 5v power supply with a USB-C end into the RasPi 4. An official RasPi power supply is recommended to avoid undervoltage warnings. If you have an inline switch, turn it on.

Install and configure Linux

To install and configure Ubuntu Desktop Linux, perform the following sections.

  • Boot the RasPi
  • Initial Ubuntu Desktop configuration -or- Initial Raspbian Desktop configuration
  • Install the SSH server
  • Start a terminal or SSH session
  • Update and upgrade your system

Boot the RasPi

When you supply power to the RasPi, it should start booting. On the top, back, left side of the RasPi there are two LEDs:

  • The LED to the left should glow solid red. This signifies it has 5V DC power.
  • The LED to the right should flicker green. This signifies that there is communicaiton with the CPU. If there is a red light, but no green one, it's likely the micro-SD card does not have Linux properly installed.
  • You should see a rainbow colored splash screen on the monitor, then the Ubuntu desktop should initialize.

IMPORTANT: Never turn the RasPi off without first shutting Linux down with the halt or similar command. Doing so can damage the operating system and possibly even the RasPi itself.

Initial Ubuntu Desktop configuration

If you are installing Raspbian, skip to the next section.

A welcome screen should open on the monitor. Perform the following steps:

  • On the Welcome window, choose your language and click Continue.
  • On the Keyboard layout window, choose your layout and click Continue.
  • On the Wireless window, if you are not using a hard-wired Ethernet, click Connect and configure a Wi-Fi network. You must know the network SSID and will probably be prompted for a password.
  • On the Where are you? window, choose your time zone.
  • On the Who are you? window, set the following values:
    • Set your name.
    • Set your computer’s name (host name).
    • For a user name and password pi is recommended as it is documented in the reminder of this document.
    • For the last option, Log in automatically is recommended.
    • Click Continue.
  • The install process will take a number of minutes configuring and will reboot the computer.
  • When the system finishes rebooting, an Online Accounts window should appear. Click Skip.
  • Click Next at the Enable Ubuntu Pro window.
  • Choose an option on the Help Improve Ubuntu window and click Next.
  • Click Next at the Privacy window.
  • Click Done at the Ready to go window.

Ubuntu Desktop 22.04 should now be installed

Initial Raspbian Desktop configuration

If you are installing Ubuntu, skip this section.

To install and configure Raspbian, perform the following steps:

  • At the Welcome to the Raspberry Pi Desktop! window => click Next.
  • At the Set Country window - choose your country, language and time zone and click Next.
  • At the Create User window - The user name must be pi.
  • At the Set up screen window - Check the box if you see a black box around the monitor and click Next.
  • At the Select WiFi Network window - choose your network and click Next.
    • At the Enter WiFi Password window, enter the password and click Next.
  • At the Update Software window - click Skip - the upgrade will be done from a terminal session.
  • At the Setup complete window - click Done or Restart.

Setting up the SSH server on Ubuntu

If you are installing Raspbian, skip to the next section.

The secure shell (SSH) server is not installed by default on Ubuntu desktop. Install it so you can access your system remotely. To do so, perform the following steps:

  • Open a terminal session by right-clicking the mouse anywhere on the desktop and choosing Open in Terminal. You should see a console window open.

  • Show the contents of the /etc/os-release file.

    cat /etc/os-release

  • Update and upgrade your system which installs the latest code for all installed packages.

    sudo apt-get update

    sudo apt-get upgrade -y

  • Install the openssh-server package, with the following command. You will be prompted for your password.

    sudo apt-get install -y openssh-server

    [sudo] password for pi:

  • After it installs sshd should be running. Verify with the following command:

    service sshd status

Setting up the SSH server on Raspbian

If you are installing Ubuntu, skip this section.

The secure shell (SSH) server is installed by default on Raspbian, but not running.

To start it now, and enable it at boot time, perform the following steps:

  • Click the red Raspberry icon in the upper left corner, then in the drop-down menu choose Accessories then Terminal.

  • From the terminal session, start the SSH server for the current session.

    systemctl start ssh

  • Set the SSH server to start at boot time.

    systemctl enable ssh

Start a terminal or SSH session

You can continue to work from a terminal session or you can SSH in to your new Linux system. To SSH in, perform the following steps.

  • Get your IP address. You should have either a Wi-Fi (wlan0) or a hard-wired (eth0) connection. To verify, enter the following command.

    ip a 
1: lo:
...
2: eth0:
...
3: wlan0:
...
inet 192.168.1.229

SSH as the user pi, if you want to continue from another system. You can use putty to SSH in from a Windows box, or just use the ssh command from a Linux or macOS console.

IMPORTANT: Do not run as root. Doing so will almost certainly screw up your system. Users other than pi ideally will work as the environment variable $HOME is used in scripts, however, this has never been tested.

Install and use ovos-tools

The ovos-tools repo has been developed to help with the installation, configuration, use and testing of the free and open personal voice assistants.

To install ovos-tools perform the following steps:

  • Install git and vim as they are needed shortly.

    sudo apt-get install -y git vim

  • Make vim the default editor.

    sudo update-alternatives --install /usr/bin/editor editor /usr/bin/vim 100

    update-alternatives: using /usr/bin/vim to provide /usr/bin/editor (editor) in auto mode

  • Allow members of the sudo group to be able to run sudo commands without a password, by adding NOPASSWD: to the line near the bottom of the file.

    sudo visudo

    ...
%sudo   ALL=(ALL:ALL) NOPASSWD: ALL
...

  • Clone the ovos-tools package in the pi home directory with the following commands:

    git clone https://github.com/mike99mac/ovos-tools

    Cloning into 'ovos-tools'...
...
Resolving deltas: 100% (366/366), done.

  • Change to the newly installed directory and run the setup script. It will copy scripts to the directory /usr/local/sbin which is in the default PATH.

    cd ovos-tools

    sudo ./setup.sh

    The ovos-tools repo is now installed.

Further customize

The script install1, in the ovos-tools package you just installed, runs many commands and thus saves typing, time and possible errors.

It performs the following tasks:

  • Installs the mlocate mpc mpd net-tools pandoc python3 python3-pip python3-rpi.gpio python3.10-venv packages
  • Sets vim to a better color scheme and turns off the annoying auto-indent features
  • Adds needed groups to users pi and mpd
  • Copies a .bash_profile to the user's home directory
  • Turns default and vc4 audio off and does not disable monitor overscan in the Linux boot parameters file.
  • Changes a line in the rsyslog configuration file to prevent kernel message floods
  • Copies a systemctl configuration file to mount /var/log/ in a tmpfs which helps prolong the life of the micro-SD card
  • Sets pulseaudio to start as a system service at boot time, and allows anonymous access so audio services work
  • Configures mpd, the music player daemon, which plays most of the sound
  • Turns off bluetooth as Linux makes connecting to it difficult, while most amplifiers make it easy

To run intall1, perform the following steps:

  • Run the install1 script.

    cd

    install1

Test the changes

  • Test your environment with the newly installed lsenv script which reports on many aspects of your Linux system.

    lsenv

The output should show:

  • Processes with minimy in their name are not running.
  • The Music Playing Daemon, mpd is not running.
  • There is one pulseaudio process running, but it does not have --system as a parameter.
  • Useful information such as IP address, the CPU temperature, root file system, CPU and memory usage.
  • None of the file systems frequently written to are mounted as in-memory tmpfs file systems.

Test changes of install1 script

Some of the changes made by install1 will not be realized until boot time. To test this, perform the following steps:

  • Reboot your system

    sudo reboot

  • Restart your SSH session when it comes back up.

  • Run the same script again to see how the environment has changed.

    lsenv

You should see three changes:

  • The Music Playing Daemon, mpd is now running.
  • The one pulseaudio process shows a --system parameter which is vital to audio output working correctly.
  • The /var/log/ directory is now an in-memory tmpfs file system.

Test microphone and speakers

It is important to know your microphone and speakers are working. There are scripts in ovos-tools named testrecord and testplay. They are wrappers around the arecord and aplay commands designed to make it easier to test recording audio to a file and playing it back on the speaker(s).

  • To test your microphone and speakers, issue the following command then speak for up to five seconds.

    testrecord

    Testing your microphone for 5 seconds - SAY SOMETHING!
INFO: running command: arecord -r 44100  -f S24_LE -d 5 /tmp/test-mic.wav
Recording WAVE '/tmp/test-mic.wav' : Signed 24 bit Little Endian, Rate 44100 Hz, Mono
...

You should hear your words played back to you. If you do not, you must debug the issues - there's no sense in going forward without a microphone and speaker(s).

At this point your system should have a solid sound and microphone stack running, especially mpd and pulseaudio, and all software necessary for the installation of Minimy.

Install and configure Minimy

If you want to install OVOS instead of Minimy, go here: https://github.com/mike99mac/mycroft-tools/tree/master/ovos

In this section you will perform the following steps:

  • Download and copy Minimy
  • Install Minimy
  • Configure Minimy
  • Get a Google API key

Download and copy Minimy

It is recommended that you make a second copy of Minimy after you download it. This way, if you make some changes to the running code, you'll have a reference copy. Also the copy of the code that you run should not have a .git/ directory, thus removing any connection to github.

The new directory must be named minimy, removing the -mike99mac suffix, as scripts are coded that way.

To download and copy Minimy, perform the following steps:

  • Change to your home directory and clone the repo from github.

    cd

    git clone https://github.com/mike99mac/minimy-mike99mac

  • Copy the directory recursively from minimy-mike99mac to minimy.

    cp -a minimy-mike99mac minimy

  • Remove the .git directory from the copy.

    cd minimy

    rm -fr .git

    Now the code will run and you can work in minimy and keep minimy-mike99mac as a reference copy.

Install Minimy

  • Run the following script to install Minimy and direct stdout and stderr to a file. TAKE A BREAK? This step can take up to 15 minutes.

    ./install/linux_install.sh

    It is recommended that you review the output file, checking for warnings or errors.

  • Open a virtual environment.

    source $HOME/minimy/venv_ngv/bin/activate

    You should see a new (venv_ngv) prefix on the command line.

Configure Minimy

The system can use local or remote services for speech to text (STT), text to speech (TTS) and intent matching. Intent matching is accomplished using natutal language processing (NLP) based on the CMU link parser using a simpe enumerated approach referred to as shallow parsing.

As a result you will be asked during configuration if you would like to use remote or local STT, TTS and NLP. Unless you have a good reason, for now you should always select local mode (remote=n) for NLP.

Remote TTS using polly requires an Amazon ID and key. If you prefer to not use polly for remote TTS you may choose mimic2 from Mycroft which is a free remote TTS alternative. You could also select local only TTS in which case mimic3 should work fine.

By deault the system will fallback to local mode if a remote service fails. This will happen automatically and result in a slower overall response. If the internet is going to be out often you should probably just select local mode. The differences are that remote STT is more accurate and remote TTS sounds better. Both are slower but only slightly when given a reasonable internet connection. Devices with decent connectivity should use remote for both.

You will also be asked for operating environment. Currently the options are (p) for piOS, (l) for Ubuntu or (m) for the Mycroft MarkII.

Three syllable or more wake words are best. Words like 'computer' or words with distinct sounds like 'expression' (the 'x') or 'kamakazi' (two hard 'k's) will always work better than words like 'hey' or 'Joe'.

You will also be asked to provide an input device index. If you do not know what this means enter the value 0. If you would like to see your options you can run 'python framework/tests/list_input_devices.py'. Remember, if you do not source your virtual environment first, things will not go well for you.

The SVA_BASE_DIR and PYTHONPATH environment variables should set properly in your ~/.bash_profile.

  • Run the following configuration script. In this example all defaults were accepted by pressing Enter for each question (except the log level was set to debug). At the end y was entered to save the changes.

    (venv_ngv) $ ./mmconfig.py sa

    Advanced Options Selected sa
... all defaults taken except debug level ...
Save Changes?y
Configuration Updated
  Advanced
    ('CrappyAEC', 'n')
    ('InputDeviceId', '0')
    ('InputLevelControlName', 'Mic')
    ('LogLevel', 'd')
    ('NLP', {'UseRemote': 'n'})
    ('OutputDeviceName', '')
    ('OutputLevelControlName', 'Speaker')
    ('Platform', 'ubuntu')
    ('STT', {'UseRemote': 'y'})
    ('TTS', {'Local': 'm', 'Remote': 'p', 'UseRemote': 'y'})
  Basic
    ('AWSId', '')
    ('AWSKey', '')
    ('BaseDir', '/home/pi/minimy')
    ('GoogleApiKeyPath', 'install/my_google_key.json')
    ('Version', '1.0.4')
    ('WakeWords', ['hey computer', 'computer'])

Run Minimy

The scripts startminimy and stopminimy are used to start and stop processes. Each skill and service run as process and use the message bus or file system to synchronize. Their output is written to the logs/ directory under the main install directory.

The system relies on the environment variables PYTHONPATH, SVA_BASE_DIR and GOOGLE_APPLICATION_CREDENTIALS which are set in startminimy with this code:

...
export PYTHONPATH="$HOME/minimy:$HOME/minimy/venv_ngv/lib/python3.10/site-packages"
export SVA_BASE_DIR="$HOME/minimy"
export GOOGLE_APPLICATION_CREDENTIALS="$HOME/minimy/install/my-google-key.json"
...

  • Start Minimy, ensuring it is run from the base directory, as follows.

    startminimy

  • Run lsenv again to see how your environment has changed.

    lsenv

    Status of minimy: -) WARNING: minimy is not running as a service ... checking for processes ... Minimy user skills: connectivity email example1 help mpc timedate weather wiki System skills: buttons intent media_player mic skill_alarm skill_fallback skill_media skill_volume stt tts

    Status of mpd: -) mpd is running as a service: Active: active (running) since Sat 2023-06-10 10:13:24 EDT; 2h 3min ago

    Status of pulseaudio: -) pulseaudio is running as a service: Active: active (running) since Sat 2023-06-10 10:13:22 EDT; 2h 3min ago pulseaudio processes: pulse 850 1 2 10:13 ? 00:03:35 /usr/bin/pulseaudio --system --disallow-exit --disallow-module-loading --disable-shm --exit-idle-time=-1

       IP address : 192.168.1.148

    CPU temperature : 72C / 161F Root fs usage : 18% CPU usage : 58% Memory usage : total used free shared buff/cache available Mem: 3.7Gi 1.8Gi 224Mi 44Mi 1.7Gi 1.7Gi Swap: 1.0Gi 4.0Mi 1.0Gi tmpfs filesystem? /var/log Linux logs : yes /home/pi/minimy/logs Minimy logs : yes /home/pi/minimy/tmp Minimy temp dir : yes

You should see two changes:

  • Minimy is now running - the output showing user and system skill processes.
  • The two minimy file systems frequently written to are now mounted over in-memory tmpfs's.

The buttons process

The smart boombox model with the RasPi on-board has three pushbuttons on the front panel to allow quick access to previous track, pause/resume, and next track operations. If you hold the middle button for more that two seconds, it does a stop function, which also clears the music queue. A new buttons system skill traps button presses and sends corresponding messages to the bus.

If you want to add buttons to your enclosure, attach them to the following GPIO pins:

+-----+--------+-------------------------------+
| Pin | Label  | Description                   |
|-----|--------|-------------------------------|
| 9   | GND    | Ground common to all buttons  |
| 11  | GPIO17 | Previous track                |
| 13  | GPIO27 | Pause/resume                  |
| 15  | GPIO22 | Next track                    |
+-----+--------+-------------------------------+

Here is a source of purchasing pushbuttons: https://www.amazon.com/dp/B09C8C53DM

Debugging

Maybe everything will work perfectly the first time, and you won't have to debug (but we know how that goes :))

Following are some debugging resources.

  • Many, many debug statements have been added to the code. In most classes, every function has at least one log statement when in debug mode with the class, the function, and the parameters passed.

  • Log files are in $HOME/minimy/logs.

    • Show the log files.

      cd $HOME/minimy/logs
ls

      intent.log media_player.log skills.log stt.log tts.log

    • When Minimy is running, you can watch all the log files get populated in real time with the following command:

      tail -f *

  • There is an HTML file with JavaScript code that displays the message bus in real time. If you do not have a Web server running, you must view it from the local host.

    • Start a browser on the box you're installing on and point it to file:///home/pi/minimy/display/sysmon.html
    • You should see all messages written to the message bus and the associated data.

  • The sortlogs script - merges and sorts all the log files by timestamp and saves them to /tmp. The merged output is often easier to peruse than the individual files.

  • The stopminimy script calls sortlogs so every time you stop Minimy, there is a new log file copied to /tmp/ which persists across the starting and stopping of Minimy, unlike $HOME/minimy/tmp/.

    $ stopminimy
...
killing process: pi        952424       1 10 16:25 pts/3    00:00:11 python3 framework/services/input/buttons.py ...
killing process: pi        952425       1  7 16:25 pts/3    00:00:08 python3 framework/services/input/mic.py ...
sorted logs saved to: /tmp/logs-2023-07-01-16:27:34

  • There's a RELEASE-NOTES.md and TODO.md that show a history of the project and a wish list of things to do.

  • Google searches, of course ...

  • You can email me at mike99mac at gmail.com - can't promise anything, but I will try.

Reference

These reference sections follow:

  • Vocabulary and examples
  • Other Documentation

Vocabulary and examples

In the samples that follow, (words) in parenthesis are the actual words spoken, while {words} in curly brackets become variables populated with the actual words spoken. When (multiple|words|) are separated by vertical bars, any of those can be spoken, and a trailing vertical bar means that word can be omitted.

Connectivity skill

Following is the Connectivity skill vocabulary.

Following are examples of Connectivity skill requests:

Email skill

Following is the Email skill vocabulary.

(compose|create|new|start) email
send email

Following are examples of Email skill requests:

  • start email
  • ... dialog continues ...
  • send email

Example1 skill

Following is the Example1 skill vocabulary.

(run|test|execute) example one

Following are examples of Example1 skill requests:

  • run exmple one

Help skill

Following is the Help skill vocabulary.

Following are examples of Help skill requests:

MPC skill

The MPC skill can:

  • Play from your music library
  • Play Internet radio stations
  • Play Internet music
  • Play NPR news
  • Create, delete, manage and play playlists
  • Perform basic player operations

Following are the vocabularies for the MPC skill:

  • Music library vocabulary:

    play (track|song|title|) {track} by (artist|band|) {artist}
play (album|record) {album} by (artist|band) {artist}
play (any|all|my|random|some|) music 
play (playlist) {playlist}
play (genre|johnra) {genre}

  • Internet radio vocabulary:

    play (the|) radio
play music (on the|on my|) radio
play genre {genre} (on the|on my|) radio
play station {station} (on the|on my|) radio
play (the|) (radio|) station {station}
play (the|) radio (from|from country|from the country) {country}
play (the|) radio (spoken|) (in|in language|in the language) {language}
play (another|a different|next) (radio|) station
(different|next) (radio|) station

  • Internet music vocabulary:

    play (track|artist|album|) {music} (from|on) (the|) internet

  • NPR News vocabulary:

    play (NPR|the|) news

  • Playlist vocabulary:

    (create|make) playlist {playlist}
(delete|remove) playlist {playlist}
add (track|song|title) {track} to playlist {playlist}
add (album|record) {album} to playlist {playlist}
(remove|delete) (track|song|title) {track} from playlist {playlist}
list (my|) playlists
what playlists (do i have|are there)
what are (my|the) playlists

  • Basic player commands vocabulary:

    previous (song|station|title|track|)
next (song|station|title|track|)
pause                               # stop music but maintain queue
resume
stop                                # stop music and clear queue

increase volume
decrease volume

Following are examples of MPC skill's requests:

  • Play track one and only by artist adele.
  • Play album abbey road
  • Play genre blues on the radio
  • Play language german on the radio
  • Play track stressed out by artist twenty on pilots
  • Play npr news
  • Play artist the chainsmokers from the Internet

Timedate skill

Following is the Timedate skill vocabulary:

what time (is it|)
what (is|) (today's|) date
what day (of the week|) (is it|)

Following are examples of skill's requests:

  • What time is it?
  • What is today's date
  • What day of the week is it

Weather skill

Following is the Weather skill vocabulary:

(what's|what is) (the|) weather (forecast|)

Following are examples of Weather skill requests:

  • What's the weather?

Wiki skill

The Wiki skill is a fallback skill. As such it does not have a vocabulary

More documentation

There is more documentation, by the original author Ken Smith, here: https://github.com/ken-mycroft/minimy/tree/main/doc

Local Speech to Text

In late 2024 there was work done on running Speech to Text (STT) locally.

If it takes more than three or four seconds to translate your speech, the personal voice assistant seems quite slow. People are used to responses in less than two seconds, ideally less than a second.

Internet services, such as Google offer STT transcription. In addition to custom hardware, such as tensor processors, audio streams are split into smaller segments and processed in parallel, significantly speeding up transcription.

However, this greatly reduces people's privacy. Ideally the STT can be performed locally and nothing goes out on the Ineternet.

Three SoC platforms are tested for speed:

  • Raspberry Pi 4
  • Raspberry Pi 5
  • Nvidia Jetson GPU

The Raspberry Pi's are less than $100. The Nvidia GPU is about $500.

Preparing the Nvidia GPU

Getting the Nvidia Jetson Orin Nano working took quite a bit of time.

It does not appear possible to boot conventional ARM Linux images on it. Rather, the Nvidia JetPack has to be used. I tried Jetpack 6 which was the latest, but it would not boot. I downgraded and installed it as follows:

Now the box finally booted. However, it was running Ubuntu 20.04 which was 4.5 years old at the time. The Python version was 3.8 which was too old for some packages. The solution was to upgrade the firmware with the following command:

sudo apt-get install nvidia-l4t-jetson-orin-nano-qspi-updater

With the firmware upgraded, it was finally able to boot Jetpack 6. Here are the steps to upgrade to Jetpack 6:

Now Ubuntu 22.04 is running which has a Python version of 3.10.12. However, more care and feeding will be needed to utilize the GPUs.

Creating virtual environments

Python virtual environments (venvs) are highly recommended for testing and to maintain the integrity of your development environment.

A script to create a venv for the Raspberry Pis is here: https://github.com/mike99mac/minimy-mike99mac/blob/main/mksttvenv It creates the venv stt_venv in your home directory. It must be enabled with:

cd
. stt_env/bin/activate

You should see a prefix of (stt_venv) on your command prompt (PS1).

The file jfk.wav, hard-coded in the above code, is an 11 second audio clip of John F Kennedy's famous words at his inaguration: "And so my fellow Americans ask not what your country can do for you ask what you can do for your country."

The first two tests were the Raspberry Pi 4 and the Nvidia GPU. The GPU was only 7 or 8 percent faster. It seems the 1024 GPU cores were not being utilized.

This code tests whether the GPU cores are working:

#!/usr/bin/env python3
import torch
print("CUDA available:", torch.cuda.is_available())
if torch.cuda.is_available():
    print("CUDA device:", torch.cuda.get_device_name(0))

Many, many different ways of getting the GPUs enabled were tried. Every time the results were:

CUDA available: False

Finally a script was written to create a venv for the Nvidia GPU here: https://github.com/mike99mac/minimy-mike99mac/blob/main/mksttvenvgpu

This script downloads wheel files for Python torch, torchaudio and torchvision, then installs them in the venv. Finally the output was good:

CUDA available: True
CUDA device: Orin

Getting STT running locally

The code used to test the performance is below. I believe tracking the elapsed time of just the transcribe() function is correct. Here's the code:

$ cat bldwhisper.py
#!/usr/bin/env python3
import argparse
import numpy as np
import pyaudio
import time
import whisper
import wave

class WhisperTranscriber:
  """ Build whisper for local STT using the base.en model """

  def __init__(self):
    self.model = "base.en"                 # tiny.en and small.en are also possible
    self.parser = argparse.ArgumentParser(description="Transcribe audio using Whisper.")
    self.parser.add_argument("filename", type=str, help="Path to the audio file")
    self.args = self.parser.parse_args()

  def load_model(self):
    print("Loading Whisper model ...")
    self.model = whisper.load_model(self.model)  # Load the quantized model

  def transcribe_audio(self, filename):
    print("transcribe_audio(): loading audio ...")
    audio = whisper.load_audio(filename)
    print("transcribe_audio(): pad or trim audio ...")
    audio = whisper.pad_or_trim(audio)
    print("transcribe_audio(): transcribing audio ...")
    start_time = time.time()
    result = self.model.transcribe(audio, fp16=False)  # transcribe to text
    end_time = time.time()
    et = end_time - start_time
    print("Transcription: ", result["text"])
    print(f"Elapsed time: {et}")

if __name__ == "__main__":

  # Create an instance of the WhisperTranscriber class
  transcriber = WhisperTranscriber()                      # create a singleton
  transcriber.load_model()                                # load the model
  transcriber.transcribe_audio(transcriber.args.filename) # transcribe a file

The results

Here are the performance times on the three "boxes":

Platform Memory Python tiny.en base.en small.en
Raspberry Pi 4 4 GB 3.11 8.0s 15.1s 75.0s
Raspberry Pi 5 8 GB 3.11 6.5s 6.7s 21.3s
Nvidia Jetson Orin Nano 8 GB 3.10 1.3s 0.9s 1.7s

The best option seems to be the base.en model running on the Nvidia GPU.

Here's a picture of the three boxes. The Raspberry Pi 4 on the left and Pi 5 on the right are both in boomboxes for superior sound. The GPU is to the right of the keyboard. A boombox carcass for it is coming soon...