I am currently trying to write a program that will detect a notification sound from an app and press some keys in response. I want it to be able to detect a specific sound from a sound file. This app also has background noise coming from it.
My research has been less than successful in finding an audio recognition software. If worst comes to worst I can also just use something that pulls audio from input and finagle OBS.
Is there a way using python (and not any external software) to play a mp3 file like a microphone input?
For example, I have a mp3 file and with a python script it would play it through my mic so other in a voice room would hear it. As I say it is just an example.
Of course, I have done some research. I found out that I can use a software to create a virtual device and do few things to have the result. But my point is if it is possible without installing software but with some kind of python script?
It is possible but it isn't 100% in python as it requires the installation of other software. (Also from what I know this specific answer only works on Windows, but it should be similar on Linux with PulseAudio instead of VB-Audio Cable, but I'm not a daily Linux user so I don't know.)
First download: https://www.vb-audio.com/Cable/, this will create a "Virtual Audio Cable" where programs can play music to the input device (What looks like a speaker) and it'll pipe it to the output device (What looks like a microphone).
Then run this command in cmd: pip install pygame==2.0.0.dev8 (or py -m pip install pygame==2.0.0.dev8, depending on your installation of python) [Also the reason it's the dev version is that it requires some functions only in sdl2, whereas the main branch uses sdl1)
Then:
>>> from pygame._sdl2 import get_num_audio_devices, get_audio_device_name #Get playback device names
>>> from pygame import mixer #Playing sound
>>> mixer.init() #Initialize the mixer, this will allow the next command to work
>>> [get_audio_device_name(x, 0).decode() for x in range(get_num_audio_devices(0))] #Returns playback devices
['Headphones (Oculus Virtual Audio Device)', 'MONITOR (2- NVIDIA High Definition Audio)', 'Speakers (High Definition Audio Device)', 'Speakers (NVIDIA RTX Voice)', 'CABLE Input (VB-Audio Virtual Cable)']
>>> mixer.quit() #Quit the mixer as it's initialized on your main playback device
>>> mixer.init(devicename='CABLE Input (VB-Audio Virtual Cable)') #Initialize it with the correct device
>>> mixer.music.load("Megalovania.mp3") #Load the mp3
>>> mixer.music.play() #Play it
To stop the music do: mixer.music.stop()
Also, the music doesn't play through your speakers, so you're going to have another python script or thread running that handles playing it through your speakers. (Also if you want it to play on a button press I recommend using the python library keyboard, the GitHub documentation is really good and you should be able to figure it out on your own.)
PS: This took me a while to figure out, your welcome.
PPS: I'm still trying to figure out a way to pipe your own mic through there as well since this method will obviously not pipe your real microphone in too, but looking into the source code of pygame is making my head hurt due to it all being written in C.
If you meant how to play MP3 using Python, well, this is a broad question.
Is it possible, without any dependencies, yes it is, but it is not worth it. Well, playing uncompressed audio is, but MP3, well, I'll explain below.
To play raw audio data from Python without installing pyaudio or pygame or similar, you first have to know the platform on which your script will be run.
Then implement a nice set of functions for choosing an audio device, setting up properties like sample rate, bit rate, mono/stereo..., feeding the stream to audio card and stopping the playback.
It is not hard, but to do it you have to use ctypes on Windows, PyObjC on Mac and Linux is special case as it supports many audio systems (probably use sockets to connect to PulseAudio or pipe to some process like aplay/paplay/mpeg123... or exploit gstreamer.).
But why go through all this just to avoid dependencies, when you have nice libraries out there with simple interfaces to access and use audio devices.
PyAudio is great one.
Well, that is your concern.
But, playing MP3 without external libraries, in real time, from pure Python, well, it's not exactly impossible, but it is very hard to achieve, and as far as I know nobody even tried doing it.
There is pure Python MP3 decoder implementation, but it is 10 times slower than necessary for real-time audio playback. It can be optimized for nearly full speed, but nobody is interested in doing so.
It has mostly educational value and it is used in cases where you do not need real-time speed.
This is what you should do:
Install pygame and use it to play MP3 directly
or:
Install PyAudio and some library that decodes Mp3, there are quite a few of them on pypi.python.org, and use it to decode the MP3 and feed the output to PyAudio.
There are some more possibilities, including pymedia, but I consider these the easiest solutions.
Okay, as we clarified what is really you need here is the answer.
I will leave first answer intact as you need that part too.
Now, you want to play audio to the recording stream, so that any application recording the audio input records the stuff that you are playing.
On Windows, this is called stereo mix and can be found in Volume Control, under audio input.
You choose stereo mix as your default input. Now, when you open an recording app which doesn't select itsown input channel, but uses the selected one (e.g. Skype) , it will record all coming out of your speakers and coming into your mic/line in.
I am not 100% sure whether this option will appear on all Windows or it is a feature of an audio card you have.
I am positive that Creative and Realtek audio cards supports it.
So, research this.
To select that option from Python, you have to connect to winmm.dll using ctypes and call the appropriate function. I do not know which one and with what arguments.
If this option is not present in volume control, there is nothing for it but to install a virtual audio card to do the loopback for you.
There might be such a software that comes packaged in as library so that you can use it from Python or whatever.
On Linux this should be easy using Pulseaudio. I do not know how, but I know that you can do it, redirect the streams etc. There is tutorial out there somewhere.
Then you can call that command from Python, to set to this and reset back to normal.
On Mac, well, I really have no idea, but it should be possible.
If you want your MP3 to be played only to the recording stream, and not on your speakers at all, well on Windows, you will not be able to do that without a loopback audio device.
On Linux, I am sure you will be able to do it, and on Mac it should be possible, but how is the Q.
I currently have no time to sniff around libraries etc. to provide you with some useful code, so you will have to do it yourself. But I hope my directions will help you.
Just an update on #PyPylia's answer for the benefit of anyone who struggled to implement this like I did.
Current Package Version: pygame 2.1.2 (SDL 2.0.18, Python 3.10.6)
Tested Systems: Windows 10 (21H2 - 19044.1288), (Should be the same process on Mac but this is untested as of now...)
First, you'll need to download the VB-Cable Virtual Mic Driver for your respective platform and install it. This provides us with a virtual mic that'll allow us to pass audio we play on our machine as a microphone input when using a video calling software (Google Meet, Microsoft Teams, Zoom). After that, it's all handled through the pygame module's audio package.
To get the audio device list:
from pygame import mixer, _sdl2 as devicer
mixer.init() # Initialize the mixer, this will allow the next command to work
# Returns playback devices, Boolean value determines whether they are Input or Output devices.
print("Inputs:", devicer.audio.get_audio_device_names(True))
print("Outputs:", devicer.audio.get_audio_device_names(False))
mixer.quit() # Quit the mixer as it's initialized on your main playback device
For example, My device returns:
Inputs: ['Microphone (High Definition Audio Device)', 'CABLE Output (VB-Audio Virtual Cable)']
Outputs: ['Speakers (High Definition Audio Device)', 'CABLE Input (VB-Audio Virtual Cable)']
Then, to playback the audio:
import time
from pygame import mixer
mixer.init(devicename = 'CABLE Input (VB-Audio Virtual Cable)') # Initialize it with the correct device
mixer.music.load("Toby Fox - Megalovania.mp3") # Load the mp3
mixer.music.play() # Play it
while mixer.music.get_busy(): # wait for music to finish playing
time.sleep(1)
If you wish to play multiple tracks back to back, add the following code segments to the while loop above:
...
else:
mixer.music.unload() # Unload the mp3 to free up system resources
mixer.music.load("Sleeping at Last - Saturn.wav") # Load the wav
...
Then, on the other end, inside the relevant software, just change the microphone input from the default to CABLE Output (VB-Audio Virtual Cable) to have those on the other end hear the audio from the source.
If you're using a newer version of the package and some of the listed methods don't seem to work because of an AttributeError: module 'pygame' has no attribute {method_name}, use pyup and search for the method in question, to see if there have been any changes to how the method is invoked. This was the main reason #PyPylia's code snippet no longer works unless you use an older version of pygame.
If you want to play an audio file in local directory, you may follow this flow.
#!/usr/bin/env python
import pyaudio
import socket
import sys
import os
CHUNK = 4096
output = os.path.join(BASE_DIR, "speech.wav") #WAV format Output file name
wf = wave.open(output, 'rb')
p = pyaudio.PyAudio()
stream = p.open(format=p.get_format_from_width(wf.getsampwidth()),
channels=wf.getnchannels(),
rate=wf.getframerate(),
output=True)
try:
while True:
data = wf.readframes(CHUNK)
stream.write(data)
except KeyboardInterrupt:
pass
print('Shutting down')
s.close()
stream.close()
audio.terminate()
I need to display the USB camera video of raspberry-pi in Wxpython with control buttons in it. I have managed to embed vlc in to Wxpython with control buttons (Got it from Google) to play existing video. Is there any way to stream the USB camera video in it?
Thanks in advance :)
If you've managed to embed VLC, you should just be able to point it at the v4l address for the webcam.
The v4l address should be along the lines of v4l:/dev/video0:size=640x480 (but it'll vary depending on your machine I guess). You may find it easier to use the standalone VLC client to get the address you need and then put it into your program.
This StackOverflow thread may be useful for later depending on what you're doing.
I have been working with some drones and robotics projects using arduino and python. There was a kickstarter project for a neat little hex copter, that hasn't been managed well.
I was lucky, i got my copter and then some time later after some frustrated email exchanges, i finally recieved the camera as well. To this day, their forum has people still complaining. Their maker forum is now down and their wiki hasn't been updated with any specifics on the camera.
http://www.flexbot.cc/wiki/index.php?title=Main_Page#Hardware
Their app to accompany the drone still doesn't support the camera module. Not that it'd matter, as their code isn't very well documented or annotated.
https://github.com/HexAirbot
There are some tips on switching the camera on the comments page of their kickstarter campaign.
https://www.kickstarter.com/projects/1387330585/hex-a-copter-that-anyone-can-fly/posts/1093716
So, sob story over, i'm stuck with this neat little wifi camera that i am unsure on how to connect to. I know how to switch it on and it does have a micro-usb port on it.
What library in Python could i use to stream an image from this camera given that it is a wifi camera. If i wanted the video stream as a numpy matrix.
I need to interface with the camera, so i can connect and disconnect.
Then, be able to read images frame by frame with ffmpeg. I have some python modules that can detect and read from a camera, but how can my code ensure that the camera is connected?
Totally stuck. Any help would be appreciated.
Considering you are building for the android platform, you will more than likely need to use some sort of java/python driver/interface, unless you just use java.
Here is an article on java/python, and using python from within java.
Using Python from within Java
We have a python program which outputs specific waveforms over the audio to drive an LED, for an easy and cheap robot programming device.
With the windows systems that we've tested everything works fine, but on some systems the waveform seems to be altered. We've used the control panel to disable any 'enhancements' for the audio output endpoint but it doesn't seem to help.
So, is it possible, using python, to instruct Windows to play audio unchanged? Or do some of the audio gurus here have another theory of what could be affecting the audio?
Sound cards are for playing audio, not sending data. You can't rely on an arbitrary signal not being altered by the hardware, much less the software. For example, many sound cards have a capacitor in series with the output to filter out DC bias. If you try to pass a DC-biased (or very low frequency) signal through such a sound card, it will be distorted. And there's nothing you can do about it at the software level.