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Questions tagged [alsa]

ALSA stands for Advanced Linux Sound Architecture and is a kernel component that supports sound in Linux systems.

ALSA stands for Advanced Linux Sound Architecture and is a kernel component that supports sound in Linux systems. In the 2.6 version of the Linux kernel, ALSA replaced OSS (Open Sound System).

According to the project's website, ALSA does the following key features:

  • Efficient support for all types of audio interfaces, from consumer sound cards to professional multichannel audio interfaces.
  • Fully modularized sound drivers.
  • SMP and thread-safe design.
  • User space library (alsa-lib) to simplify application programming and provide higher level functionality.
  • Support for the older Open Sound System (OSS) API, providing binary compatibility for most OSS programs.

Independent ALSA and linux audio support site with info on audio hardware and drivers

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Python read output sound not input

Any clue on what the easiest way to read the system sound level is? I'm planning on creating an equalizer made out of short led strips and hooking them up to an Arduino or RaspberryPi. I've seen a lot of examples how to do it with the input, mic or…
PvdL
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A2DP sink without pulseaudio

So I'm trying to make my linux server play music sent from my Android phone using bluetooth (the linux machine is the A2DP sink and the phone is the source). What I have done so far is to: install bluez and enable audiosource/audiosink pair phone…
lode
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Need a simple example for audio recording

I am in need of simple audio recording and playing example using AudioRecorder in android. I tried with MediaRecorder, it works fine.
Manikandan
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raspberry pi / aplay / default sound card

I purchased a the "Sound Blaster Play! 2" soundcard for my raspberry pi 3. The OS is raspbian jessie. The audio on my raspberry pi works when I run $ aplay /usr/share/sounds/alsa/Front_Center.wav -D sysdefault:CARD=S2 But only when I use -D. When…
Franky
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Is audio playback via ALSA supported in Qt5?

I have a small C++ Qt program that uses a QAudioOutput instance to emit sound. It compiles & runs fine using Qt 4.8.5. However, in Qt 5.0, 5.1, and 5.2, my application compiles, but does not work. I get the following error message while the…
reddish
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ALSA: open a PCM device in shared mode

I want to playback some audio data using ALSA to a PCM device. As an example I have downloaded this sample example and run it in my PC. It works fine when no other process is currently using the sound card. But it doesn't play anything when some…
MD Sayem Ahmed
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Watch for volume changes in ALSA/Pulseaudio

How do you listen to changes in volume on the Master channel on the default sound card? I'd like to be notified through dbus or a callback or something that the volume has changed. I have tried looking and the ALSA and PulseAudio APIs and they only…
Michael Eden
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Trying to record from microphone and playback in real time

I'm trying to record data from my microphone and then play it back through the speakers in real time, and with some delays, but I'm having some problems with it. I chose to use python and alsaaudio, and my current script I'm having problems with can…
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Audio Recording in Python

I want to record short audio clips from a USB microphone in Python. I have tried pyaudio, which seemed to fail communicating with ALSA, and alsaaudio, the code example of which produces an unreadable files. So my question: What is the easiest way to…
jsj
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ALSA: How to tell when a sound is finished playing

I have a c++ object that accepts sound requests and plays them with ALSA. There is thread that processes the sound requests. Some sounds are periodic and are rescheduled after the wav file contents have been written to the ALSA library. Is there a…
waffleman
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ALSA buffer xrun induced by low quality source in ffmpeg capture

I am attempting to transfer some old Video 8 tapes to my computer, though an EasyCap USB stick and the motherboard's sound line-in, on Ubuntu. I believe the arguments are correctly laid out below to capture from two independent streams, and encode…
Peter Becich
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ALSA application to read and play a WAV file on Raspberry Pi

Trying to learn the ALSA audio layers to eventually write an ALSA device driver for the Raspberry Pi platform. Starting simple, I glued together various samples from the ALSA project site and other online sources to do the simplest thing: read a WAV…
Mark McMillan
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ALSA snd_pcm_drop() is not clearing complete buffer

I am using ALSA API snd_pcm_drop() to clear the buffers. But when I continue audio later with snd_pcm_prepare(), I can hear part of previous audio which was supposed to be cleared. This happens when I have a high value of…
Lunar Mushrooms
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Android emulator sound - ubuntu

Using Ubuntu 10.04 64 bits for Android development and everything goes well except sound. I've using -audio option and -audio-out one with alsa as backend parameter, but without luck. ¿Any idea?
Juanin
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Implement realtime signal processing in Python - how to capture audio continuously?

I'm planning to implement a "DSP-like" signal processor in Python. It should capture small fragments of audio via ALSA, process them, then play them back via ALSA. To get things started, I wrote the following (very simple) code. import…
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