iPhone aurioTouch example: Remove DC
I am looking at the iPhone aurioTouch example specifically on the following code: static OSStatus PerformThru( void *inRefCon, AudioUnitRenderActionFlags *ioActionFlags, const AudioTimeStamp *inTimeStamp, UIn...
audio
WPF Storyboard delay in playing wma files
I'm a complete beginner in WPF and have an app that uses StoryBoard to play a sound. public void PlaySound() { MediaElement m = (MediaElement)audio.FindName("MySound.wma"); m.IsMuted = false; FrameworkElement audioKey = (FrameworkElement)keys.FindName("MySound"); Storyboard s = (Storyboard)audioKey.FindResource("MySound.wma"); s.Be...
dynamically (un)link elements in a running (gstreamer) pipeline?
there are plenty of examples in the gstreamer documentation on constructing and running static pipelines. however, there isn't much about changing/relinking elements in a live pipeline - while the media is actually flowing. it's definitely possible, so the question is: what gstreamer concepts/mechanics should i understand before attemp...
iPhone Remote Audio Unit callback
I am looking at Audio Unit Development Fundamentals. Assuming UInt32 sessionCategory = kAudioSessionCategory_PlayAndRecord; status = AudioSessionSetProperty( kAudioSessionProperty_AudioCategory, sizeof(sessionCategory), &sessionCategory); with sample rate 44,1000 and allocate the buffer large...
What library I need to use for setting Windows mixer volume control in c#?
Hi, I want to make program which is detecting any microphone activity from specified level. If there is any activity it set Windows master volume to specified level. When someone will stop talking it must restore previous volume in few seconds. What library I need to use? (it must work under Windows XP, Vista, 7). Thank you for your repl...
Audio using Yeti Mic does not work on iPhone Simulator
I am following iPhone Core Audio Tutorial by Tim Bolstad. It works as expected. I can hear the audio successfully. But when I plug-in USB Yeti Stereo Microphone by BlueMic on my MacMini. It does not produce the sound anymore. Why is that? Thanks in advance for your help. ...
How to get the frequency spectrum of a segment of samples from a AudioInputStream?
Is there a nice (pure Java) open source libary to get the frequence spectrum of samples taken from a AudioInputStream? ...
Joining mp3 files without delay at the end of each piece
I am writing a program which needs to join some guitar chords (in mp3 format), but without having that end of sound feeling for each part of it.. Using cat or mp3wrap still gives that kind of feeling... Basically I don't know how to come up with the idea. For example, should i open each file as stream and delete some bytes at the end, t...
Low pass filter using FFT instead of convolution implementation
Implementing a low pass FIR filter, when should one use FFT and IFFT instead of time-domain convolution? The goal is to achieve the lowest CPU time required for real-time calculations. As I know, FFT has about O(n log n) complexity, but convolution in the time domain is of O(n²) complexity. To implement a low pass filter in the frequen...
Loading Multiple Audio files from SD card...
I need help/pointer to doc/sample code on how to load multiple audio files from a specific folder on the SD card and have it play a random file back(i think i can figure out the last step if i could just figure out how to load multiple files). Here is my incredibly poorly written app so far, don't judge too harshly as I'm learning as I ...
How to extract audio/video file duration?
I need to find the duration of numerous formats of audio and video files, in milliseconds. I've been searching around for a while, but I can't find anything that will let me do this. I'm using C/++ in Linux. Thanks in advance. ...
Best backwards compatible way to programmatically capture sound going to speakers
What would be the best approach to take in order to achieve a backwards compatible (Windows XP through Windows 7) way to capture sound that is being sent to the speakers on a machine, even if the audio driver doesn't expose the "Stereo Mix" recording device. For extra points, it would be great if this approach allowed for capturing soun...
play wav files one after the other in java
I'm trying to play a few WAV files after each other. I tried this method: for (String file : audioFiles) { new AePlayWave(file).start(); } but that plays them all at the same time. So i need a function that looks like this: public void play(Vector<String> audioFiles); the vector contains the files, eg: "test1.wav","test2.wav" ...
How to use Alvas.Audio to detect any sounds?
I have a problem with start to code my app. How I can detect sounds provided to my microphone using Alvas.Audio library? Could anyone provide me a sample code (i don't know how to use bulit-in function in that library)? ...
Setting volume on Audio Unit (kAudioUnitSubType_RemoteIO)
How to set volume on Audio Unit specifically on kAudioUnitSubType_RemoteIO ? I saw something for kAudioUnitSubType_MultiChannelMixer status = AudioUnitSetParameter(mixerUnit, kMultiChannelMixerParam_Volume, kAudioUnitScope_Output, AU_OUTPUT_BUS, volume, 0); Thanks in advance for your help ...
Input from 20+ microphones
I've been asked (if it's possible) to write a program monitoring the input of at least 20 microphones, on a single computer. Currently I'm prototyping in python (2.6), on a Ubuntu system using Alsa. My attempts so far have created quite a few questions... Ubuntu is a requirement, Alsa isn't, and python is an ideal. For hardware, one s...
Audio programming, Sound Processing and DSP
I was playing with a karaoke application on iPhone and came up with following questions: The application allowed its users to control the volume of the artist; even mute it. How is this possible? Does adjusting artist sound/setting equalizer etc. mean performing some transformation of required frequencies? What sort of mathematics is r...
what audio formats are supported by the android browser?
What audio formats can be played using the html5 'audio' tag in the android browser? Does anyone know where to find official specs on what the android browser supports and not? For the record, the android media formats page does not seem to cover this - I have soundfiles (3gp) playing fine in a native app, but they won't play in my weba...
AudioFileWriteBytes returns error -50 randomly
I have the following code snippet: OSStatus status = AudioFileWriteBytes(self.audioFile, FALSE, self.startingByte, &ioNumBytes, theData); The status code randomly returns noErr and -50 on the iPhone simulator. It then works if I re-run it. Any pointer is appreciated why the above code behaves randomly. Thanks in advance for you...
Generate a waveform image from an audio file
Building a python application that converts raw audio files into wave using sox on a linux system. I want it to be able to generate an image (PNG or Jpeg) of the audio waveform pattern but I am unable to find a command line tool or python package that will do this. Not being an experience Python programmer my options are limited. There ...