audio-processing

I want to build something similar to Tunatic or Midomi (try them out if you're not sure what they do) and I'm wondering what algorithms I'd have to use; The idea I have about the workings of such applications is something like this: have a big database with several songs for each song in 1. reduce quality / bit-rate (to 64kbps for instance) and calculate the sound "hash" have the sound / excerpt of the music you want to identify for the song in 3. reduce quality / bit-rate (again to 64kbps) and calculate sound "hash" if 4. sound hash is in any of the 2. sound hashes return the matched music I

I just want to know if there is any build in libraries or external libraries in Java or C# that allow me to take an audio file and parse it and extract the text from it. I need to make an application to do so, but I don't know from where I can start. Here are some of your options: Microsoft Speech Lumenvox Dragon naturally speaking sphinx4 Here is a complete example using C# and System.Speech The code can be divided into 2 main parts: configuring the SpeechRecognitionEngine object (and its required elements) handling the SpeechRecognized and SpeechHypothesized events. Step 1: Configuring the

I want to compare 2 audio files programmatically. For example: I have a sound file in my iPhone app, and then I record another one. I want to check if the existing sound matches the recorded sound or not ( - similar to voice recognition). How can I accomplish this? That's called Audio Fingerprinting. There exist some open source projects from which you can get some ideas. Take a look here: Audio Fingerprint - MusicBrainz . Have a server doing audio fingerprinting computation that is not suitable for mobile device anyway. And then your mobile app uploads your files to the server and gets the

I'm looking for a library that simplify tempo/bpm audio detection. Something similar to this http://adionsoft.net/bpm/ , but to use on *NIX machines. Any language, but preference goes to php, perl, python. Mixxx uses the BPMDetect class from the SoundTouch library for BPM Detection. There is also another opensource library called BPMDj which is harder to use but is more accurate. I personally wouldn't rely on either though. Then again I am a hobbyist DJ so I tend to rely more on my ears. EDIT There is a much better OSS library called aubio . It can also do beat detection and onset detection.