audio

Rockbox audio format

How do you specify a callback for rb->pcm_play_data()? ...

Transcoding audio and video

What is the best way to transcode audio and video to show on the web? I need to do it programmatically. I'd like to do something like YouTube or Google Video where users can upload whatever format they want, and I encode it to flv, mp3, and/or mp4. I could do it on our server, but I would rather use an EC2 instance or even a web ser...

Accessing audio/video metadata with .NET

What is the best way to get and set the meta data for mp3, mp4, avi files etc. with .NET? ...

Detecting audio silence in WAV files using C#

I'm tasked with building a .NET client app to detect silence in a WAV files. Is this possible with the built-in Windows APIs? Or alternately, any good libraries out there to help with this? ...

What is a good free library for editing MP3s/FLACs?

What is a good free library for editing MP3s/FLACs. By editing I mean: Cutting audio file into multiple parts Joining multiple audio files together Increase playback speed of file without affecting the pitch (eg. podcasts up to 1.3x) Re-encoding audio file from Flac -> MP3 or vice versa I don't mean software, I mean a library that ...

How do I search content, within audio files/streams?

I have always wondered how many different search techniques existed, for searching text, for searching images and even for videos. However, I have never come across a solution that searched for content within audio files. For example: Let us assume that I have about 200 podcasts downloaded to my PC in the form of mp3, wav and ogg file...

Free Wavetable Synthesizer?

I need to implement a wavetable synthesizer in an ARM Cortex-M3 core. I'm looking for any code or tools to help me get started. I'm aware of this AVR implementation. I actually converted it to a PIC a while back. Now I am looking for something similar, but a little better sounding. ANSI C code would be great. Any code snippets (C or C+...

Must-see tech talks/presentations?

There are now several places that offer free audio or video tech talks/presentations online: I'm thinking of Google Tech Talks, IT Conversations, as well as some of the sites recommended in the answers to this question. So: are there any specific presentation(s) that you consider as "must-see", either in your area of interest or for all...

Can an audio object be embedded in an InfoPath form ?

Is it possible to embed an audio object (mp3, wma, whatever) in a web-enabled InfoPath form ? If it is, how do you do it ? ...

3.1 or 5.1 audio in Flash

Is it possible to do 3.1 or 5.1 audio using Flash? We're starting a project here for an interactive kiosk, and we've been told to use Flash. However, we also have a requirement to support either 3.1 or 5.1 audio (where 5.1 is the most wanted feature). I haven't done any high-tech audio stuff using Flash, so I was wondering if anyone...

What Are High-Pass and Low-Pass Filters?

Graphics and audio editing and processing software often contain functions called "High-Pass Filter" and "Low-Pass Filter". Exactly what do these do, and what are the algorithms for implementing them? ...

Change Active Sound Card on the Fly

I currently have speakers set up both in my office and in my living room, connected to my PC via two sound cards, and would like to switch the set of speakers I'm outputting to on the fly. Anyone know an application or a windows API call that I can use to change the default sound output device? It is currently a bit of a pain to travers...

Simple audio input API on a Mac?

I'd like to pull a stream of PCM samples from a Mac's line-in or built-in mic and do a little live analysis (the exact nature doesn't pertain to this question, but it could be an FFT every so often, or some basic statistics on the sample levels, or what have you). What's a good fit for this? Writing an AudioUnit that just passes the so...

Waveform Visualization in Ruby

I'm about to start a project that will record and edit audio files, and I'm looking for a good library (preferably Ruby, but will consider anything other than Java or .NET) for on-the-fly visualization of waveforms. Does anybody know where I should start my search? ...

How to do a sample rate conversion in Windows (and OSX)

I am about to write an audio file converter for my side job at the university. As part of this I would need sample rate conversion. However, my professor said that it would be pretty hard to write a sample rate converter that was both of good quality and fast. On my research on the subject, I found some functions in the OSX CoreAudio-fr...

Good python library for generating audio files?

Can anyone recommend a good library for generating an audio file, such as mp3, wav, or even midi, from python? I've seen recommendations for working with the id tags (song name, artist, etc) in mp3 files, but this is not my goal. Thank you very much! ...

Service to make an audio podcast from a video one?

Video podcast ??? Audio only mp3 player I'm looking for somewhere which will extract audio from video, but instead of a single file, for an on going video podcast. I would most like a website which would suck in the RSS and spit out an RSS (I'm thinking of something like Feedburner), though would settle for something on my own machin...

Algorithm to decide if digital audio data is clipping?

Is there an algorithm or some heuristic to decide whether digital audio data is clipping? ...

Creating MP4/M4A files with Chapter marks

I am trying to join together several audio files into one mp4/m4a file containing chapter metadata. I am currently using QTKit to do this but unfortunately when QTKit exports to m4a format the metadata is all stripped out (this has been confirmed as a bug by Apple) see sample code. I think this rules QTKit out for this job, but would be...

Slowing down the playback of an audio file without changing its pitch?

I am working on an application for college music majors. A feature i am considering is slowing down music playback without changing its pitch. I have seen this done in commercial software, but cannot find any libraries or open source apps that do anything like this. Are there libraries out there? How could this be done from scratch f...