Skills: none Concepts: introduction to and history of speech (with and without text) and music processing, audio file formats, the audio processing workflow, audio processing software and operations This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 License. Audio processing overview

Where does this topic fit? Internet concepts – Applications – Technology – Implications Internet skills – Application development – Content creation – User skills

When data types went mainstream Data typeDecade Numeric1950s Alphanumeric1960s Text1970s Image1990s Speech2000s Music2000s Video2000s HD video2010s

Music Speech Speech with text Let’s take a look at

Music research, 1950s

Napster,

Apple iTunes store, 2001

Music is moving to the cloud Will users shift to the cloud as technology improves?

Packet voice conference, January 1978 Watch the videoWatch the video (5m 18s)

Vocaltec Internet Phone, 1995

Skype, 2003

Speech synthesis demo Text to speech

Translation Microsoft research: Enabling Cross-Lingual Conversations in Real Time PR Demo of translation “breakthrough”

Complementary collaboration on machine translation since 1945 Government and industry investment are complementary

Audio processing work flow Capture Edit Compress Distribute

Speech recognition demo Speech to text

Audacity – the audio editor we will use Open source for: Linux Windows Mac

Popular audio formats WAV – usually uncompressed, large files MP3 – compressed, variable size files

Word processing operations Select text Cut text Copy text Move text Delete text Change fonts Change text size Change text color Change footnote style Check spelling Compress a text file Etc. etc. These are word processing operations. Can you think of some audio processing operations?

Word and audio processing operations Select text Cut text Copy text Move text Delete text Change fonts Change text size Change text color Change footnote style Check spelling Compress a text file Etc. etc. Select sound Cut sound Copy sound Move sound Increase/decrease volume Increase/decrease pitch Increase/decrease speed Fade in/out Combine multiple tracks Add echo Add reverberation Compress an audio file Etc. etc. Text dataAudio data

Before After How did I do this? Audio editing example

Audio utility programs Levelator Gizmo’s

Summary

Self-study questions We discussed three types of audio application – without looking back, what were they? We discussed two types of hybrid application involving both speech and text – what were they? If you listen to Internet music, do you download it or stream it? What are the pros and cons of downloading versus streaming music? Will future technology make downloading more or less attractive compared to streaming?

Resources Audacity audio recorder and editor: Audacity audio recorder and editor, portable version: Audacity "how to" videos: Neil Young on the need for higher quality music audio: and-what-you-can-do-about-it/