Music streaming and downloading: an introduction

Richard Ranft

The British Library Sound Archive

IAML Annual Study Weekend – April 2006

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Principles: file sizes,

audiences, copyrights

Audio file types

Preparing sound files

Delivery methods

Examples

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Digital audio

“Music is a time-frequency wave function with tonal qualities pleasing to the human ear” – ALICE

Digital audio files are large… In a simple text file (Windows Notepad), one character or

space requires 1 byte storage The 325 letters and spaces on this page occupies 325

bytes This same text as recorded speech = 1,000 x larger

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File sizes & data rates

8 bits = I byte

Data storage sizes measured in bytes CD 650 MB 1 minute @ CD quality ~ 10MBytes Typical desktop computer hard drive 60 GBytes

Data transfer rates measured in bits per second

CD quality stereo 1,411 kbit/s

Modem connection up to 56 kbit/s

Broadband connection from 256 kbit/s

LAN from 10 Mbit/s

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A quart into a pint pot

Downloading Playback cannot start until entire file received by user Playback is continuous (no buffering) Transfer high quality, uncompressed files

Compression Lossless compression, e.g. MLP, FLAC, 50% reduction Lossy compression (“data reduction”), e.g. mp3, AAC, RealAudio, >80%

reduction Used for streaming media

Streaming Fast delivery, but lower quality than downloading Useful for previewing Instant playback: plays when you click Can use to discourage copying Buffering: used to control network interruptions Live streaming used in ‘broadcasting’ radio shows

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Your audience

Why deliver sound?

Who are your audiences?

What content do want to deliver?

How to deliver content?

Accessing the content

Rights issues

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File types

Uncompressed files WAV AIFF 3-minute song (32 MB): several hours to download over modem

Compressed files MPEG-1 layer III .mp3 (typically 10:1 compression at 128 kbps) Ogg Vorbis .ogg Quicktime Windows Media Audio .wma Choice of bitrates

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Preparing files

Master files v. access files

Digitisation & editing Use high quality files during preparation Edit with e.g. Wavelab (Steinberg), Adobe Audition (Adobe),

SoundForge (Sony), Audacity (freeware)

Conversion from WAV to access version file Batch conversion tools Batch renaming e.g. Rename4u

Upload to server

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Delivery

Simple web page

Choice of file types and qualities

Streaming & streaming servers

Podcasts

Preventing piracy:

Use short samples or low resolution

Watermarking, encryption, streaming

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www.arkive.org

3 file types offerred (with video), each at 2 bitrates

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Click to add title

Cylinder Preservation & Digitization Project: http://cylinders.library.ucsb.edu

3 file types offerred: Quicktime for streaming; mp3 and wav for downloads

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Examples

British Library Sound Archive

5 million recordings: musical works, interviews, recordings of plays and poetry, wildlife sounds, oral history, sound effects

580,000 hours (excluding second copies)

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66 years non-stop listening 6 years added per year

Most of the recordings are

in copyright

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Access

Access: CD publications,

exhibitions & talks, radio

broadcasts, copying service;

listening services

- where rights can be cleared,

or where BL owns rights

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Listening access in three arenas:

Off site, all web users, via BL website Collect Britain (1,400 sounds), plus 800

other sounds, where copyright permissions have been granted or are in public domain (older than 70 years).

Off site, selected web users, to FE & HE communities in the UK Archival Sound Recordings Project:

12,000 sounds by September 2006.

On-site access unrestricted (3 million sounds…)

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www access to British Library sounds

Before 2006: RealAudio streaming format RealServer Surestream

Now: WMA streaming using MMS Windows 2000 server software 45 simultaneous users, but can accommodate many more 400 GB server storage capacity

Downloads not yet available Mp3 downloads of Archival Sound Recordings Project

recordings from September 2006

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www.bl.uk/nsa

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On-site access

For IPR reasons, continuing requirement to provide on-site access

Manual Listening & Viewing Service, appointments-based

Many recordings too fragile to be handled by listeners

Headphone listening in soundproof study carrels

Limited number of carrels Cannot meet increasing demand from

playwrights, media researchers, oral historians, musicologists, etc

Risk of handling damage

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SoundServer

A new service, providing instant

access to many sounds in selected

Reading Rooms

Access to digital surrogates of

recordings stored on webserver

‘Point & Click’ delivery from self-

service workstations in reading rooms

Use of ‘leak-proof’ self-muting

headphones on selected Reading

Room terminals

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How does SoundServer work?

Staff receive request for CD listening

On-demand encoding to mp3 files

Files transferred to Windows 2003 server

Personal playlist created by staff using a web form

Playlist links to mp3s and to Sound Archive catalogue

Listeners wait 5 working days for pre-ordered custom playlists

Listener accesses their personal list via Reader number

Sounds relayed over 100 Mbps network to Media Player Classic

player on web browser

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SoundServer: benefits

Removes need for appointments

Semi-automated service - listener-controlled playback

Potentially many simultaneous users

Increasing on-line data bank of audio

Reduced wear on collection items

Entire SoundServer collection accessible to any visitor via

‘Jukebox’ pages

Runs in parallel with existing appointments service, using

existing staff resources

Low cost: capital costs of £14k for server store, headphones &

2 workstations, but rest of service uses existing simple, low-

cost technology, & existing staff

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SoundServer: disadvantages

Lower sound quality of surrogates – but acceptable to most users

Highly dependent on IT infrastructure/reliable network to add and access content

Users wishing to read sleeve notes and view artwork must still make an appointment – but audio-only access acceptable

Need to continue existing appointments-based manual service in parallel for ‘difficult’ audio formats and for sleeve notes and video viewing.

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Progress so far

Nine PC terminals

Currently limited to CD

recordings

A growing collection - now

3,000 recordings -

accessible by any readers

browsing the Jukebox

- including our most

frequently requested items

Feedback from listeners is

very positive

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SoundServer developments

Extra SoundServer terminals in reading rooms and in public areas of building

100,000 files in 4 years

Adding e.g. BL CD publications: ‘try before you buy’

Integration with other electronic audio resources, other BL electronic resources (e.g. Oral History transcripts, Naxos on-line library)

Introduce improved playback facilities (bookmarking, saved searches)

Submitting playlist requests via a webform

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Growth in listening and viewing use

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60

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100

120

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07/08/05 07/10/05 07/12/05 07/02/06 07/04/06

date

nu

mb

er/

we

ek L&V appointments-

excluding SoundServer

Weekly L&V (inc. SS)totals

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Click to add title

Thanks for listening.

Questions?