Introduction

Switchboard Cellular Part 2 Audio was produced by Linguistic Data Consortium (LDC) catalog number LDC2004S07 and ISBN 1-58563-297-x.

The Switchboard Cellular Part 2 Audio collection focused primarily on cellular phone technology (all service types). The collection commenced 09/16/2000 and was completed by 12/15/2000. The project's goal was to target 200 subjects, balanced by gender, under varied environmental conditions to participate in (10+) five-six minute conversations on cellular phones. The speech data was collected for research, development, and evaluation of automatic systems for speech-to-text conversion, talker identification, language identification and speech signal detection purposes.

Data

This release contains speech data files only, along with documentation describing speaker information (sex, age, education, city and state where raised), call information (date, time, call duration, Personal Identification Numbers, topic), and audit information (channel quality, background noise). The documentation also contains reports on clipped files.

During the collection period, the LDC collected a total of 2,020 calls, or 4,040 sides (2,950 cellular, 2,405 female, 1,635 male), from 419 participants, under varied environmental conditions. There are a total of 2,020 speech files for a rough total of 202 hours of audio data (a little over 11 GB).

Each speech file consists of a 1,024-byte ASCII-formatted Sphere header, followed by two-channel interleaved mu-law sample data. The mu-law samples represent the actual digital data transmission from the telephone service provider (MCI), as captured separately for each side of the telephone conversation by the LDC's telephone collection platform. The header also indicates the caller_pin, callee_pin, topic_id, cellular service/handset information and speaker demographic information. The data files are not compressed.

Please examine this example audio file to review a sample of this corpus.

Updates

Content Copyright

Portions © 2004 Trustees of the University of Pennsylvania